Automation, Technology Focus on Savings
France WMA Ups Tech Use Save Money: Plan Your Move Make High RAP Work Maintain Your Dratch Plant P&D, NEA Take Systems Further Learn Technology Upgrades Before WOA february 2012
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Departments Letter from the Editor 5 Sharing Good IARC News Takes PR Talent
contents
Around the Globe 6 Safety Spotlight 8 Save $11,000 per Text Engineers at inthinc help you protect workers, bottom line with cell-use detection by Sandy Lender Mix It Up 10 MGRF Replaces RTFOT by AsphaltPro Staff 10 Jury is In: Use HMA to Design WMA by AsphaltPro Staff Equipment Maintenance 12 Here’s How to Adjust Dryer Flights Young offers optimum efficiency advice before and during WOA by AsphaltPro Staff 20 Batch, Dratch Winter Checklist by Cliff Mansfield Producer Profile 26 Blend, Report, Improve Construction Resources Management finds more ways to automate quality for P&D, NEA by Sandy Lender
Articles 24 Get NCAT Info First-Hand by Buzz Powell
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30 Determine Dynamic Modulus, Flow Number with AMPT by NCAT Researchers 34 Here’s How to Quality Control Your High RAP by AsphaltPro Staff 38 Ermont Applies Evotherm® WMA French motorway serves as positive testing ground for warm-mix performance by Frédéric Delfosse
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42 Pennsylvania’s McCormick Hosts Senator by AsphaltPro Staff 42 Brown Accepts New NCAT Hat by AsphaltPro Staff
Equipment Gallery 66 Get in the Zone by Jennifer McNally
44 Plan For Plant Moving Costs by Sandy Lender
Here’s How It Works 70 Diamond Key’s Bitumen Loading Module
48 Preview Asphalt, Aggregate Advances of the World by Sandy Lender
72 Gilson’s SG-4 Last Cut 74 Non-OPEC Outlook Forecasts Growth by the Energy Information Administration
56 International Precision Work by AsphaltPro Staff
Resource Directory 73
58 Palm Beach Floats Aggregate Production by Carl Emigh
Automation, Technology Focus on Savings
France WMA Ups Tech Use Save Money: Plan Your Move Make High RAP Work Maintain Your Dratch Plant P&D, NEA Take Systems Further Learn Technology Upgrades Before WOA FEBRUARY 2012
65 Wooten Wins Top Honor by AsphaltPro Staff
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On The Cover…Warm-mix asphalt additives bring temperatures down around the globe with energy saving results everyone wants to see. See related article on page 38. Photo courtesy of MeadWestvaco. www.theasphaltpro.com | ASPHALT PRO 3
February 2012 • Vol. 5 No. 5
2001 Corporate Place Columbia, MO 65202 573-499-1830 • 573-499-1831 www.theasphaltpro.com publisher
Chris Harrison associate publisher
Sally Shoemaker sally@theasphaltpro.com (573) 499-1830 x1008 editor
Sandy Lender sandy@theasphaltpro.com (239) 272-8613 Art Director
Kristin Branscom operations/circulation manager
Cindy Sheridan business manager
Renea Sapp AsphaltPro is published nine times per year: January, February, March, April/May, June/July, August/September, October, November and December by The Business Times Company, 2001 Corporate Place, Columbia, MO 65202 Writers expressing views in AsphaltPro Magazine or on the AsphaltPro website are professionals with sound, professional advice. Views expressed herein are not necessarily the same as the views of AsphaltPro or Business Times Company staff, thus producers/contractors are still encouraged to use best practices when implementing new advice. Subscription Policy: Individual subscriptions are available without charge in the United Sates, Canada and Mexico to qualified individuals. One year subscription to non-qualifying Individuals: United States $90, Canada and Mexico $125.00 and $175.00 all other countries (payable in U.S. funds, drawn on U.S. bank). Single copies available $17 each.
editor's note
Sharing Good IARC News Takes Minimal PR Talent
Not many folks know that one of the hats I’ve worn in recent years was that of public relations liaison at a university. I entertained the idea of getting my Accreditation in Public Relations (APR) until a book publisher gave me a contract for my first fiction novel. I chose to pursue the writing dream instead. During my month of prep for the APR, I crammed a ton of PR info into my brain. At the 57th annual NAPA meeting in Palm Desert, Calif., Jan. 24, that information came rushing back during general session III. That session discussed how to communicate the International Agency for Research on Cancer (IARC) findings to your community.
The Monograph You Know
You have read in this publication and on our social media platforms that IARC issued a statement in November assigning occupational exposures to straight-run asphalt cement (AC) and its emissions during road paving to the Group 2B classification. That means it’s “possibly carcinogenic” to humans—just like talc body powder. In discussions with people who have a vested interest in promoting lower temps for asphalt production, I heard some pessimistic talk about Group 2B. I decided it was time to share the general session PR info with all of you. The classification our industry enjoys is based on practices in place a decade ago. We were a cautious industry then. We made equipment modifications that directed fume away from workers—just in case. We made fume, emission and dust removal systems at the plant to keep our air clean as a whistle. Look at how much more environmentally friendly we’ve become. As the salespeople I mentioned above have missed, we’re dealing with lower temperatures for asphalt production most of the time, which means even less fume and emission than those the IARC scientists worked with. Group 2B has a couple obnoxious members, like the Titanium dioxide that the PCA wants to put in concrete, but it also has items that researchers have turned the tables on. CNN Health reported May 18, 2011, on Health.com that coffee, a Group 2B member, is linked to lowering men’s “risk of fatal prostate cancer.” The same article reported: “Coffee consumption has been linked to a lower risk of type 2 diabetes…” and so on. I’m not suggesting we run out and drink six cups of coffee a day, just as I’m sure we won’t run out and remove the exhaust pipes on our pavers. Common sense is still a factor in overall health, but it’s nice to know IARC has proved our industry safe on the fume front.
How To Share It
I don’t mean to rehash information you’ve already heard. I wish to give you points you can share with your co-workers. As speaker Dr. Vincent Covello of the Center for Risk Communication told the audience at the annual meeting, “People want to know that you care before they care what you know.” That means you want to get down to the basics of PR when you talk to them. You want to speak with compassion, conviction and optimism. Covello called this “CCO.” We can call it “relating to people.” Simplify your message. I’ve given you a lot of information about the IARC result in this note and you can get more at www.asphaltpavement.org, but you don’t want to regurgitate facts when someone asks you about a perceived danger of asphalt continued on page 9 www.theasphaltpro.com | ASPHALT PRO 5
around the globe
Industry News and Happenings from Around the World China
Shanghai Pudong Road & Bridge Construction Co., Ltd., reported Jan. 17 that the company would issue up to U.S. $316.63 million in new shares to finance building roads that service the Shanghai Disney Resort. That comes to 160 million or fewer new shares priced at least 7.22 yuan per share. According to a repurchase agreement, the district government of Pudong New Area has agreed to buy the roads from the company once they’re completed. Source: Reuters
Indonesia
As Southeast Asia’s biggest crude oil producer, Indonesia will boost investment in refineries further with the construction of a $1.4 billion fuel-processing unit in Central Java. The country’s state oil company, PT Pertamina started construction on the residual fluidized catalytic cracker in December 2011 at its Cilacap refinery and anticipates it will start operations in the third quarter of 2014 with a daily capacity of 62,000 bbl. Source: Bloomberg
Spain
Argus Media’s Europe/Africa Bitumen Conference takes place in Barcelona, Spain, May 16 through 17, 2012. Visit http://www.argusasphalt. com/index.html.
United States
For updates, opinion and links concerning funding legislation, fast news, quick contest deadlines, etc., be sure to check the website at www. theasphaltpro.com, our facebook page or our twitter account at http://twitter.com/AsphaltPro. We’d love to connect more often!
Appalachian Basin
The trio of Chesapeake Energy, American Electric Power Co. and Spectra Energy Corp. will expand shipping capacity by 18 percent, with 70 miles of new lines, on the Texas Eastern Pipeline system to handle the natural gas production from the Utica and Marcellus shale formations. They expect the new pipelines to be operational by November 2014 and expect the additional distribution to expand demand for natural gas from shale deposits. Source: Forbes.com
California
The California Department of Transportation (CalTrans) has accepted the use of the Astec Industries’ warm-mix system for use on any CalTrans project. At press time, the Astec warm-mix 6 February 2012
system was the only water-foaming technology for producing WMA approved by CalTrans.
Colorado
By the end of 2011, five more entities had given Atlas Copco, Commerce City, Colo, a nod of global approval. Newsweek, Thomas Reuters, Forbes, the Patent Board of global industrial equipment manufacturers and the Dow Jones Sustainability World Index for 2011 recognized the industrial group for its environmental strides and innovations.
Georgia
C.W. Matthews Contracting Co., Inc., Marietta, Ga., won the $7.7 million Bartow County road widening contract in Georgia. It’s one of more than $35 million in statewide road and bridge improvement contracts the Georgia DOT approved at the end of 2011 and it will require Matthews to widen and reconstruct 1.729 miles of truck passing lanes of SR 20 from Timberlake Cove Road to Bells Ferry Road. Reames and Son Construction Co., Inc., Valdosta, will take on resurfacing 13 miles of SR 38 in Lowndes County for $5.3 million. Oxford Construction Co., Albany, will resurface 13 miles of SR 45 Alternate in Calhoun and Clay Counties for $3.4 million. Also, Littlefield Construction Co., Waycross, will resurface 21.5 miles of SR 17 in Jenkins and Screven Counties for $2.3 million. Source: RomeNews-Tribune.com
New York
Gov. Andrew Cuomo proposed Jan. 4 in his state of the state address a $15 billion plan to repair roads, bridges, parks, flood control and municipal water systems under one umbrella “New York Works” fund. He proposed the idea of one entity making funding decisions so the state can repair 2,000 miles of roads, finance upgrades to 90 municipal water systems, improve 48 parks and historic sites, and repair 114 flood control projects. Source: TransportationNation.org
North Carolina
• S.T. Wooten Corp., Wilson, N.C., has won some NCDOT projects for 2012. Their crews will mill and resurface both directions of U.S. 301 southwest of Wilson, from Lely Rd. through Lucama to Aycocks Crossing Rd. for a $1 million contract. Their crews will also resurface several sections of U.S. 301, U.S. 70 Business, N.C. 96, N.C. 210 and U.S. 701 in Johnston County totaling 16.3 miles for a $2.2 million contract. These are just two of 30
contracts totaling $82.6 million that Secretary Gene Conti awarded in January for highway and bridge projects across North Carolina. The contracts came in about $7.2 million below NCDOT expectations. • Prepare for the industry’s largest asphalt offering at the World of Asphalt. The conference and exposition will be held March 13 through 15, 2012, in Charlotte, N.C. Visit http://www. worldofasphalt.com/ for reservations and the conference schedule.
Oklahoma
Terex has streamlined its North American Roadbuilding manufacturing facilities, putting General Manager Don Anderson at the helm. David Rinas will lead the team of salespeople who each offer the entire Terex Roadbuilding equipment lines. You can contact Rinas at david.rinas@terex.com.
Pennsylvania
• Eriez®, Erie, Pa., celebrates its 70th anniversary this year with a number of goals planned, including opening new or upgraded plants in Canada, China, India and the United Kingdom. • Volvo Construction Equipment, Chambersburg, Pa., gives contractors the chance to win attendance to its Road Institute® and other cool items like free VIP tickets to the May 27 stock car race in Charlotte, N.C. To enter, visit facebook.com/volvocena or visit the Volvo booth #1205 during World of Asphalt or visit volvoce.com/sweeps. Good luck!
Tennessee
• Jason Clark moves from parts manager for the Dillman division of Astec to Astec regional parts sales manager for New England. As such, he’ll have access to OEM plant parts for Astec, Barber-Greene®, McCarter, Esstee, Dillman and more. Reach him at (423) 8674210. * The 18th annual C&D World, which is the annual meeting of the Construction Materials Recycling Association (CMRA), will be March 25 through 27, 2012, at the Nashville Convention Center. Visit www.cdrecycling.org for more information or contact mbohan@miningmedia.com.
Utah
The Utah Asphalt Pavement Association (UAPA) is on its way. The association’s first executive director, Reed Ryan, took office Jan. 8. You can follow the group on Twitter at UtahAsphalt.
safety spotlight
Save $11,000 per Text
Engineers at inthinc help you protect workers, bottom line with cell-use detection by Sandy Lender
C
ommercial drivers can no longer legally use a hand-held mobile telephone while operating a commercial vehicle, according to a Nov. 23, 2011, press release from the U.S. Department of Transportation. The joint rule from the Federal Motor Carrier Safety Administration (FMCSA) and the Pipeline and Hazardous Materials Safety Administration (PHMSA) is intended to
From now on, commercial truck drivers cannot legally send text messages or make cellular phone calls while their vehicles are moving. That makes a safer environment for drivers, the general public, site workers, work zone members and others. It also means greater liability for company owners when drivers don’t follow the rules.
Prevent safety hazards and fines that could take fully trained drivers out of your employ with the cell and text detection antenna from inthinc Technology Solutions, Salt Lake City. 8 February 2012
end distracted driving. According to the U.S. DOT press release, approximately 4 million commercial drivers will be affected by this final rule. Under this rule, drivers who violate the restriction will face federal civil penalties of up to $2,750 for each offense. Drivers can be disqualified from operating a commercial motor vehicle if they rack up multiple offenses. If a commercial driver has two or more serious traffic violations, states will suspend the driver’s commercial driver’s license (CDL). Commercial truck companies that allow their drivers to use hand-held cell phones while driving will face a maximum penalty of $11,000. How can an owner or general contractor keep fines and liability from stacking up given this new rule? A written addendum in the company’s safety program makes a nice start, but won’t hold up in an investigation. The preventive is the cure. “The Department of Transportation has made it clear that the responsibility rests with the carriers and that written anti-cell use policies are not sufficient preventive measures,” Todd W. Follmer said. He’s the CEO of inthinc Technology Solutions, Salt Lake City, which is a global company centered on telematics, fleet solutions and driving safety. “Distracted driving accounts for 16 percent of traffic fatalities; our cell detection service provides the only reliable detection technology in the market, allowing managers to be notified when a cell phone is being used and take appropriate action.” Dec. 15, 2011, the company announced the availability of the cell and text detection antenna to be added onto inthinc’s driver safety and fleet management solutions. The antenna detects cell phone wave frequencies emitted from the driver seat, verbally warns the user to ter-
minate the call or text, and sends real-time alerts to a web portal or directly to a manager. This information allows fleet managers to enforce compliance with company, state and federal regulations, including the standards set forth in recent National Transportation Safety Board (NTSB) recommendation—reducing distracted driving, costly fines and crashes associated with this dangerous behavior. The company worked closely with federal entities to design the cell and text detector according to specs recommended by the FMCSA, NTSB, National Highway Traffic Safety Administration (NHTSA) and the DOT. They created a system that integrates with inthinc’s current fleet management and driver safety solutions, waySmart™ and tiwiPro™. The new product detects cell phone waves emitted from the driver seat, warns drivers and passengers to terminate the use, and reports it to the inthinc.com management portal or directly to a manager. This technology is designed to decipher various wave frequencies including phone calls, text messages and emails. Managers may adjust the settings to either send an in-cab voice alert to drivers when a cell signal is detected, or report the violation to the manager via e-mail or text alert. Customers can also get softwarebased smartphone apps as signalblocking preventive measures, but there may be limitations based on smart phone technology. The cell detection antenna is now available for order. Current inthinc customers can upgrade their vehicles with a 20-minute installation. Call (866) 294-8637 for more information, or e-mail contact@inthinc. com or visit http://www.inthinc.com. Tell them you saw it in AsphaltPro Magazine.
continued from page 5
fume. You want to assuage his fears with a short, compassionate message. Covello called this the 27/9/3 approach. This is an options approach. You either give an answer that is 27 words long or 9 seconds long or that contains 3 messages. Personally, I would stay away from the three-message concept when dealing with people who are emotionally involved in an issue. When a person gets “emotional,” Covello said the person’s ability to understand language drops about four grade levels. Considering our society’s “ability” starts at about an 8th or 10th grade level, you have a low vocabulary to work with. One place to start is with the free, downloadable PowerPoint presentation, “IARC Monographs: Occupational Exposures to Bitumens & Their Emissions,” that resides on the NAPA website. It explains how to share the results of the IARC monograph with your employees starting with definitions to get everyone on the same page. It has editable templates; you can alter each slide to your needs. Don’t need a “types of science” slide? Delete it. During the talk at the NAPA meeting, Michael Mangum of Mangum Asphalt Services suggested that any discussion of the IARC study should be a conversation with workers and not a presentation to or at the workers. Let them feel open to asking questions.
Anything Else?
At this time, the IARC committee members are working on a written document regarding the asphalt fume monograph. Their goal, Mangum said, is to have it published by the end of 2012. NAPA’s Executive Director Mike Acott said, “We don’t expect any further IARC activity for 25 years.” Mangum agreed that research will be within our own ranks. “Good research will continue because NAPA and industry are committed to keeping workers healthy and safe.” Now that’s a great message for any of us to share. Stay Safe
Sandy Lender
“Please consider the importance of having a conversation about the results with your co-workers.” —Michael Mangum www.theasphaltpro.com | ASPHALT PRO 9
mix it up
MGRF Replaces RTFOT by AsphaltPro Staff
U
nder the auspices of the National Center for Highway Research Program (NCHRP), Project 9-36 was designed to help researchers find ways to improve asphalt binder aging technologies. Project leaders chose the Stirred Air Flow Test (SAFT) and Modified German Rotating Flask (MGRF) methods as fairly inexpensive ways to test both neat and modified binders. Both methods are considered easy to do and able to reproduce aging results similar to those of the Rolling Thin Film Oven Test (RTFOT). Unfortunately, neither seemed to give great results for long-term aging of binders at the outset, and that’s what the researchers wanted to get at. They ended up selecting the SAFT method to try getting aging results similar to those of the pressure aging vessel (PAV) under AASHTO R28 for long-term aging. That meant adding a volatile collection system (VCS) study to quantify the volatility of binders tested in the SAFT and adding an optimization study to get the operating parameters for the SAFT. The goal was to make the SAFT reproduce the level of aging neat binders experienced with the RTFOT. At the end of the project, researchers performed a verification study to compare the properties of binders aged in both the SAFT and MGRF with the binders aged in the RTFOT according to the AASHTO R30 testing procedure. The results from the verification study gave researchers the information they needed to make recommendations from the NCHRP Project 9-36. “Based on the findings…the MGRF is considered an acceptable replacement for the RTFOT. For neat binders,
MGRF and RTFOT conditioning produced similar rheological properties. MGRF and RTFOT conditioning also produced similar rheological properties for typical polymer-modified binders….Another consideration in NCHRP Project 9-36 was an alternate to the current RTFOT mass change procedure for quantifying binder volatility. The SAFT included a VCS that used an air-cooled condenser to collect vapors produced during aging. With appropriate glassware, the MGRF also could be modified to use a VCS.” The findings for the SAFT method proved negative for the binder aging question. “The SAFT, on the other hand, is not an acceptable replacement for the RFOT for a wide range of binders. There is a significant difference in the rheological properties of SAFT-conditioned and RTFOTconditioned neat binders, and the difference is more apparent for higher stiffness binders.” Advanced Asphalt Technologies, LLC, performed the research in the report “Investigation of Short-Term Laboratory Aging of Neat and Modified Asphalt Binders,” now available from the Transportation Research Board. David A. Anderson, P.E., and Ramon Bonaquist, P.E., served as co-principal investigators for the project. Dr. J. Claine Petersen provided assistance with the chemistry of binder aging, and Dr. Charles Antle provided assistance with experimental design. Drs. Anderson and Bonaquist authored the report, which can be viewed in full at http:// www.trb.org/Main/Blurbs/166483.aspx. A print edition can be purchased at that link. All appendices are available in digital format at that link as well.
Use HMA to Design WMA by AsphaltPro Staff
T
he new report from the Transportation Research Board (TRB), titled “NCHRP Report 714: Special Mixture Design Considerations and Methods for Warm Mix Asphalt” is a draft recommended appendix to AASHTO R 35, Standard Practice for Superpave Volumetric Design for HotMix Asphalt (HMA). Edward T. Harrigan, Staff Officer for TRB states in the foreword that the “report provides a mix design method tailored to the unique material properties of warm mix asphalt (WMA) technologies in the form of a supplement to ‘NCHRP Report 673: A Manual for Design of Hot Mix Asphalt.’ The report will be of immediate interest to materials engineers in state highway agencies and industry.” The authors of Report 714 try to make it clear that NCHRP Project 9-43 had the sole objective of developing a mix de10 February 2012
sign method that engineers and lab techs could use for WMA. Out of that project, researchers released the NCHRP Report 691, which documents all the research that leads up to the fact: Industry does not need a stand-alone WMA mix design method that is distinct from HMA mix design methods. Researchers decided the best thing to do was develop an appendix to AASHTO R 35. The appendix is Report 714. It provides an outline for designing a dense-graded HMA and WMA including recommended improvements in virgin binder low-temperature continuous grades for RAP blending, determining nominal aggregate sizes and more. The report even offers some parameters for lab testing. Advanced Asphalt Technologies, LLC, performed the research in Report 714, which is now available from TRB. It can be viewed in full at http://www.trb.org/Main/Blurbs/166517. aspx. A print edition can be purchased at that link.
equipment maintenance
Here’s How to Adjust Dryer Flights Young offers optimum efficiency advice before and during WOA
T.J. Young of T2ASCO checks on a client’s drum.
by AsphaltPro Staff
D
uring the past five years, we’ve featured several articles about drum maintenance, including discussions of flight adjustment. We’ve lost count of the number of ads our advertisers have placed concerning flighting efficiency. Every issue seems to contain some way to help you get better results from new or different flight packages. The topic is a point of constant focus among producers, and the staff at the Association of Equipment Manufacturers (AEM) put it on the docket for World of Asphalt next month. T.J. Young of T2ASCO, LLC, will present “Dryer Flight Adjustment” in one of the People, Plants and Paving Training programs in Charlotte, so we called on him to get a preview of what he’ll teach in the session. Sandy Lender: “T.J., can you explain in a few short words why dryer flights and flighting adjustment is a topic of constant discussion in our industry?” T2ASCO: “There are four primary reasons why dryer flighting is a point of concern in hot mix production. “One: dryer flighting directly impacts fuel consumption and drying costs. “Two: dryer flighting impacts the ability of the producer to run high RAP mixes. “Three: the operating temperature of the baghouse is controlled by the drying flighting, and this affects baghouse longevity. 12 February 2012
“Four: dryer flighting is one of the ‘art’ areas in hot mix production.” Sandy Lender: “Can you elaborate some? What specifics can you offer producers who are worrying about fuel consumption or high RAP and so on?” T2ASCO: “Sure. On the first point, the efficiency of the flight design affects drying costs. Drying costs are something that all producers are trying to manage. It’s one of the few variable costs they can control in today’s tough economic times. Every 10 degrees of exhaust gas temperature reduction results in 1 percent fuel reduction. This doesn’t sound like much unless you realize that many plants are operating in a condition where they can reduce exit gas temperatures by 40 to 60 degrees. And that means 4 to 6 percent savings. When your fuel bill is one-half of a million dollars or more, this becomes a significant number. This is why you see so many ads touting fuel reduction savings through a more efficient flight design or replacement flights. “Then, if the producer wants to run high RAP mixes, this calls for a completely different flighting pattern than for virgin mixes. With most plants, you need to super-heat the aggregate to heat the RAP. The higher the RAP percentage, the more ‘aggressive’ the flight pattern has to be. If, however, you want to switch back to virgin mixes, the ‘aggressive flights’ can be too effective and drop the baghouse temperature below dewpoint. This can create moisture corrosion to the baghouse, which affects the baghouse’s life. In worst-case scenarios, it changes the dust to ‘mud,’ which inhibits the producer’s ability to return the dust to the mix, which drastically and negatively impacts the quality of the mix. “Striking a balance between these factors can be difficult, and as we move to even lower temperature mixes with warm-mix asphalt, extra pressure is applied to this situation. “The ‘art’ part comes in when learning how to change and adjust the flights in the dryer for the different operating conditions and strike a balance between the extremes. Otherwise you’re faced with constantly having to change your dryer flights, and that’s just not practical.” Sandy Lender: “This sounds like a lot to accomplish in the 90 minutes you have for your talk at World of Asphalt.” T2ASCO: “Yeah, I’m a little worried. The time constraint will keep me focused.” Sandy Lender: “What do you expect attendees to take away from your session?”
We take you on the high road. When others say they can provide you with customized solutions for your plant, Hotmix Parts & Service can ACTUALLY PROVE it. The 25+ years of proven results make us the number one choice in asphalt parts and services. So use us as your one-stop shop for maintaining, rebuilding and upgrading your asphalt plant and you will see the difference. Here are just a few of the ways we can help you transform your operation from the inside out:
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equipment maintenance These three examples show nice flighting packages.
T2ASCO: “Flighting adjustment is really not that hard. There are some common themes. Once you understand those themes, you can use whatever brand of flight to apply those themes. What I’m shooting for is to simplify the concept and make sure everyone understands these common themes. “It’s my firm conviction that you can’t consider yourself good at flighting adjustment and flighting design until you can use any manufacturer’s style of flights to arrive at the same outcome. It is possible. And then you can develop your own preferences. “It’s sort of a Dodge-Chevy-Ford thing. They all make trucks. They all haul dirt and rock and asphalt, of course. You can prefer one brand over another, but they all work. Learning to make any brand work is important. Later you can develop your own preferences when you get to select the equipment. “During the session, I’m going to show the different styles and brands of flights, show video clips of different dryers working with these flights, and discuss how to reach the same goal with the different styles and brands of flighting. “I expect attendees to walk away confident enough that they will feel like they can start ‘playing’ with their flights to arrive at their own plant’s optimum performance. Much of that is getting over the fear of negatively impacting the dryer performance. That fear is abated with understanding these common themes I mentioned. Once attendees lock in on these principles, they can take off running and start making adjustments with confidence on their own. They’ll know where they need to go and how to get there. “Another thing I’m going to try to impress on everyone is that flights wear out. So after you get this all worked out, everyone needs to understand that these are just like tires, brakes and shocks on your car. They begin to wear and degrade the minute you put them in service. We have to keep re-investing in our dryers for optimum efficiency. We have to stay on top of their condition or we’ll slide back to less than optimum performance. Production, RAP percentage and drying costs will all suffer. “The good news is that the benefits of a good flight package more than pay for the initial cost of the flights and the maintenance costs it takes to keep them in tip-top shape.” (See sidebar above.) 14 February 2012
Sandy Lender: “Can you give readers a specific example of a true-ism or best practice you’ll talk about at World of Asphalt?” T2ASCO: “Sure. This is one no one is going to expect. Only those who read your article will be in-the-know. “Before you start adjusting your flighting, you have to know what your true operating temperatures are. In our industry, we use aggregate or mix temperatures and baghouse operating temperatures as an indicator of efficiency and whether flights need to be adjusted or not. This is just ‘what we do.’ You can lose a lot of heat between your dryer and your baghouse. “From the 60-some plant audits I did this year, I can statistically tell you that more than one-third of them had worn flop doors in their entry chutes, flop doors without enough ‘counter-weight’ to them or worn seals around their high speed slinger conveyors masking their true dryer exit gas temperatures by 30 to 50 degrees. “The word on the street is that when your baghouse temperature starts to fall, you take the flights out to raise the baghouse temperature. But what if the baghouse temperature is artificially low from outside ‘tramp air’ being drawn into the system? “One of the first things I’m going to impress on everyone in Charlotte is that, based on my experience, over one-third of the plants in the field have this problem. It’s because everything wears out on the plant, and dryer seals wear out, too. These wear very slowly over time so the impact is not obvious overnight. When you change to a different mix or the weather changes drastically, all of a sudden you notice the problem. “So we have producers removing flights to protect their baghouse temperature to keep it above dew point, and they’re inadvertently raising their drying costs and reducing their dryer’s ability to dry effectively on wet days, particularly with big rock or high RAP mixes. That’s the ‘acid test’ for a set of dryer flights. Those producers are moving themselves in the wrong direction. “Let me give you a specific example. “I helped one producer this year with a plant conversion. He had an old batch plant that we made into a continuous mix production plant. His dryer needed a completely new set of flights. I used Gencor style adjustable flights.
equipment maintenance No endorsement here; the operator was familiar with them, understood how to adjust them and wanted to use them. I wasn’t going to be around to help tune the dryer later, so I helped him arrange the purchase with his preferred vendor, and told him to call me when he got ready to start up in the spring to tune the flights. “The maintenance team installed the flights while he wasn’t there in the traditional alternating ‘spill/carryover’ pattern without calling anyone. However, they didn’t know, nor did the operator know, that these particular flights were designed for a higher shell speed. His dryer turned more slowly than this. I expected to coach him in a different direction on the pattern, with more carryover configuration settings, but never got the chance. I will discuss the difference between these two positions specifically in the seminar. “His baghouse inlet temperature was too cold, so he started adjusting the flights to more ‘spill pattern’ to raise his baghouse temperature. This is the opposite direction he should have been going with a slow shell speed. Then he called for help because his mix production was restricted on wet days and his shell was getting too hot. “The bottom line was that they never got around to sealing up his dryer inlet chute properly, as they were instructed. After a considerable amount of coaching, this was accomplished, his baghouse temperature immediately shot up 50 degrees, his production rate went up 40 tph on his wet aggregate, his problem was solved and he was set up to go about adjusting the flights for more performance. “This is not an isolated example. Like I said, I’ve seen this on about one-third of the plants I’ve audited this year. Three other contractors I work with have the same style counterflow drum mixers in three different regions in the country. In each case, they were removing flights to raise their baghouse temperatures, but after replacing the worn slinger seals, their baghouse inlet temperatures rose 35 degrees. “Fixing leaky or improper seals typically results in increases in baghouse temperature in the 20- to 30-degree range. The examples I’ve just mentioned are real, but more extreme.
Manage dryer seals, flop doors and slinger seals before you think about adjusting flights. Temperature problems could be solved with simple maintenance rather than flight pattern changes. 16 February 2012
A
B
C
D
The four flight styles shown here are merely a sampling of what producers have installed. As mentioned before, the benefits of a good flight package more than pay for the initial cost of the flights and the maintenance costs it takes to keep them in tiptop shape. A = flights from Astec Industries; B = flights from CMI/Terex; C = flights from Gencor Industries; D = flights from Standard Havens
“A key point I’m going to impress on everyone is to make sure they manage their dryer seals, flop doors and slinger seals before they think about adjusting their flights. “Then we’ll get into the different styles of flights and how to create what I call ‘spill/carryover’ pattern with each design to balance the exit gas temperature differential, which is the exit gas temperature on the uphill side of the drum, versus the downhill side of the drum. “The next step will be learning how to loosen the veil or tighten the veil to control the overall exit gas temperature. “Obviously we don’t have room to outline it all here, but this is the basic outline of the program. I think everyone is going to be pleased. We’re looking at key basic concepts and will discuss how these same concepts are applied with different brands and styles of flights. Attendees should be able to manage their own drying flighting very successfully afterward.” Sandy Lender: “We plan on being there. When World of Asphalt is over, we want to go to the field and adjust flights with you.” T2ASCO: “Absolutely! Just remember your PPE.” Sandy Lender: “Safety gear is first on our list. In fact, does entering the drum for flight adjustment or leak detection require a confined entry permit or confined entry training?” T2ASCO: “Yes, it does. You should always follow confined space protocol when entering a drum.” T.J. Young is president of Technical Training and Advisory Services Company (T2ASCO). One of the three presentations he’ll give at WOA this year is on dryer flighting. For more information, visit his website at www.hotmixproduction.com.
equipment maintenance
Batch, Dratch Winter Checklist by Cliff Mansfield
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ith winter weather comes time to perform needed maintenance chores at the asphalt plant. When setting up a plan of attack some people find it helpful to use a checklist to determine which items need special attention and which ones need only regular servicing. What follows is my inspection protocol, which can be used to formulate a schedule for a plant maintenance and repair regimen. We’ll concentrate on the batching tower and its specific requirements. As you perform these inspections keep a clipboard handy to note any needed repairs. Marking paint is also useful to highlight units in need of attention. Keep in mind, I’m not familiar with every conceivable combination of equipment in our rapidly changing industry. Omissions are bound to happen. This article is intended as a guideline and in no way professes to be the last word on the subject. Feel free to delete or add sections as needed to suit your particular application. Remember to follow Occupational Safety and Health Administration (OSHA) lockout, tagout regulations during these inspections. Also remember your general maintenance activities at this time. Maintenance personnel should examine all gearboxes and speed reducers and note those that need repairs. It’s a good idea to schedule each box for an oil change during the winter months. Collect properly marked samples from each box and give them to a reputable oil analysis company that will be able to detect any abnormalities. Personnel should also complete a thorough greasing regimen prior to plant restart. For electric motors, follow the manufacturer’s recommendations. Each year motors fail because uninformed service personnel pump them full of grease like they would a troughing roller. Some motors vent excess grease internally, so once enough of the stuff is pumped in failure is bound to follow. Remember that most motor manufacturers recommend a yearly greasing schedule that consists of one or two pumps of the gun. Read and follow their guidelines. Make sure you check all wiring and junction boxes for any condition that could render the workplace unsafe. Mark anything that is substandard. Also see to your housekeeping activities to keep the workplace safe. A clean place to work, statistically, has fewer accidents that one covered in grease and accumulated debris. Remember that state plant inspectors and officials from the DEQ will likely look more favorably upon a clean, neat facility than one with safety hazards and leaking parts. 20 February 2012
This 5,000-pound batch plant is located in Washington State. Rust is a by-product of working in the Northwest, but vendors are always willing to quote a price to prep and paint with high-temperature paints suitable for the HMA plant. While the plant in this picture is in no danger yet of losing integrity or experiencing leaks, rust is something to watch on ductwork and temperature-sensitive joints where dust and heat need to stay inside.
HOT STONE ELEVATOR
Hot elevator chains operate in a very hostile environment. Heat, dust and stress all work together to promote wear. Unless we track that wear and address it at the appropriate time, things can come shuddering to a halt. When the bucket-line breaks, digging out the 300-degree rock, untangling the piled up chain and making the needed repairs is a time consuming chore—one most of us would rather avoid. An inspection, using a critical eye, can go a long way toward dodging the proverbial bullet. Begin by removing all access and inspection doors. 1. Perform the external inspection first. Look for thin metal, dust leaks and obvious structural damage. 2. Remove the guard and inspect the hot stone elevator’s drive system. Chain drives are common. If your unit uses this method of propulsion it is important that you inspect the chain for excessive wear and both sprockets for any signs of damage. Look for a condition called “fish eyeing,” or cupping on the load side of the teeth. M a r k any abnormalities you find. If your unit is belt driven, you need to look for cracked or glazed belts, excessively worn sheaves and a loose condition that requires adjustment. 3. Examine the motor and gearbox for any abnormalities. Mark for attention anything that raises doubts. 4. Inspect both upper bearings. Use a bar to pry the shaft around. With the weight of the chain on the shaft, this operation will require considerable effort. 5. Look through the access door and examine the top sheave. On friction drives look for irregular wear patterns,
breakage or looseness. For toothed sprockets look for excessive wear, fish-eyeing and obvious damage. 6. Some elevators use idlers. It is essential that each one of these receives an exacting examination. Idler shafts have been known to break, and under certain conditions stall the elevator. On sprocket driven units the bucket chains have broken as a result of the impact with the idler shaft. Look at each idler. Bent or grooved shafts and worn wheels must be scheduled for repairs. 7. Look at the tail shaft and traction wheel. Is the wheel egg shaped? Is it worn out or loose? Are the bearings in good condition? Do the adjusters work? How about the shaft’s dust seals; are they working? Mark anything that needs attention. 8. Look at the individual chain links. If they are worn to the pins and the side bars abraded to knife edges, you don’t want to head into a paving season with them. When ordering hot stone elevator chain, get the best you can afford. I know of no other situation where the adage “You get what you pay for” applies as well as this. 9. Last, examine each and every bucket. Look for excessive wear, cracks or missing bolts. Any severely distorted bucket is a liability and should be replaced. 10. See the general maintenance discussion at the beginning of the article.
SCREENS
The screens are very important to the operation of a batch plant. In my opinion, they are the only reason to own a batch plant as opposed to a drummer. Any examination of this unit should be done with an eye toward efficiency. 1. Start with an external inspection. Look for missing parts, such as lid hold-downs, and for signs of dust leaks. Look at the skirting seals under the units. Are they there or long gone? Examine the top covers. Are they worn out where they rest on the frame or other lids? All these conditions should be addressed. Check to see that the screens move freely. If they don’t, look for a buildup of aggregate under the drive end. Check the size of the material. If it’s a useable size that normally goes into a hot bin the accumulation could point to leaks in the oversize discharge, exacerbated by screen flooding and carry-over. Often, this condition can be addressed by repairing the leaks and reversing the screens so that they throw the material back toward the hot elevator. This makes the material stay on the screens a bit longer, giving it time to work through the screen cloth. This same approach can sometimes solve sampling problems, which are caused by carryover at higher production rates. It’s not uncommon for a plant operator who has his machine calibrated and in spec
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equipment maintenance at a certain tons-per-hour rate to find he is being forced to run his plant ever faster to meet production demands. As production rates increase, so does the carry-over rate. Under the right conditions the finished product can go out of spec, leading to hair pulling and a midnight recalibration session. If you’ve experienced this scenario, try reversing the screens. This should produce a more consistent mix through a wider range of feed rates. 2. Next, remove all the lids and side covers. It’s a good idea to take a fire hose and clean the accumulated fines off the screen frames and springs. It makes it much easier to find damaged and cracked components. Caution: Remember to open all the gates below and provide a way for the water to escape from under the plant. Once the unit is clean you should inspect it for broken springs and cracks in the framework. 3. Closely inspect each screen cloth. Look for excessive wear and broken wire. Check the screen trays. Are they all tight? Is the screen cloth secure? It’s good insurance to stock a complete change of screens. When stored in a custom built rack on the screen deck, they are ready for installation with a minimum of fuss. Don’t forget to keep a supply of the appropriate bolts handy. 4. Examine the screen drive and eccentric. Follow the manufacturer’s recommendations as to periodic maintenance. In general, you should look for damaged components, worn sheaves or belts and broken motor mounts.
HOT HOLDING BINS
1. Inspect the inside of each bin. Look for thin metal, missing partitions and any structural damage. Check the overflow chutes and hats, if used, for leaks. Schedule maintenance on anything amiss. Look at the bin dividers. Do they go up close enough to the bottom of the screens to prevent cross-bin contamination? 2. Check the gates and their pivots/rails. Do they work freely? Are they excessively loose? 3. Examine the air cylinders. Check for leaks or loose rod and pivot bushings. 4. Schedule the air solenoids for kits and cleaning. The same for the air oilers. Spare solenoids, air lines, a cylinder and an oiler might possibly shorten downtime in the event of a component failure.
AGGREGATE WEIGH HOPPER
You examine this unit in essentially the same manner as you would the hot bins with the exception of the weigh system. 1. Check the basic iron for thin spots. 2. Check the gate and its pivots/rails. 3. Check the air system. Again, schedule the solenoid and oiler for kits and cleaning. Weigh system 1. Begin by cleaning all the knives/pivots. Use compressed air. Do not lubricate them once they are clean. 22 February 2012
2. Inspect all knives and pivots. Look for loose, missing or misaligned components. If you find anything wrong contact a reputable company that specializes in scales. Have the scales repaired and calibrated. It’s best to schedule this activity for a time when all other repairs to related equipment have been completed. The addition or deletion of metal in the weigh hopper can drastically affect calibration.
ASPHALT OIL INJECTION SYSTEM
Generally, two types of oil injection systems are in use: Gravity feed and forced feed. The checklist for the weigh system and for the asphalt oil bucket is nearly the same for both systems. The gravity system has a clapper valve and some associated air controls. The forced feed system uses an injection pump, which we will address last. Asphalt oil buckets 1. Examine the exterior of the unit. Is it covered in asphalt? If so, from where? Is it caused by overflows which could be pointing to a problem with the scale read-out and its signal to the blending computer, or possibly from a sticky fill valve that occasionally fails to shut off when told to do so? 2. Check the heat transfer oil system for the bucket. Does it leak? Does it work? Check to see if the hot oil lines are binding the bucket, possibly resulting in inaccurate readings. If so, schedule repairs. 3. Examine the clapper valve on the gravity system. Does it fit properly and seal? Are the pins worn out? How about the air cylinder; is it worn out? Air lines in good shape? As with all the other solenoids and oilers, it’s a good idea to schedule those on the oil injection system for a cleaning session and then install tune-up kits. 4. Check the spray bar where it enters the side of the pugmill. Is it free or does it bind? Under the right conditions a binding spray bar can lead to abnormally high oil contents. You should look for an accumulation of material between the bottom of the spray bar and the side of the pugmill. This material can restrict the downward movement of the oil bucket as it fills and cause the scales to read lighter than the amount actually in the bucket. Any build-up here should be scheduled for removal. Oil bucket fill system 1. Check the overall condition of the valve. Is it leaking? How about its connections? Does the heat transfer oil system work? Does it leak? 2. Examine the air actuation system. Use the same criteria to evaluate it as we’ve used throughout this inspection. Weigh system This procedure is the same as the one for the aggregate weigh system detailed above. As with the aggregate scales, it’s best to schedule this activity for a time
when all other repairs to related equipment have been completed. Oil injection pump 1. Check the pump and all its lines. Schedule any leaks for repairs. 2. Check the drive system. Some pumps use couplers and a direct drive motor; others use a belt drive while still others are driven by a chain off the pugmill itself. Whatever method yours uses examine it for the same flaws we’ve discussed on other units, such as fish-eyeing, worn sheaves/belts and couplers. 3. On units that use a vacuum breaking valve to control emptying the weigh bucket you should check it and its operating system for any problems. For air operated systems start by checking the air cylinder. Is it worn out? Are the air lines in good shape? As with all the other solenoids and oilers, it’s a good idea to schedule these for a cleaning session and then install tune-up kits.
PUGMILL
Follow OSHA Lockout-Tagout regulations before inspecting this potentially lethal unit. 1. Remove the inspection doors and examine the interior of the unit. Look for excessively worn shanks,
tips and liners. Slate cracked or broken components for immediate replacement. 2. Check the asphalt injection spray bar. Are all the spray nozzles in place? (See note 1 below.) Is the bar worn thin on the top where the aggregate from the weigh hopper cascades over it? (See note 2 below.) 3. Examine the mainshaft bearings. Again, use a bar to pry the shafts around. Mark for replacement any bearing you are in doubt about. 4. Inspect the drive assembly. With chains, look for fisheyeing and excessive wear. For belt drives look for glazed or loose belts and worn sheaves. Special attention should be given to those units that use shaft couplers. Check for any signs of damage or movement. Again, when in doubt replace them. Failure of one of these devices on certain pugmills can throw the timing off, resulting in catastrophic damage to the machine. Note 1: Several oil-related problems plaguing hot mix manufacturers can be traced back to the spray bar. Sluggish emptying of the weigh bucket can result in slowed production rates. This usually leads to the removal of some of the spray nozzles in an attempt to speed things up. This, in turn, leads to the second, potentially more damaging issue.
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equipment maintenance Spray nozzles control the distribution of oil in the mixer. If adjusted and sized properly, spray nozzles distribute the oil uniformly throughout the pugmill. If set-up incorrectly, or removed altogether, the nozzles can give a spray pattern that produce lean or rich spots in a particular batch of mix. If the state’s QC inspector gets mix from a lean spot and his results reflect a low oil content, the operator adjusts the oil upward to avoid going out of spec. If, on his next test, the QC inspector pulls the sample from a rich spot, the resulting jump in oil percentage could easily put a plant out of spec and into penalty territory. If the swing is bad enough it could result in a mandatory shut-down and plant recalibration. Put quite simply, all of this could be due to an easily addressed oil distribution problem in the pugmill. Using a slat conveyor, batcher and holding silo usually eliminates this problem. However, for those plants that operate without a silo the problem can easily put you into an adversarial situation with the state DOT because all the data you have (tank stickings and quantities used over time) shows that you are, in fact, putting in the correct percentage of asphalt oil. Unfortunately, both you and the state would be right under these conditions. But the state has the final say, making it best to avoid the situation from the start. I advise my clients to only remove or modify spray bar nozzles when they thoroughly understand what result that
action will have. If you are experiencing distribution problems like those discussed earlier, analyze the issue. Once you see what’s going on, don’t be afraid to experiment. In general, you want to be sure that oil comes out the farthest end of the spray bar from the weigh bucket. If you must plug nozzles to get the oil to the far side, start with the one closest to the weigh bucket because it gets oil first and has it last. Note 2: The addition of a trough on top of the oil spray bar to catch and hold a quantity of aggregate can go a long way toward eliminating wear on this item. Try a 6" x 1" x 1/8" channel iron. Have it welded to the top of the bar, the uprights pointing skyward. Overall, inspection of the dratch or batch plant resembles that of the drum plant on a smaller, but not less observant, scale. Maintenance personnel have to stay on their toes and watch for leaks and wear any time of the year at any type of HMA plant. Take advantage of the slower winter months and scheduled downtime to make sure your operation is ready for a successful start-up this spring. Cliff Mansfield is an asphalt plant engineer and a freelance writer specializing in asphalt plants. Contact him at C.M.Consulting www.hotplantconsulting.com or (541) 354-6188 or through the Ask the Plant Expert button at www.TheAsphaltPro.com.
Get NCAT Info First-Hand combining the two environmentally friendly practices— producing high RAP content mixes with WMA technology—will also be shared. our research cycles have been completed on the Research during the fourth cycle also included usNCAT Pavement Test Track since its inception in ing alternative binders and binder modifiers, such as a 2000, each culminating in a set of innovative, implehigh-polymer modifier, to reduce the quantity of asphalt mentable findings for the asphalt paving industry. NCAT materials needed for construction and, thus, lower conengineers and state highway agencies will share the restruction costs. Other studies sults from the most recent cycle, looked at the structural con2009-2012, at the Pavement Conserving energy and tribution of open-graded fricTest Track Conference in Auresources during asphalt mix tion course (OGFC) surfaces, burn, Ala., Feb. 28 through 29. also known as porous friction The test track sponsors have design and construction was course; lab tests to predict specific research objectives for an overall focus. permanent deformation and their sections, along with shared cracking resistance; calibratgoals for the track as a whole. ing and refining mechanistic-empirical pavement design In the 2009 cycle, conserving energy and resources during models; and more. asphalt mix design and construction was an overall focus. In addition to hearing the most significant track reFor example, several sections evaluate the performance search results from the previous cycle, conference atof mixes that include either moderate (20 percent) or high tendees will also have the opportunity to tour the test (45 to 50 percent) amounts of reclaimed asphalt pavement track and hear plans under way for the 2012 to 2015 (RAP). Results from those sections will be discussed at the research cycle. For more information on the 2012 NCAT conference, as will the findings from sections constructed Pavement Test Track Conference, visit http://www.ncat. with one of two warm-mix asphalt (WMA) technologies: us/newsroom/2012-track-conference.html. mechanical foaming or an organic additive. The benefits of by Buzz Powell
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24 February 2012
producer profile
Blend, Report, Improve Construction Resources Management finds more ways to automate quality for P&D, NEA by Sandy Lender
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utomation at the asphalt plant makes production easier for operators. Blending systems are designed to take human error out of the equation, offering repeatability for every load that leaves the plant. Rick Moulton is the supervisor of plant systems and automation at Construction Resources Management, Inc., (CRM) and he will tell you that most blending systems do a good job of making mix. “Unfortunately, most fall short at reporting,” he said. For Moulton and CRM, a captive service provider for Payne & Dolan, Inc., (P&D) and Northeast Asphalt, Inc., (NEA) substandard reporting won’t fly. Each company CRM supports has multiple hot mix plants to keep track of. That means Moulton needs system technologies that will keep up with the times, as any owner reading this also needs. Here’s how Moulton is solving his blending and reporting requirements, and how his technology continues to evolve with the help of vendors like Systems Equipment, Ic., Waukon, Iowa. “Most of our plants use Systems’ ADP-100/XP-100 setup,” Moulton said. “The ADP does the blending and the XP, the graphical user interface (GUI), makes running the blending system easier and records production data.” He explained that the companies have been using the ADP-100 blending controls since before he joined the team; they added the XP-100 a few years ago. “I’ve been with the company since 1999 and we’ve been running the Systems’ ADP, or its predecessors, as long as we’ve had drum plants. It works the same way now as it did then; they didn’t mess with a good thing. With the addition of the XP-100, which is the Windows 26 February 2012
Using the ADP-100 blending system and XP-100 reporting software from Systems Equipment has made production more efficient for producers.
“The GUI can give management recorded information, but they want it to do so in a more immediate fashion.” — Rick Moulton PC front end for the ADP, the blending system is now able to record and archive certain production information that we can report against.” The improvements Moulton looks for are those that give management at P&D and NEA immediate information. As he explained, “We aren’t looking to fix something that isn’t broken. We are improving the parts that tell us what’s going on. You can’t control what you can’t measure.” Moulton spoke with confidence in Systems’ products. “The ADP/XP blending system is very reliable. The folks at Systems are always available to us and do everything necessary to help us continue to produce quality mixes. We continue to work closely with the people at Systems Equipment, coming up with improvements that help our business objectives.
“The ADP controls the mixing process. We give it a recipe and it mixes to that design. The GUI can give management recorded information, but they want it to do so in a more immediate fashion. That’s where the thought of an upgrade in communication comes in. The focus now is to be able to find out what each plant is making, and how well it’s running, as close to real-time as possible. They no longer want to wait for some generic paper report to be printed at the end of the day and mailed to the office.” Currently Moulton can get to this information at the plant on demand, but not yet over the company’s computer network. “We’ve been hesitant to just plop the blending system computer on our network for fear viruses or other malware might interfere with production. Most people
don’t realize how much goes into securing data on a network or the Internet. The blending system controls big, moving, mechanical parts. If an office computer gets a virus, a few files may be lost. If our blending system gets a virus, the plant stops making mix or someone could get hurt. We’re working on ways to secure the XP computer without getting in the way of making quality mix. In the near future, with the help of our IT staff and some better malware protection, we hope to get near realtime telemetry from at least a couple of our plants.” Moulton explained that when this project goes online, management will have direct access to XP-100 production data. Considering all that the system tracks at the plants, getting up-to-the-minute information at the office will be invaluable. At this time, the Systems Equipment HMA blending systems track up to 16 bins at a plant, allowing producers to include RAP, RAS, WMA additives and other ingredients that may be required for a quality mix. The ADP system meters these prod-
ucts to effect the proper mix design as the plant operator selects the recipe from the GUI’s database. In the event the operator needs to make a change in the recipe, he can direct the system as desired. “The system allows the operator to change the recipe as directed,” Moulton explained. “The operator changes the percentages of the included ingredients, and the blending system does the calculations, and then changes the signals it sends to the metering devices.” When it comes down to it, the result of CRM’s secure network with Systems’ XP-100 reporting will be better and more timely communication. “Safety, quality and productivity all rely on the right people having the right information at the right time. Our operators are amazing communicators. A big part of my job is to strive to give them the best tools available to do just that. Anyone who is in charge can only benefit from knowing what’s going on at any time. Any improvement in technology that helps to that end is invaluable.”
The Northeast Asphalt plant in Neenah, Wis., goes about business as usual on an ordinary day thanks to automated systems and reliable reporting. It’s a good day when everything goes as planned. www.theasphaltpro.com | ASPHALT PRO 27
Determine Dynamic Modulus, Flow Number with AMPT by NCAT Staff
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ith the development of Superpave mix design, there arose a need for simple performance tests to accompany the new design system. The Asphalt Mixture Performance Tester (AMPT) can be used to perform two tests recommended by NCHRP 9-19 to address this need: dynamic modulus (E*) and flow number (Fn). E* is primarily used for hot mix asphalt (HMA) materials characterization for pavement structural design using the Mechanistic-Empirical Pavement Design Guide (MEPDG), while Fn can be used to indicate rutting resistance. Note that AASHTO recently adopted the MEPDG as the new standard for pavement design. Many states will transition to the new system in the coming years while states like Indiana have already made the change. The MEPDG, now known as DARWin-ME under AASHTO, relies heavily on AMPT testing to provide primary asphalt concrete material properties. States that make the transition will need extensive AMPT testing of their materials for structural design purposes. Both E* and Fn, also known as repeated load deformation tests, are
Figure 1. The AMPT equipment costs about $65,000 and includes highly accurate systems for loading, measuring deformations and controlling test temperatures. 30 February 2012
Figure 2. Flow number test data
performed on compacted asphalt specimens using either the AMPT or a servo-hydraulic testing machine that can produce controlled sinusoidal compressive loading. The AMPT equipment (Figure 1) costs about $65,000 and includes highly accurate systems for loading, measuring deformations and controlling test temperatures.
Flow Number Testing
In the Fn test, a specimen is subjected to repeated axial compressive load cycles, each consisting of a pulse load applied for 0.1 second, followed by a rest period of 0.9 second. Permanent axial strain is measured as a function of the number of load cycles. Flow number is defined as the number of load cycles corresponding to the minimum permanent strain rate, as shown in Figure 2. A higher flow number indicates a more rut-resistant mix. The Fn test is performed on three replicate specimens that are 150 mm high and 100 mm in diameter, accord-
ing to AASHTO TP 79-09, Standard Method of Test for Determining the Dynamic Modulus and Flow Number for Hot Mix Asphalt (HMA) Using the Asphalt Mixture Performance Tester (AMPT). Specimens may be obtained by coring gyratory-compacted samples and trimming each end of the sample. Fn is usually conducted at the 50 percent reliability pavement temperature for a given location as determined using the LTPPBind software. A confining pressure of 10 psi is sometimes used for Fn testing, and research continues to evaluate whether unconfined or confined testing better simulates field conditions. The test takes about three hours per specimen, and the AMPT software automatically calculates the flow number.
Correlating Fn with Field Performance
Previous studies, including mix samples from WesTrack and from the FHWA’s Accelerated Loading Facil-
Once the shifts are made, the effect of temperature and loading frequency is represented by a reduced frequency, which accounts for the effects of temperature and frequency simultaneously.
Dynamic Modulus and Pavement Design
Figure 3. Stress and strain recorded from a dynamic modulus test
ity (ALF), have shown reasonable correlations between Fn and field performance. These correlations are necessary for establishing acceptance criteria for the mix design process. A study using data from the 2006 research cycle of the NCAT Pavement Test Track also showed moderate correlations between Fn and field rut depths at 5 and 10 million equivalent single axle loads (ESALs). The flow number test shows promise as a performance test for evaluating mix designs such as warm-mix asphalt and high RAP content mixes. However, more research is needed to determine appropriate Fn acceptance criteria based on further correlations with field performance.
Dynamic Modulus Testing
Because HMA is a complex composite material that exhibits thermo-visco-elastic behavior, its modulus is highly dependent on temperature and rate of loading. For example, a mix’s stiffness may change drastically from summer to winter. For visco-elastic materials such as HMA, a cyclic loading test is necessary to characterize how its properties are dependent on the rate of loading. In the dynamic modulus test, sinusoidal axial loads are applied to a cylindrical specimen. Stress and strain are recorded, as shown 32 February 2012
in Figure 3, and dynamic modulus is calculated by dividing the peak stress amplitude (σ0) by the peak strain amplitude (ε0). Phase angle is also obtained from the E* test, which is a function of the time lag (Δt) between stress and strain. E* testing using the AMPT is conducted in accordance with AASHTO TP 79, which requires testing at three temperatures: 4°C, 20°C and a high temperature depending on the performance grade of the binder used in the mix. Testing is conducted at three frequencies between 0.1 and 10 Hz for 4 and 20°C, and at four frequencies between 0.01 and 10 Hz for the high temperature. Three replicate specimens are tested, and the results are averaged. The entire AMPT procedure, including specimen preparation, requires 15 to 30 hours of technician time. After the test is completed and the results of the replicates are analyzed for consistency, the E* data are shifted using the time-temperature superposition principle to construct a master curve at a reference temperature according to AASHTO PP 62 and PP 61, respectively. The time-temperature superposition principle is a way to relate modulus values of a material obtained at different temperatures and frequencies. E* data from different temperatures are shifted horizontally on the graph of modulus versus frequency to form a single continuous curve.
E* is one of the primary material inputs for designing flexible pavements using the MEPDG. The MEPDG uses E* at various temperatures and loading rates to calculate pavement strains, which are used to predict pavement distresses related to environmental conditions and traffic speeds. Three levels of design analysis exist within the MEPDG: • Level One—uses laboratorymeasured E* data to develop the master curve • Level Two—uses predictive equations to develop the master curve • Level Three—also uses predictive equations to develop the master curve Several empirical equations have been developed to predict E* based on aggregate gradation, mix volumetrics and binder properties. Using data from the 2006 research cycle at the NCAT Pavement Test Track, comparisons were made between three E* predictive equations (Witczak from NCHRP 1-37A, Witczak from NCHRP 1-40D and the Hirsch model) and laboratorymeasured E* values. The Hirsch model proved to be the most reliable model for predicting the E* of an HMA mix. E* is also a useful property to compare stiffnesses of different asphalt mixes. For example, it could be used to compare an asphalt mix with two different grades of binder, or to compare WMA to HMA. The E* test has also been evaluated as a direct performance test for predicting rutting or cracking performance of asphalt mixes. However, the correlations with field performance have not been satisfactory because the strains involved in the test are very small.
Visit us at booth 1911
1 Convert old parallel flow drums to counterflow
2
mixer technology 2 Replace high wear dryer/drums with long lasting designs featuring the latest flighting technology
3 Add a Stansteel Rotary Recycle Mixer
5
massive steam explosions with 4 Reduce the Custom Stansteel Progressive
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Metering and Proportioning SystemTM Add multiple recycle/shingle bins
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Install a custom recycle system new, used or reconditioned
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Revolutionize warm mix with the Accu-Shear and other advanced in-line blending systems
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Here’s How to Quality Control Your High RAP
This is the Eagle Crusher 120025CC processing RAP. It’s similar to the 1400-45CC that J.D. Ramming uses for their RAP processing. Photo courtesy of Eagle Crusher.
by AsphaltPro Staff
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t J.D. Ramming Paving Co., Ltd., Austin, crews have been using recycle from the beginning. President Chuck Fuller stood before a modest crowd during the “High RAP/RAS Experience” educational session during the 57th annual meeting of the National Asphalt Pavement Association (NAPA) in Palm Desert, Calif., Jan. 23, and recommended fractionating recycled asphalt pavement (RAP). “We use Eagle Crusher screening and sizing equipment to control sizing,” he said. He explained that it’s not enough to size recycle material and substitute it for virgin material in mixes; you have to take care of the material you’re working with. “We watch three important aspects of recycle management for mix quality control.” 1. Get the moisture out of the material. 2. Know the exact material properties. 3. Treat all recycle products like virgin materials. To accomplish aspect number three, the crews at J.D. Ramming run daily quality control tests on all stockpiles, including four different RAP piles. “We keep the RAP piles apart to make sure we keep the material separated,” Fuller explained. Here are the four piles they’ve designated at their plants.
34 February 2012
1. Plant Cleanout 2. City Entities 3. P401 4. Interstate/Hwy As you can guess, the plant cleanout stockpile contains all the overrun and test mix around the plant. The city entities pile has a variety of mixes in it from around the county. Fuller said they can’t always be sure of the binder or aggregate used in those mixes, so they keep the millings in their own pile for commercial use. The P401 pile has the high asphalt cement and modified binder content of the airport millings. And the interstate pile has the PG76-22 binder millings. Fuller stressed that producers should have multiple bins when working with multiple RAP piles to keep quality a priority. The recycled asphalt shingle (RAS) pile needs its own bin, too. “In Texas, the spec calls for 95 percent passing the 3/8inch when grinding RAS, but we pay to double-grind and sometimes triple-grind shingles to get them to 100 percent passing. You’ll see moisture in the RAS, and you want to get that down below 7 percent. That means slow down production to get the RAS dry.” These are just a few ideas J.D. Ramming has implemented to keep high quality control for high RAP mix designs. Fuller was generous in sharing what he thinks can help anyone in the recycle marketplace.
Ermont operators used a TSM 28 continuous plant to create a mix with Evotherm DAT H5® at 350 tonnes per hour.
Ermont Applies Evotherm® WMA French motorway serves as positive testing ground for warm-mix performance by Frédéric Delfosse
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n Europe, the most common process for creating warm-mix asphalt (WMA) is to add an additive during mix production. EUROVIA and MeadWestvaco have been working together since 2006 in the development and promotion of WMA and, since then, nearly 1 million tonnes of WMA have been manufactured and applied on different types of roads, in different climates, and with various types of aggregates and asphalt binders. This article concentrates on a challenging project on Motorway A35 around the city of Strasbourg, France, near the German border. Ermont, a division of Fayat Group, used WMA in the construction of three courses. The mix design incorporated 10 percent RAP materials with 4.1 percent 35/50 pen virgin binder, which is similar to a PG 70-22 binder in the United States. It also featured 12 percent Evotherm DAT H5® diluted (0.3 percent content) and limestone aggregates. 38 February 2012
The average production/manufacturing temperature was between 115 and 125oC, which was more than 50oC less than the HMA control. Baghouse temperatures remained between 106 and 109oC. Construction began when ambient temperatures were around 10oC and compaction was complete when the mat had cooled to around 85 to 90oC. Ermont operators used a TSM 28 continuous plant to produce mix containing Evotherm DAT at 350 tonnes per hour. They ran the burner at 20 percent and consumed fuel at 1,380 to 1,500 liters per hour. During the manufacture of hot mix, around 165oC, the Ermont crew typically sees fuel consumption of 2,200 liters per hour, so we estimated a fuel savings on this project of about 34.5 percent. As our colleagues in the United States have seen, the first obvious benefit to using WMA is the reduction in the consumption of energy when manufacturing the bituminous mixes. The materials need to be heated less than when manufacturing conventional bituminous mixes.
Figure 1. Rheological Analysis of Asphalts Evotherm DAT is a warm-mix process based on the addition of a chemical package in an aqueous phase. The mix tech merely makes an aqueous solution with between 10 to 15 percent in weight of additive. The producer used Evotherm H5®, which is water soluble without the need to adjust the pH of the solution. To make the solution, the producer has two options. He can either inject the dilution in-line into the bitumen at a rate of 5 to 10 percent in weight relation to the bitumen while fitting a branch to the bitumen line with a pump and flow meter to inject the diluted additive, or he can use two pumps to make the in-line dilution. This graph represents the evolution of the complex modulus after extraction (the descending curves) as well as the phase angle of the two binders (the ascending curves). We observed no real For this particular project, the difference between the two asphalts. producer chose the latter. He used one pump for the water and the other pump for the H5 additive to make an in-line diluTests Show Conformity tion. (See image at left.) To control the manufacturing processes, we took samples Once the mix was made, the paving team applied 14,000 in the plant just after production. To evaluate the mechantonnes in three lifts on the A35 motorway. Each lift was 8 to ical properties of the mixes, we took one core for each 11 cm thick and applied with only one finisher on the total layer and each track for the hot mix and the warm mix the width of the three tracks of the road—8.6 meters. The crew day after the laying. We performed the following tests of achieved compaction with 12 passes of two CC422 Dynapac manufacturing control: cylinders (VT2). Void contents measured on the jobsite after • Binder Content compaction were situated between 6 and 9 percent voids. • Binder Analysis After Extraction
Follow the Temperature Gun
One parameter of interest that we wanted to follow was the evolution of the temperature of the mix on the jobsite and the evolution of the percent void content inside the mix according to the temperature and compaction pattern. We followed a truck from loadout, with mix temp of 122oC, to arrival 90 minutes later. Its mix’s temp inside the hopper was 119oC; behind the screed at 10 cm (4 inches) thick its temp was 115oC. Compaction remained effective with the mat temp at 85 to 90oC through high wind, wet conditions and an ambient temp of 14oC. By sinking a thermocouple into the mat about 5 cm (2 inches) from the top, we noted temperature versus time and discovered: the temperature decreases about 1 degree C per minute. (See “Evolution of the Void Content During Compaction” below.)
penetrability 1/10 mm ring and ball temperature rheological test (Isochron 10 Hz; See Figure 1) • Determination of Aggregate Size Distribution To evaluate the impact of the manufacturing temperature on the asphalt, we took a mix sample just after production in the plant and on site after two hours. We compared the characteristics of these asphalt samples to those of the asphalt after the Rolling Thin Film Oven Test
Table 1. Evolution of the Void Content During Compaction TIME
temp inside layer
number passes
% voids*
To: 9h20m
115oC
0
21.9
To+7m: 9h27m
113 C
4
12.6
To+16m: 9h36m
109oC
8
9.1
To+30m: 9h50m
89oC
12
6.4
*read by nuclear gauge
o
The WMA flows from the drum to the conveyor. www.theasphaltpro.com | ASPHALT PRO 39
The team followed a truck from loadout, with mix temp of 122oC, to arrival 90 minutes later.
The Evotherm DAT H5 warm-mix process is based on the addition of a chemical package in an aqueous phase. The mix tech merely makes an aqueous solution with between 10 to 15 percent in weight of additive.
(RTFOT). We performed void content, dynamic modulus and indirect tensile strength tests to determine mechanical properties and found that the grading curves of the aggregates after asphalt extraction were in conformity with the mix design reference. We thought that the difference in temperature would show us a difference of oxidation of the binder because this phenomenon has been observed before. But the data collected for this project show similar values and similar rheological behavior between the two binders extracted from the WMA and HMA control. Penetration values tend to show maybe a softer binder (less oxidized) from the WMA core samples.
We estimated a fuel savings on this project of about 34.5 percent. Nevertheless, data show a similar mechanical behavior of the two mixes, but with 50-degree C difference application. Modulus and indirect tensile strength of the Evotherm WMA are equivalent to the HMA control. The values found on samples taken from the jobsite also corroborate the ones found during the lab study previously carried out for the validation of the mix design. For years now, EUROVIA and MeadWestvaco have worked together to develop Evotherm in France and Europe, with more than 1 million tonnes of Evotherm mixes applied. Confidence in WMA grows and large projects, such as the motorway project discussed here, can now use the technique. Energy-related and environmental pressures ensure the use of warm technologies and their flexible, quality performances will continue. 40 February 2012
By sinking a thermocouple into the mat about 5 cm (2 inches) from the top, researchers discovered the temperature decreased about 1 degree C per minute.
Pennsylvania’s McCormick Hosts Senator by AsphaltPro Staff
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sphalt professionals in Pennsylvania don’t let their representatives forget the issues that affect the nation’s infrastructure. President Owen McCormick of Joseph McCormick Construction Co., Inc., Erie, hosted an industry fundraiser at his home for Sen. Pat Toomey (R-Pa.) Jan. 11, where attendees could discuss the highway reauthorization bill. Another topic around the table was the need for early action on a multi-year highway bill when the Senate got back to business in late January. “My wife Kim put on a beautiful luncheon at our home,” McCormick said, “that gave us a chance to spend some time with the senator and share the issues that affect our industry.” Among his other responsibilities, Toomey serves on the Budget Committee and the Commerce, Science and Transportation Committee. The National Asphalt Pavement Association (NAPA), Pennsylvania Asphalt Pavement Association (PAPA) and others participated in the event. NAPA Executive Vice President Jay Hansen reminds professionals that any member interested in hosting a similar event should contact NAPA at (888) 468-6499 for assistance and possible support.
From left, Owen McCormick and Sen. Pat Toomey visit during an industry fundraiser in January.
Brown Accepts NCAT Hat by AsphaltPro Staff
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Dr. Ray Brown Director Emeritus, NCAT 42 February 2012
n time to help plan the National Center for Asphalt and Technology’s (NCAT) 25th anniversary celebration in the fall, Dr. Ray Brown returned to the center as director emeritus. He served as director for 20 years, leading the center to a number of major accomplishments and developments within the asphalt paving industry. After working as a Department of Defense pavement expert with the U.S. Army Corps of Engineers since his retirement from NCAT in 2007, Brown returns to NCAT where he works in his areas of special interest: asphalt materials, mix design and construction. Given his knowledge of industry and its players, he’s been a help planning and organizing outreach projects, and he’s traveled and presented at various conferences on behalf of NCAT since his return. As if all that wasn’t enough for a part-time position, his colleagues list one of the most important services Brown performs. “He also acts as a mentor to our engineers, especially new ones, and even to our visiting scholars and grad students, offering guidance on their respective research projects.” For the asphalt research community, it’s a joy to welcome Brown back to NCAT. For more about Brown, check out the feature article at www.theasphaltpro.com.
Plan for Plant Moving Costs by Sandy Lender
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mong the benefits of a portable asphalt operation, you may find extra costs lurking in the shadows. Let’s get a handle on some of those hidden costs of portability. A set of experts weighed in on a host of items such as wear part weight, crew familiarity, component age, ancillary equipment and a whole lot more that can help keep you in the black. “The single biggest suggestion I can make is to spec wear parts according to wear life, not weight,” Brian Handshoe of Kenco Engineering recommended. He sees the opposite too often. When a plant owner opts to purchase a lower-weight part for traveling ease, it’s likeA slat conveyor often gets abused during transport of a portable plant. Thick wear parts of ¾-inch pictured here make sense for production and for transport, yet weigh ly to wear faster and need replacing sooner. more than thin, more fragile slats of 3/8-inch. An owner has to make a decision wheth“Consequently, they spend a lot of extra time er to pay extra in dismantling costs when he moves the plant with thicker slats or and money regularly replacing products that to pay extra in replacement costs when thinner slats could break during moves and could go much longer if they chose higher wear out faster during production. Photo courtesy of Kenco Engineering. quality wear materials,” Handshoe said. The example Handshoe offered is of a “If there’s residual material in the AC tank, caked dust in customer up north that we will not name. “One customer the baghouse, material build-up in the drum or SEB, some has been quoted Kenco ‘Alloy-K700’ lifter flights numerof these loads can easily become so overweight that states ous times because our sample has gone about four to five won’t allow them to be moved without removing compotimes longer than the standard OEM flight, and is still going nents to lighten them,” Orahood said. strong. A good maintenance regimen will help get that kind of “Unfortunately, our flights would add about 1,500 to weight out of the system. As Handshoe mentioned above, 2,000 pounds to the total drum weight,” Handshoe continthe drum can get heavy with good maintenance. ued. “They insist that their drum is already so heavy they “Most portable drum mixers are made out of 3/8-inch can’t add any more weight. Consequently, they continue steel,” Orahood said. “Some of the older ones may have replacing flights every year or so and continue to lose veilhad their shell replaced at some point with a ¾-inch steel ing efficiency at the end of their flights’ lifecycle. That costs to add to the longevity of the drum. This almost always them a lot of money. They would rather deal with that, howmakes the drum overweight, and is impossible to tell withever, than chip out the build-up in the mixing section or add out taking drum shell thickness prior to moving. Sometimes, a set of axles to the trailer.” we can’t even tell what the weights are until we pull over a Something else you can run into with thinner, thus lighter scale, at which point you can account for fines and emerparts is breakage. Handshoe has seen this as well. gency service crew travel to remove components to lower “I was recently speaking to a customer who was experithe weights.” encing breakage on slat floor wear plates. His portable plant Bill Garrett of Meeker Equipment suggested having such came with 3/8-inch thick wear plates in order to keep weight an emergency crew travel with the plant. Orahood can recto a minimum. These plates, however, tend to break due to ommend a producer shave costs by keeping a stable crew the inherent flexing that a portable slat conveyor experiencall along. es as it rolls down a potentially bumpy highway. Our ¾-inch “If a contractor has a crew in place to run a portable plant thick plates would hold up much better in this application, and dedicated to moving it, the crew is usually very familiar but would weigh substantially more.” with the equipment and can plan ahead, absorb repair costs. The moral of the story is not to skimp on wear parts. Yet Sometimes they own their own trucks, etc. New plant manuyou’ve got to get the plant from point A to point B. That facturers will claim it should cost $50,000 or less to dismanwill mean reducing weight (removing items) before the plant tle, ship and re-erect a 400-TPH portable plant, but in realpart in question gets to the scale. ity that’s a brand new plant being moved a short distance.” Josh Orahood, regional sales manager for Reliable AsWhat Orahood often sees is an older plant that has been phalt Products, discussed shipping weights and the costs sitting for some time; hydraulic cylinders in the self-erecting involved in reducing weight. 44 February 2012
silos have become pitted from bad weather and tires have decayed from non-use in dusty, dry conditions. Other hidden costs mount depending on circumstances. He said, “Lesson one about a portable plant is that it should be moved every six months to truly maintain its portability.” Do you recognize any of these conditions in your operation? “Not all portable silos are self-erecting,” Orahood reminded readers. “Some of the older, larger ones will require a crane to erect. Some are only equipped with axles and were never meant to be self-erecting. Even a true self-erecting silo is not always ‘self-erect’ as the hydraulic cylinders that erect them can become pitted or otherwise damaged through misuse or weather; winch systems can become damaged as well. Costs to repair these systems can outweigh a crane cost. “Erection costs for a standard 200-ton silo with single drag slat can cost around $12,000 in ideal conditions—labor and cranes,” Orahood continued. “Keep in mind, now you will need to pour a foundation for a scale, unless you have a reverse weigh silo, which is rare. The costs for concrete could range from $10,000 to $40,000 in addition to the cost of an actual scale. Also, it doesn’t make a lot of sense to only put up one silo, so tack on another $8 to $10,000 for the second one, plus additional freight from point A to point B for the silo, miscellaneous loads, etc. Freight costs are hard to put a number on because of the variances in fuel, distances traveled, load dimensions, etc., but a typical silo moved within the same state should be around $2,500 plus all of the ancillary legs, scale, transfers, etc.” Don’t forget the repair needs that pop up. “Costs to repair an SEB that has been damaged and weathered could get into the $20,000 to $40,000 range if the work is to be outsourced. If the equipment is left in the weather and not regularly maintained or protected, those costs could apply every time the SEB is moved. This is usually not the case, but that’s why these costs are ‘hidden,’ right?” Another hidden cost Orahood pointed out attacks one side of your plant more than another. Providing shade for exposed, tender points might make a good savings plan. Here’s why. “If the plant hasn’t been moved recently, or if the tires and axles haven’t been protected, the tires will likely begin to decay, brakes will seize, air lines will decay and rot, etc.,” Orahood warned. “Generally, if a plant hasn’t been moved within the last couple years and the running gear has been left in the weather, $2,500 per axle to replace tires, fix brakes, etc., should be accounted for. There are so many variables in this though, that the number is just a ballpark. “The sunny side of a plant usually goes first. Rubber on plants out west generally goes faster than on plants in the less arid climates. We (Reliable Asphalt) moved a baghouse once for Rogers Group on a late model portable plant that hadn’t been moved within three years. The tires looked pretty good, so we started moving it. From Florida to northern Alabama it cost us $34,000 in emergency repairs from tires blowing on the sunny side of the baghouse. The cus-
tomer paid for the plant to be delivered to them so we had to absorb those costs and learned our lesson. Replacing all of the tires and having an actual tire shop come check and repair all of the axles could cost $50,000 or more, but two bad loads could overshadow that cost in one move. Again, distance and condition are considerations.” Not only big, noticeable components suffer when a portable plant sits for an extended time. Watch for surprise costs in the wiring department. “If the plant has been sitting, the wiring will rot,” Orahood said. “If the wiring is buried, it’s virtually unsalvageable….It could take days or weeks to locate the source of the problem and remedy it, costing $1,000 per day or more for a master electrician to troubleshoot the problem….Unless the wiring looks fresh and new, just replace it. A complete plant rewire can get into the $200,000 range very easily, depending on labor costs, plant location, etc. “Portable plants are built with quick disconnect plugs, which are easily unhooked and then replaced when moving a plant. But if these are damaged by service crews that aren’t electricians, those can easily cost $2 to $5,000 to repair or replace, depending on the size and the labor costs involved. Most mechanical crews won’t touch electrical and vice versa.” Frequency of moves makes the portable plant worth the time and energy, and keeps its portability feasible. Garrett offered not just reassurance for the portable plant owner, but also provided a great list of hidden costs to plan for when you’ve got a portable plant in your operation. (See Sidebar Below.) “If you need a portable because you move several times per year to the various job sites, then…the costs associated with the portable plant allow you to complete the work you have bid,” Garrett said. “Without the portable plant on the job site, you couldn’t complete the job. The extra cost of the portable is less expensive than trucking material from a stationary plant to a remote location.”
Bill Garrett’s List of Hidden Costs
• paying for out-of-town labor/expenses • permitting each location • job delays/fines if you don’t adhere to all local codes for the site prior to move-in • prep of plant sites—loader ramps, paving stockpile area • cribbing materials to meet site conditions • Johnny-on-the-Spot toilets • potable water, water for WMA • generator • security lighting; good locks on AC, fuel tank valves • asphalt calibration expenses • typically horizontal asphalt tanks, heating efficiency issues • shutdown before move requires complete use of all asphalt—you can’t move a tank with AC in it • a parts/shop/tool van must accompany the plant on the road • safety—electrical & piping, access platforms to replace, AC tank unloading areas • employee salaries to keep stable crew during moves • possibly a ground person with a skid loader?
www.theasphaltpro.com | ASPHALT PRO 45
Preview Asphalt, Aggregate Advances of the World
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his year’s co-located World of Asphalt (WOA) and AGG1 Aggregates Forum & Expo (AGG1) tout the theme of “Position Yourself for Growth.” That means asphalt and aggregate industry professionals attending the March 13 through 15, 2012, event at the Charlotte Convention Center in Charlotte, N.C., USA, will be privy to the leading advances in the combined industry. In a departure from past show previews, we’re not going to print a bunch of pages of exhibitors’ equipment that may or may not be on display at the show; we’re going to forecast some of the technological breakthroughs that will place WOA attendees ahead of the competition who stayed home. You can begin that education on page 12 with WOA speaker T.J. Young’s interview “Here’s How to Adjust Dryer Flights.” We’ll continue right here with the most important area of business for any company: safety.
48 February 2012
Safety
by Sandy Lender
At the 57th annual meeting of the National Asphalt Pavement Association (NAPA) in Palm Desert, Calif., speakers Tony Bodway of Payne & Dolan and Mike Seymour of the OSHA Directorate of Standards and Guidance presented an update on the new OSHA silica standard that our industry has proactively studied. As many readers know, original equipment manufacturers (OEMs) of milling machines/cold planers seek more ways to keep silica dust, which has been named a hazardous substance, away from workers during recycling operations. Bodway explained to the audience that silica dust can’t be effectively controlled by a water spray system alone, which is what industry has relied on in the past. He shared that after working together to test, re-test and share ideas, industry believes a Vacuum Cutting System (VCS) may be the right tool to enhance silica suppression.
Safety Edge States 1. Delaware 2. Illinois 3. Iowa
4. Minnesota 5. New York 6. Oklahoma
7. South Carolina 8. Tennessee 9. West Virginia
NIOSH personnel tested the VCS with tracer gas. Bodway explained that personnel pumped smoke under a cover that surrounded the milling machine being tested. The smoke showed areas that were leaking, which allowed the personnel to go through and plug the leaks. Then they pumped in the purple tracer gas to watch for results. Bodway referred to this as “a tedious operation.” So far, he reported, Wirtgen (booth #639) and Terex (booth #2265) have completed their tracer gas tests. Cat (booth #1020) is to have its tracer gas test “soon” and Roadtec (booth #1221) is scheduled to have its test done during the first week of April. Volvo (booth #1205) is still in the water testing stage with its miller. What does this mean for the asphalt and recycling industry? It means the five OEMs listed above have worked with safety organizations to prepare for the proposed ruling on silica dust handling. Seymour shared that NAPA providing evidence from the tests already run puts the asphalt industry in a powerful position for making suggestions on rulings. The current proposed rule package was submitted to OMB
Illustration courtesy of TransTech Systems, Inc., Schenectady, N.Y.
February 2011 and will be published in the Federal Register when OMB gives its approval. To see the continuous water spray systems and learn more about the VCS on milling machines, visit the OEMs mentioned here. Worker safety isn’t all you can check on at the show. The importance of a safe pavement edge for motorists is gaining momentum. At press time, nine states require a sloped shoulder to make the pavement edge safer for drivers who
www.theasphaltpro.com | ASPHALT PRO 49
The new Tier 4i tracked paver from Roadtec features increased fuel capacity and a spot at the booth #1221 display. Photo courtesy of Roadtec, Chattanooga.
run off the road and make a quick correction to get back on (See sidebar “Safety Edge States”). Several OEMs will have sloped edge making devices on display, including Advant-Edge Paving Equipment (booth #2317). Gary Mittleman said his company’s Advant-Edger™ 50 February 2012
has a patent-pending replaceable shoe and a reversible feature. The item is designed so asphalt can’t get behind the device and move it out of place, yet the crew can adjust the angle of the edge anywhere from 5 to 40 degrees. TransTech Systems, Inc., (booth #712) makes the shoulder wedge maker, shown in the illustration on page 49 TransTech researchers worked directly with FHWA personnel about three years ago to engineer this original device and the company’s president has seen a variety of state specs to achieve the safe slopes that FHWA suggests. “Some states simply ask the contractor to produce a specification to achieve the edge and others are very specific about using a specific device to achieve the edge,” David Apkarian said. “There will be a Safety Edge Design and Construction Guide published by FHWA that provides recommendations. It’s in draft form currently.” The folks at Carlson Paving (booth #1139) will show off the Superior Safety Edge Bevel. This is a beveled end gate, which Tom Travers of Carlson explained uses electric heat and angle of attack to obtain a heated, screeded, compacted and sealed sloped edge. Troxler and Willow Designs also make sloped edge devices, but neither responded to questions about them.
Tractor Tech
To make the sloped edge discussed above, the screed gets all the attention. For a few OEMs at the show, the back end of the tractor steals the spotlight for other reasons. Bill Rieken of Terex Roadbuilding talked about the new CR652RX paver the company will have at booth #2265 and focused on its ability to spread mix without centerline segregation. The folks at Dynapac (booth #1739) have a patent on one way to get the center drive box out of the way so the screed gets an uninterrupted spread of mix from the head of material, but Terex has come up with a way to fix that center-box problem, too. Rieken said the industry uses baffles and turns the middle augers around and introduces material to the crown, which adds stress to a 1-inch screed plate. “We eliminated all that with the outboard drive set-up,” he said. “We used the independent drive communication system of the remix paver to retain the uniform spreading RPM.” Check out Figure 2 on page 48 to see what he’s talking about. The two conveying augers in the bed of the hopper move mix to the back and under the operator’s station of the paver, feeding the mix to the spreading augers. The two sets of augers match in RPM so you see the spreading auger turning all the time with the half head of material that feeds the screed. Rieken also pointed out that the CR652RX has the company’s patented screed assist, which allows the operator optimum screed ground pressure. The ground pressure varies
Even with the VR 600-2 screed set to its maximum width of 28 feet, the three-section telescoping tube that allows the infinitely variable width control remains rigid and robust for optimum stability and strength, according to Vögele. At maximum width, each tube section is extended by no more than half. The 3-point suspension prevents the extensions from jamming or pinching. The telescoping tubes are positioned at the top of the screed to avoid any contact with the mix. Vögele reps say the deep screed plate design provides excellent floatation. Photo courtesy of Wirtgen America, Antioch, Tenn.
www.theasphaltpro.com | ASPHALT PRO 51
In this single drum design from Asphalt Drum Mixers, aggregates enter the drum on the opposite end of the burner, drying as it travels from its entry point to the burner. It then passes behind the extended burner nose into an expanded drum section where the liquid AC, baghouse fines and recycle are introduced. These materials continue through a generous mixing zone and discharge into a drag conveyor. The new EX Series from ADM is designed for easy transport and set-up along with other advantages inherent to the counterflow design. Photo courtesy of ADM, Huntertown, Ind.
Released in January, the PMIII plant control system from Astec Controls features a streamlined user interface. It was designed with minimal graphics on each screen, but with the ability to get at more information. In this way, PMIII makes abundant information available as you need it without overcrowding each screen. The program features built-in diagnostics as well to help operators identify the source of any plant problems. Photo courtesy of Astec Industries, Inc., Chattanooga.
with width and mix design so this minimizes screed settling; that means no transverse bump to mess with your IRI. Another innovative material handling system comes out of Caterpillar Paving Products; the Ratio Control Dial allows the paver to automatically maintain a laydown rate of material if the paver changes speed. Jon Sjoblad with Cat (booth #1020) said the company will display its AP1000E paver with AS3301C Extend-aMat screed and AP555E paver with AS2252C Vers-a-Mat screed. Both will have Cat Grade and Slope installed and independent control of conveyors and augers. He pointed out that the AS3301C is their newest for the North American market. It features CANbus control, standard electronic heat and a few other conveniences to check out at the show. 52 February 2012
Cat also has a C7.1 Tier 4 Interim, 225-horsepower engine in the new pavers Roadtec (booth #1221) will have on display. Both of Roadtec’s 10-foot standard asphalt paver models have gotten a major redesign, which includes Tier 4i emission technology. The RP-190e is a rubber-tired highway class paver; the RP-195e is a tracked highway class paver. (Models that are sold into certain export markets without Tier 4i standards will carry the designation “ex” behind the model number.) The pavers have redesigned hydraulic tunnel panels for improved accessibility and increased fuel capacity from 120 gallons to 135 gallons. The conveyor chains have been beefed up and the tough floor plates are made from wear-resistant chromium carbide; they drop in without bolts. Vögele also brings a relatively new screed to the show. The VR 600-2 is designed specifically for the range of Vision pavers. The new rear-mount extending screed is equipped with vibration across the full paving width, which is up to 28 feet. A single-tube telescoping system allows infinitely variable screed width control that you’ve got to stop by booth #639 to check out. Extension and retraction of the screed is controlled through Vögele’s ErgoPlus operating system via two fixed consoles on the main screed and two remote control units.
#1545, but ADM reps will have pictures like the one shown at left to help describe the product. Astec (booth #1427) brings new technology to the plant world as well. In addition to the new V flights the company recently announced, reps will be happy to discuss two new products from Astec Controls. PMIII is a new PLC-based control system comprised of individual modules for burners, silos, motor controls, and blending and loadout. The modules can be installed together as a package or individually. The new Data Acquisition System Hub (DASH) provides a real-time snapshot of operations. DASH gathers information
Plant Growth
While the paving equipment OEMs have great advances for you to check into, no issue of AsphaltPro is complete without a look at the new tech for asphalt plants. The folks at Asphalt Drum Mixers (ADM) stepped up to the plate in a big way for you in 2012 with the launch of a new drum. The new EX series enhances the counter-flow plant market with a drum that’s expanded at the discharge end to provide a larger mixing section. ADM offers the drums in 140 to 350 TPH production rates. The EX uses either a Starjet or an Ecostar Hauck burner. ADM’s Steve Shawd explained, “Its nose extends roughly a third of the way into the drum. By extending the burner into the drum, it allows the mixing process to take place out of the process air stream—behind the burner.” Shawd said the new EX series offers the same advantages that the MileMaker does—higher RAP percentages, higher efficiency—but in a more compact package. The actual drum is too large to display in the ADM booth www.theasphaltpro.com | ASPHALT PRO 53
from multiple plants and makes it accessible via web browser or flash-compatible devices. With DASH installed, managers can analyze trends throughout an operation and make decisions. DASH is compatible with Astec control systems TCII, PMII and PMIII. Don’t count Dillman out when you’re checking on new info. The company introduces the portable, 200-TPH Dillman Voyager plant. Reps assure producers Dillman has kept the design simple and the price affordable by using field-tested components. The new plant is built around the Dillman unified drum and includes a 50-ton SEB to ensure a quick set-up without the need for cranes. It comes with a Whisper Jet 50 burner, a 34,000 cfm pulse jet baghouse, and the PMII control system from Astec. In place of the 50-ton SEB, customers can choose a 100-ton craneerect silo. A four-bin cold feed is standard with the option of adding more bins. A recycle system is also optional. Of course a whole portable plant won’t fit in booth #1427, but Dillman reps will be pleased to discuss the new Voyager and its five-day dismantle-to-production moves. No asphalt show is over until you’ve checked into the WMA updates. Did you know the Illinois DOT is specifying WMA as a preference for 2012 overlays? From sessions such as “Lower Your Costs and Be Green” and “Warm Mix Asphalt by Foaming” and “Warm Mix Asphalt by Additives” in the education section to more than a dozen OEMs on the show floor with WMA equipment technol-
ogy (at press time), you’ll find a way to join the evolution of asphalt mix wherever you turn. Some of the WMA additive suppliers weighed in with advances they can share with you on the tradeshow floor. For instance, a Missouri contractor complained of a mix with recycled asphalt shingles (RAS) in it stiffening up too much during a long haul. Ed Myszak of PQ Corporation (booth #2144) suggested a warm-mix additive can keep that hardening of the mix at bay while replacing sand in the RAS stockpile. “Advera WMA can also be added to the shingles either before or after grinding to act as a flow aid to the ground up shingles,” Myszak said. “The Advera prevents the shingle pile from agglomerating into a mass that’s difficult to impossible to break up, particularly during summer months. It will also provide WMA characteristics to the asphalt mix produced with this material.” See Figure 1 on page 50 for another application of a WMA additive to smooth out a sticky RAS mix. In that case, MWV Specialty Chemicals (booth #1500) came to the rescue. That’s environmentally friendly on a couple of levels. Heather Dolan of MWV said, “Using Evotherm WMA to leave fibers out of SMA and OGFC mixes saves money through labor, material and energy savings.” The planet savings start further back in the process. “Evotherm additives are derived from by-products of pine tree processing for the paper industry, where noncellulose waste is typically burned as a waste fuel,” Dolan said. “Instead of burning these materials, they are recovered, refined and processed into Evotherm. Evotherm chemistry is 45 to 55 percent derived from these renewable waste streams.”
Get Educated
No matter what aspect of the industry you’re most interested in, the exhibitors are poised to get your attention. Even at the AsphaltPro Magazine booth #2310 we have a fabulous firearm you can win in our Amazing Road Race. Check out pages 58 and 59 in this issue for the awesome details. Stop by to visit with us at the show and to pick up your ticket for the race and after-party. Check the handy show guide when you arrive or visit the website at www.worldofasphalt.com to “plan” your show ahead of time so you get to all the booths you want to visit. Don’t forget the education sessions are designed to teach you best practices in whatever area you feel weakest. Jump in there and get up to speed. The savvy contractor can take care of two tasks at once with the conference. We confirmed that if you sign up your paving crew for the “People, Plants and Paving Training Program” at WOA, you can use that time toward your NAPA Diamond Paving Commendation in 2012. It may sound a little corny, but there’s something for everyone in the larger asphalt and aggregates industry at WOA and AGG1. The technologies discussed here are just the tip of the iceberg. We look forward to seeing you in Charlotte. 54 February 2012
International Precision Work
by AsphaltPro Staff
I
n the Saitama Prefecture, Japan, the Nippo Corporation paved the access roads to a car maker’s new research and development plant. The crew used the Sakai GW750 and TZ701 to achieve compaction, even on a challenging base layer. Also notice the doubledrum, walk-behind roller the Nippo worker uses to get precision compaction alongside curbs, drains and other delicate features of the roadway. This HV60ST is most often used in static mode, but the manufacturer stated the worker uses it in vibratory mode on uneven areas. Photos courtesy of Sakai America, Adairsville, Ga. 56 February 2012
Palm Beach Floats AggregateProduction by Carl Emigh
P
alm Beach Aggregates, Inc., located on 4,400 acres in western Palm Beach County, Fla., more than doubled its quarry base rock production while cutting operating costs. It took innovative thinking from Operations Manager John W. Bates and some custom designing from Grasan, Galion, Ohio. They came up with a 3,000 ton-perhour, tracked impact crusher plant that feeds a 2,000-foot floating, moveable conveyor beltline. Palm Beach operators move the floating beltline periodically with four 20-horsepower outboard motors and can connect it to four land-based beltlines that transport crushed materials to the company’s 58 February 2012
stationary processing (final crushing/screening) plant.
Out with the old
The quarry was opened in 1993 and purchased by Palm Beach Aggregates in 1997. That’s when Bates came on board and inherited a system that employed a stationary processing plant with a primary 500-tph impactor with secondary/tertiary impact crushing and screening for producing aggregate products. Back then the operation also had a portable 500-tph primary impactor crushing base rock in a pumpeddry pit. This is one of only several areas in Florida where the pit can be pumped dry and kept dry due to the impervious rock formation.
First, the crew would strip off the overburden—8 to 10 feet—with an excavator and sell it as structural fill. (As a side note, they still do this with the new system.) Under the overburden are two 9- to 10foot layers of lime rock. The upper layer is a coral limestone that Palm Beach workers call gold rock. The top of the gold rock layer is 1 to 2 feet above the natural water table. The bottom layer is limestone with a high seashell content that Palm Beach workers call gray rock. With the old system, a front-end loader scooped up gold rock, and someone trucked it to the stationary plant to be processed and sold for use in making asphalt and concrete. The crew crushed the gray rock to 3-inch minus in the pit for
The crushing plant feeds a 2,000foot floating beltline that can connect to four land-based conveyor beltlines that lead to a stationary crushing and screening plant where up to 14 finished products are produced.
use as road base and then loaded it into customers’ trucks in the pit. As each new pit was mined, the water was pumped out to an old pit with two 12-inch pumps. “That system was much too slow, burdensome and expensive,” John Bates said. “In this tough, competitive business, you have to keep finding ways to cut costs and improve production efficiency. “We were using about 6,000 gallons of diesel fuel per day to operate the crusher, seven haul trucks, two loaders, a bull dozer, a grader and two water trucks….We had high maintenance costs and shutdowns that occurred far too often. We simply had too many problems and too much expense.”
In with the new
“In 2005 we started switching to the new system,” Bates said. “The first step was adding an efficient, high capacity dragline. I thought it would be more efficient to harvest and crush the gold and gray rock together, rather than separately, and not have to pump the pit dry. We were able to locate a 1973 Bucyrus Erie 1260W, which we bought and had refurbished, including the addition of a PLC controller. It would have cost twice as much for a new dragline, plus a 3½ year wait. “We also went green. Now everything is electric except the grader, dozer and water trucks,” Bates continued. “We’re down to using 1,000 to 1,500 gallons of diesel fuel per day, which is a major cost reduction and much better for the environment by leaving a smaller carbon footprint. “To increase our production efficiency and capacity, I saw basically two choices,” Bates said. “I would need two large crushing plants or one gigantic crushing plant. I figured one plant would take half the maintenance time, half the parts to stock, less crew personnel time and a lot fewer headaches overall. But it would have to be like no crushing plant I had ever seen before.”
cal system; everything in the pit is 4160.” Not every portable crushing OEM will have all those specs on a machine on hand, ready to take on wet, sticky material like the material Palm Beach crews deal with. Bates got some good recommendations for Grasan and decided to have the Ohio company custom-build the “gigantic” plant. “The crushing plant was designed and built from scratch by Grasan, working very closely with us all the way,” Bates said. “The Grasan engineering people were great to work with, and we developed a very close-knit relationship as the plant underwent several design changes over a period of time. The finished machine is precisely what we need and want for our operation and is performing as planned. Grasan provided us with a custom-written continued on page 62
John’s Wish List
“I started putting together a list of what I would need in such a machine,” Bates said. “I wanted a New Holland type impact crusher with a large upper cavity…An impactor is best for our gold and gray limestone, helping us meet LA abrasion specs for hardness. And the impactor explodes the softer materials into sand and reduces shells to 1/8inch material. “I wanted 3,000 tons-per-hour crushing capability, and I wanted the crushing plant track-mounted to propel at various angles up to 90 degrees. I wanted a scalping screen and an apron feeder that would accommodate a very high volume of incoming material. And the plant had to have a 4,160-volt electri-
Palm Beach Aggregates Operations Manager John W. Bates came up with the design concept for the tracked crusher, power shovel, dragline and beltline system combination. www.theasphaltpro.com | ASPHALT PRO 59
Attending The World Of Asphalt This Year? Don’t miss the fun! Visit Booth #2310 to enter the Amazing Road-Race and be entered in the raffle.
One lucky winner will receive this year’s GRAND PRIZE:
Mid-length Moe AR-15.
“Mid Length Moe” featuring: 16” Cold Hammer Forged Government Profile Barrel 5.56 x 45 NATO Chamber Magpul MOE Furniture Set
Racers, Start your Engines!
Visit the Asphalt Pro booth (#2310) to register and receive your race card.
Burn some rubber
Head out onto the show floor with your race map and list of participating exhibitors.
Make regular pit stops
Make sure to visit each participating exhibitor’s booth, complete the race question, and get your card stamped.
Join the Winner’s Circle
Join fellow road-racers and sponsors for a post-race celebration and drawing. Grand Prize: Mid-length Moe AR-15 machine gun from CMMG, Inc.
SPONSORS
The heart of the Palm Beach Aggregates quarry is a custom-designed 3,000-tph impact crusher, refurbished 1976 Marion M191M power shovel with 25-yard bucket, and a floating, moveable conveyor beltline that can connect with four land-based conveyor lines. The crushing plant is 47 feet high, 39 feet wide, 122 feet long (183 feet with discharge conveyor) and weights 1.2 million pounds. It’s mounted on two sets of custom-designed tracks with self-leveling stabilizer legs and can travel at ½ mph. It can turn at various angles up to 90 degrees.
continued from page 59
operation and maintenance manual, as well as training for our personnel. Operation of the plant is pretty simple, really.” The plant measures 47-feet high, 39-feet wide and 122-feet long. That stretches to 183-feet long with the discharge conveyor. It weighs 1.2 million pounds and produces up to 3,000 tph of crushed material. A 60-inch by 75-foot discharge conveyor deposits crushed material directly into a wheeled, rolling hopper on a 2,000-foot floating conveyor beltline mounted on pontoons. The floating beltline can connect with four land-based conveyor beltlines leading to the stationary final processing plant, which can produce 62 February 2012
up to 14 different materials, depending on demand. The screening equipment can produce eight materials simultaneously, including drain field, road base and various aggregates for production of asphalt and concrete. Virtually all the materials are sold to construction trades in the local market. Palm Beach operators have run more than 5.5 million tons through the plant and work diligently to keep everything in good shape for that kind of throughput. “The plant runs extremely well and is very dependable,” Bates said. “We devote two days a week to maintenance, at which time we do a thorough inspection of the crushing plant for wear and perform all required maintenance procedures. The
crusher is equipped with four square manganese blow bars. Every two or three shifts we weld the bars to build them up as needed, depending on the wear patterns. Overall, maintaining the machine is pretty simple.”
Use it Like This
Maintenance keeps the machine in good shape, but there’s more to getting the full benefit of a crusher than keeping it in good repair. Bates said that his crew knew they’d have to feed the crusher efficiently and continuously if they wanted to realize its 3,000-tph capability. “After a thorough search, we located a 1976 M191 Marion power shovel in Montana,” Bates said. “We bought it, took it apart, had
it shipped to our quarry, and had it completely refurbished, including adding a PLC controller. It’s the only shovel of its kind operating in Florida, and maybe the only one in North America. We could have bought a new 20- to 25-yard machine, but I wanted the older, strip-mine type with longer reach so we could feed the crusher better and not have to move it as often. “The company owners have nicknamed the power shovel ‘Little John’ and the dragline ‘Big John’,” Bates chuckled. “They both keep the Grasan crusher and our whole quarry system humming.” Bates has the quarry operation set up so there is little or no equipment idle time. The dragline and crushing plant operate in coordination with each other at opposite ends of the pit. At one end the dragline scoops up gold and gray rock together and 64 February 2012
accumulates a long, high stockpile to be crushed later. At the other end of the pit, the crusher processes material that had been brought up earlier with the dragline and, thus, has had some time to dry. “We move the crusher a short distance once each day to keep up with the diminishing material stockpile,” Bates explained. “When the stockpile is gone, we switch the dragline and the shovel-crusher combination to their opposite sides of the pit. We move the floating beltline at the same time with four 20-horsepower outboard motors. It’s the only conveyor line I know of that has life jackets on it,” Bates said, grinning. “The whole beltline and equipment moving procedure can be completed in one 12-hour shift. “This type of operation with the dragline-shovel-crusher combination and beltline system has more than
doubled our production capabilities and reduced costs dramatically. “In addition, mined-out pits have not gone to waste, but rather are being used for fresh water storage,” Bates emphasized. “Pits are 27- to 30-feet deep when all the rock has been removed. Using a dredge, we have deepened a 900-acre previously mined area to 57 feet, developed it for water storage and sold it to the South Florida Water Management District as a pre-built reservoir. Demand for fresh water in Florida keeps growing and growing, and we hope to develop more reservoirs with our mined pits in the future. “We currently have reserves in our quarry for at least 20 more years of production. With proper maintenance and care, I believe our whole system will still be going strong all the way—and then some.”
Wooten Wins Top Honor by AsphaltPro Staff
T
he S.T. Wooten Corporation, headquartered in Wilson, N.C., paved its fair share of asphalt roads in 2011. One of those projects was so well planned, so well executed and so well received that it not only garnered a Quality in Construction award at the 57th annual meeting of the National Asphalt Pavement Association (NAPA) in Palm Desert, Calif., Jan. 25, but it also received the Sheldon G. Hayes Award. The North Carolina Department of Transportation owned the I-795 project in Wayne and Wilson Counties. The AsphaltPro staff also congratulates the two finalists in the Sheldon G. Hayes competition. Norris Asphalt Paving Co., Ottumwa, Iowa, won a QIC award for its Iowa DOT project on U.S. 63 in Mahaska County. Northeast Asphalt Inc., Greenville, Wis., won a QIC award for its Wisconsin DOT project on U.S. Highway 45 from Eagle River to Land O’Lakes.
The proud team from S.T. Wooten Corp., Wilson, N.C., displays its hard-earned Sheldon G. Hayes Award at the NAPA 57th annual meeting awards ceremony.
www.theasphaltpro.com | ASPHALT PRO 65
equipment gallery
Get in the Zone by Jennifer McNally
Editor’s Note: As we take a look at automation and technology in the lab and in the field this month, the Equipment Gallery department highlights some names that might be new to asphalt professionals. Inthinc Technology Solutions, Salt Lake City, offers a fleet management program here, and also offers a safety product in our Safety Spotlight on page 8.
W
hen a big project requires a fleet of trucks be sent out to a rural area, management relies on trust to get the job done right. You may have the GPS equipment to assist in monitoring, but the job could be off the electronic grid. You’ll have to trust that drivers know what’s expected of them and will follow the rules for their safety and that of the motoring public. It might be time to get smart—or at least get smartZones, a new software program enabling fleet managers to assign specific attributes within a zone they create. The attributes that the fleet manager inputs map the company’s safety policy including speed limits, seat belt use and aggressive driving protocol. The software was created through inthinc Technology Solutions, a company focused on improving driver safety and fleet management. To use smartZones, a vehicle must first be equipped with inthinc’s basic technology. From there, a variety of programs and functions may be added. “Speed-by-Street” software, for example, has a database of speed limit regulations for roads and highways across the United States, and as the name suggests, monitors driver speeds in comparison to those limits. When using the smartZone technology, company management is able to use an online map and create a geo-fence around a defined area, and then set specific attributes for employee behavior within that zone such as arrival and departure
The fleet manager can draw or create a zone of whatever shape or size is necessary for the geo-fence boundary with the smartZones software. From the comfort of his office, the fleet manager monitors smartZone activity via the web-based inthinc management portal; data is transmitted wirelessly in real time. 66 February 2012
times. The service also provides fleet managers with regional or individual scorecards, in-cab verbal coaching for drivers, GPS and trip reporting, electronic hours or service reports— all managed from the web-based management portal. When mistakes are made, drivers are given an in-cab warning, which includes a grace period to correct the behavior. Should those wrong actions not be corrected, the system notifies management. It is actually a win-win situation for employees and the company, inthinc spokesman Casey Johnson said. “When you have an accident or injury, there is time lost, which is bad for employees and bad for the company. When you reduce accidents and cut down on personal injuries, that increases productivity.” Research shows that companies using smartZones have experienced an approximate 80 percent reduction in speeding problems and accidents, he said. “Typically, we see significant results from the product. We also see a saving in fuel costs through MPG tracking and idle-time mentoring.” For more information, call (866) 294-8637 in the United States, +00-1-801-866-2255 internationally, or e-mail contact@ inthinc.com. Tell them you saw it in AsphaltPro Magazine.
Astec Dashes Info to Producers
The Data Acquisition System Hub (DASH) from Astec, Inc., Chattanooga, is designed to gather information from all plants in an operation and make it accessible via web browser—or flash-compatible device—in a real-time snapshot for asphalt producers. DASH centralizes multiplant management and makes plant data quickly available to facilitate fast management decisions and quick resolution of production problems. In addition, the operation analysis that DASH provides can encourage competition between plants, which means more productivity and efficiency for the company overall. DASH is compatible with Astec control systems TCII, PMII and PMIII, which are discussed in this issue’s World of Asphalt preview on page 48. The type of production data collected from each plant includes mix totals, raw material usage, current produc-
tion rates, moistures and mix temperature. Fuel consumption can be monitored for plants that have fuel meters connected to the plant control system. DASH displays data in interactive pie charts, bar charts, trend graphics and gauges, as seen in the image on page 66. DASH also collects sales data as each sales ticket is printed at each plant. DASH is designed by Astec software engineers and will be installed, supported and serviced by Astec controls engineers and Astec service. For more information, contact Astec at (423) 867-4210 or visit astecinc.com. Tell them you saw it in AsphaltPro Magazine.
Screens and Sifts
Those asphalt producers who have embraced the recycling culture may have visited the USCC Jan. 17 through 20 in Austin, Texas. The world’s largest trade show for the composting, wood waste and organics recycling industry featured live equipment demos at the Texas Disposal Systems composting facility where shredding and grinding OEM Komptech USA, Westminster, Colo., showed different machines used in the composting and biomass industries. Komptech specializes in waste handling and recycling technology, including
machines that can be retrofitted for asphalt shingle grinding. Its machines are made in Austria. For more information, visit www.komptechusa.com. Tell them you saw it in AsphaltPro Magazine.
Eriez Bin Vibrators Shake Out Problems
The line of Hi-Vi electromagnetic bin vibrators from Eriez, Erie, Pa., features 12 AC drive units that are designed to improve the flow of hard-to-handle materials deposited into bins, hoppers and chutes. The bin vibrators include a totally enclosed, patented magnetic drive that can be used for a variety of applications. The Hi-Vi’s concentrated vibration has a powerful positive drive in both directions. For more information, visit http://en-us.eriez.com/ Products/BinVibrators/. Tell them you saw it in AsphaltPro Magazine.
Terex Remixes Paver Design The new CR652RX remix anti-segregation system mainline paver from Terex®, Oklahoma City, features the largest rubber tire drive in the industry, according to the manufac-
equipment gallery turer, to enhance tractive effort. This allows paving widths reaching up to 30 feet (9.1 meters). Many of the same features contractors saw on the Terex CR662RM RoadMix paver/MTV are on the new 10-foot (3-m) CR652RX rubber-tire paver. With outboard drive spreading augers and a new generation remix anti-segregation system, this new baby is designed to enhance paving quality and efficiency by preventing material and thermal segregation. The technology is discussed more in the World of Asphalt preview on page 48. The new spreading auger design uses two outboard drive motors mounted to the tractor’s rear bulkhead. Two 5-foot (1,524-mm) long spread auger sections deliver material to the left and right sections of the screed. Each screw auger features its own speed control, allowing operators to independently adjust material flow to either side of the screed. The auger sections back up to each other, leaving no separation in the center. This new drive and screw auger arrangement is to reduce centerline segregation and eliminate the need for reversing augers and the center gearbox. Two sets of counter-rotating augers with interleafing flights uniformly draw down material from all areas of the hopper and re-blend the asphalt to produce a homogenous mix. The entire length of the auger shafts is lined to reduce wear.
68 February 2012
Positioned at or below hopper wing level, the augers feature a constant 12-inch (305-mm) diameter, so material is pulled from directly above the full length of the shafts. A large, variable-pitch design—10 inches (254 mm) at the front of the hopper to 12 inches (305 mm) just before the feed tunnel—channels material from the hopper to the spreading augers, which should increase truck exchange efficiency. The augers’ sloped design results in a larger opening at the end of the feed tunnel, which eliminates material build-up. Upon exiting the hopper, asphalt enters the feed tunnel’s approximately 8-foot (2.4-m) long mixing zone under the engine compartment. Here, 100 percent of the uniformly drawn-down material is mixed in a figure-eight pattern by the pugmill-style mixers as it’s channeled to the spreading augers. Standard receiving hopper capacity of the CR652RX paver is 16.7 tons (15 tonnes). It’s designed to handle more than a 900-TPH (916.5 metric TPH) capacity. A 260-horsepower (191 kW) Cummins QSB6.7 diesel engine powers the paver and contractors can choose among three screed models on the back end. For more information, contact Mark Oehmke at (405) 491-2046 or Mark.Oehmke@terex.com. Tell them you saw it in AsphaltPro Magazine.
RAP-13424 2002 CMI PTD-300 Portable CF Drum Mix Plant
PTD-300 - Drum Mixer 7’x8’-3”x42’ w/ Hauck SJ520 Burner RA-218P - Portable Roto-Aire Baghouse, 504 Bags, 9,072 Sq. Ft. PAB-532 - (5) 32 Ton Bin Portable Cold Feed System SE-195 - 95 Ton Self Erect Surge Silo CT20/10P - 30k gallon AC Tank, 20/10 Split CEI 1500 1.8mbtu Hot Oil Heater
RAP-13055 CEDARAPIDS E500 CF DRUM
• 114” x 52’ long w/ 126 mbtu burner • Shell thickness close to ½” throughout • Rap collar, trunnion drive, left side discharge
VIST US ON THE WEB OR CALL TOLL FREE
Inc.
PO Box 519, Shelbyville KY 40066 • Fax 502.647.1786
www.ReliableAsphalt.com 866.647.1782
here's how it works
Diamond Key’s Bitumen Loading Module
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itumen loading at terminals doesn’t have to be rife with safety hazards. The engineers at Diamond Key International, Victoria, Australia, addressed the complex aspects of top loading, compartment overfill, fume removal and more with the DKI Bitumen Loading Module. Here’s how it works. Liquid bitumen travels from a holding tank through a pipe to the bitumen loading module in the loading bay area. When a tanker truck arrives at the loading bay, an operator climbs the stairs to the platform loading level. From within the orange shelter, he first controls the drawbridge via electric push buttons, sending the bridge “out” with pneumatic cylinders that 70 February 2012
control its movement up and down. He lowers the drawbridge with the drive system to just above the truck barrel to avoid contact (thus dents) with the truck’s soft external insulation and shell. Second, the operator walks onto the drawbridge, taking the loading arm until it vertically aligns with the truck barrel hatch. The arm has articulated joints for maneuverability and extension capability. Third, the operator inserts the arm into the truck barrel and then walks back to the orange control station. He observes loading from within the orange shelter where all the loading controls are located. He also has easy access to a waist-high 3-minute deadman switch here.
During the loading process, the driver is away from the loading point, avoiding the possibility of venting steam and burns, splash back, or fume exposure. The pneumatic safefil detection system signals when the tanker has reached safe capacity and automatically ceases flow of bitumen. When the tanker is loaded, the operator performs tasks in reverse and the loading information is sent to the office for the bill of lading to be printed. When cleared, the driver stops by the office to pick up the BOL before leaving the refinery. For more information on the DKI Bitumen Loading Module, available in Australia and the Pacific Rim, contact David Moss at DavidMoss@diamondkey.com or visit www.diamondkey.com.
here's how it works
Gilson’s SG-4
W
hen the lab tech needs to determine bulk specific gravity, whether he has an asphalt core or gyratory specimen to test, he can start with the AASHTO TP 82 Provisional Specification for guidance on operation of the SG-4 from Gilson Co., Inc., Lewis Center, Ohio. The SG-4 uses a patentpending, computer-controlled system to measure water displacement without consumable products. The proprietary software is preloaded on the computer component of the SG-4 and allows for initiation of the test, measurement based on the displacement of water, and calculation of bulk specific gravity of the asphalt core or gyratory specimen. Here’s how it works. First, the tech enters the sample information, including sample ID and weight 72 February 2012
of the dry asphalt specimen into the program. He determines the initial volume of water with just the sample holder in the water-filled measuring chamber. Next, the tech removes the sample holder from the chamber and sets the core or gyratory sample on the holder. He re-inserts it into the measurement chamber where it rests for approximately 5 to 10 seconds. The final step is completely computer controlled as the sample’s weight compared to the determined displaced volume then allows for the calculation of the sample’s specific gravity. This data is displayed on the computer screen. The computer allows the user to determine the specific gravity measurements from start
to finish in about 45 to 60 seconds, according to the manufacturer, saving the results, sample weight, SG and file name. The system closely controls variables, such as the initial water level and volume change after the sample is placed in the SG-4 chamber, to assure accuracy and improve repeatability. The computer controls the water level within a tolerance necessary to maximize repeatability and accuracy. If the water level goes below the necessary level, the computer instructs the tech to adjust the water until it’s within the required tolerances. For more information, contact Jim Bibler at (740) 548-7298 or jbibler@ gilsonco.com, or visit www.globalgilson.com.
resource directory ACE Group................................................ 25, 71 Contact: Carl McKenzie Tel: 888-878-0898 sales.enquiries@asphaltacesales.com www.asphaltace.com Asphalt Drum Mixers.....................27, 46-47 Contact: Steve Shawd or Jeff Dunne Tel: 260-637-5729 sales@admasphaltplants.com www.admasphaltplants.com Asphalt Plant Products............................... 73 Contact: Tom Holley Tel: 866-595-3268 • Cell: 706-466-3678 www.asphaltplantproducts.com Astec, Inc..................................... 23, 36-37, 54 Contact: Tom Baugh Tel: 423-867-4210 tbaugh@astecinc.com www.astecinc.com B & S Light Industries............................28-29 Contact: Mike Young Tel: 918-342-1181 Sales@bslight.com www.bslight.com Brookfield Engineering.............................. 51 Sales@brookfieldengineering.com Tel: 800-628-8139 or 508-946-6200 www.brookfieldengineering.com
Bullis Fabrication........................................... 51 Contact: Greg Bullis Tel: 866-981-8965 gregbullis@bullisfabrication.com www.bullisfabrication.com C.M. Consulting............................................. 54 Contact: Cliff Mansfield Tel: 541-354-6188 CMConslt@aol.com www.hotplantconsulting.com CEI..........................................................................4 Contact: Andy Guth Tel: 800-545-4034 info@ceienterprises.com www.ceienterprises.com Clarence Richard Co.................................... 68 Contact: Clarence Richard Tel: 952-939-6000 Carrie@clarencerichard.com www.clarencerichard.com Dillman Equipment...............................18-19 Tel: 608-326-4820 www.dillmanequipment.com Dynapac US.................................................... 11 Tel: 800-732-6762 www.dynapac.us
E.D. Etnyre........................................................ 52 Contact: sales@etnyre.com Tel: 800-995-2116 www.etnyre.com EZ Street.................................................... 65, 67 Tel: 800-734-1476 Info@ezstreet-miami.com www.ezstreetasphalt.com Hauck Manufacturing................................. 49 Contact: Michael Blantz Tel: 717-272-3051 Mblantz@hauckburner.com www.hauckburner.com
KPI-JCI and Astec Mobile Screens.................................. 31 Contact: Lisa Carson Tel: 605-668-2425 lisacarson@kpijci.com www.kpijci.com
Stansteel AsphaltPlant Products................................ 55 Contact: Dave Payne Tel: 800-826-0223 dpayne@stansteel.com www.stansteel.com
Libra Systems................................................ .53 Contact: Ken Cardy Tel: 225-256-1700 Sales@librasystems.com www.librasystems.com
Stansteel................................................... .13, 33 Contact: Dawn Kochert Tel: 800-826-0223 dkochert@hotmixparts.com www.hotmixparts.com
Maxam Equipment............................... 15, 43 Contact: Lonnie Greene Tel: 800-292-6070 lgreene@maxamequipment.com www.maxamequipment.com
Heatec, Inc.......................Inside Front Cover Contact: Sharlene Burney Tel: 800-235-5200 sburney@heatec.com www.heatec.com
Reliable Asphalt Products...................................Back Cover, 69 Contact: Charles Grote Tel: 502-647-1782 cgrote@reliableasphalt.com www.reliableasphalt.com
Herman Grant Co., Inc................................ 35 Contact: Paula Shuford Tel: 800-472-6826 hg@hermangrant.com www.hermangrant.com
Roadtec........................................................... 7, 9 Contact: Sales Tel: 423-265-0600 Sales@roadtec.com www.roadtec.com
Homestead Valve.......................................... 21 Tel: 610-770-1100 Sales@homesteadvalves.com www.homesteadvalves.com
Rotochopper, Inc................................Inside Back Cover Tel: 320-548-3586 Info@rotochopper.com www.rotochopper.com
Systems Equipment..................................... 41 Contact: Dave Enyart Sr. Tel: 563-568-6387 Dlenyart@systyemsequipment.com www.systemsequipment.com Tarmac International, Inc........................... 17 Contact: Ron Heap Tel 816-220-0700 info@tarmacinc.com www.tarmacinc.com Top Quality Paving....................................... 68 Contact: John Ball Tel 603-624-8300 Tqpaving@yahoo.com www.tqpaving.com World of Asphalt........................................... 63 Contact: info@worldofasphalt.com Tel: 800-867-6060 www.worldofasphalt.com
AsphaltPro’s Resource Directory is designed for you to have quick access to the manufacturers that can get you the information you need to run your business efficiently. Please support the advertisers that support this magazine and tell them you saw them in AsphaltPro magazine.
www.theasphaltpro.com | ASPHALT PRO 73
the last cut
Non-OPEC Outlook Forecasts Growth by the Energy Information Administration
M
arkets often focus on anticipated crude oil production from members of the Organization of the Petroleum Exporting Countries (OPEC) as a key driver of supply/demand tightness. Such attention is understandable given the return of Libyan production, reports of record-high Saudi production, mixed news from Iraq…and now further sanctions against Iran by the United States and other countries. However, crude and liquid fuels production in countries outside of the OPEC accounts for most of the world’s production (59 percent in 2011), making prospects for non-OPEC production critical to the outlook for world oil markets. The U.S. Energy Information Administration’s (EIA) January Short-Term Energy Outlook (STEO) forecasts non-OPEC crude and liquid fuels production to grow by 0.9 million barrels per day (bbl/d) in 2012, followed by growth of 0.8 million bbl/d in 2013. Taking account of projected growth in the supply of crude and liquid fuels from both OPEC and non-OPEC suppliers, EIA anticipates the recent tightening of world oil markets will moderate somewhat in 2012, as the projected growth in supply outpaces the anticipated growth in demand. Total crude and liquid fuels production in 2012 is expected to grow by about 1.4 million bbl/d and projected demand will increase by about 1.3 million bbl/d. This easing is expected to be relatively short-lived, as projected consumption growth of about 1.5 million bbl/d in 2013 outpaces non-OPEC supply growth in that year. Because non-OPEC countries account for so much production, non-OPEC crude and liquid fuels production growth is a major source of uncertainty surrounding the outlook for oil prices. In recent years, initial forecasts of non-OPEC production have often missed the mark by a considerable margin. These revisions have reflected unpredictable events such as supply disruptions, shut-ins and technical difficulties, as well as the effects of better-than-expected recovery rates and higher-than-expected decline rates. Non-OPEC production growth for 2012 and 2013 should be dominated by the Western Hemisphere. U.S., Canadian and Brazilian supplies continue to expand, more than offsetting continued…declines in Mexico. Each of the three former countries is expected to show growth of between close to 325,000 bbl/d and 340,000 bbl/d over the twoyear forecast period. Other non-OPEC countries expected to show production growth include China and Kazakhstan at between 220,000 bbl/d and 250,000 bbl/d over the next two years. EIA estimates that U.S. crude oil and liquid fuels production averaged 9.95 million bbl/d in 2011, an increase of
74 February 2012
260,000 bbl/d over 2010. Total crude oil and liquid fuels production in 2012 is expected to rise by an additional 210,000 bbl/d…Expected production increases in 2012 and 2013 are supported mainly by expanding shale oil production. The STEO projects that U.S. crude oil and liquid fuels production will total 10.2 million bbl/d in 2012 and 10.3 million bbl/d in 2013. In contrast, Russia looks set to contract in 2012-2013. North Sea and Mexico crude oil and liquid fuels production is also expected to fall. Source: Feb. 1, 2012, TWIP report of EIA. Liquid Asphalt Cement Prices—average per ton Company, State
Oct ’11
Nov ’11
Dec ’11
Jan ’12
$550.00
$550.00
$570.00
$570.00
NuStar Energy, Ga.
580.00
580.00
580.00
600.00
ConocoPhillips, Tenn. NuStar Energy, N.C.
580.00
580.00
580.00
600.00
NuStar Energy, Va.
595.00
595.00
600.00
600.00
Assoc’d Asphalt Inman, N.C.
580.00
580.00
600.00
600.00 600.00
Assoc’d Asphalt Inman, S.C.
575.00
575.00
600.00
Assoc’d Asphalt Inman, Va.
590.00
590.00
605.00
605.00
Marathon Petroleum, Tenn.
540.00
540.00
560.00
560.00
Marathon Petroleum, N.C.
565.00
555.00
575.00
575.00
na
na
na
610.00 610.00
Valero Petroleum, N.C. Valero Petroleum, Va.
580.00
580.00
580.00
Massachusetts Average
575.00
575.00
575.00
575.00
California Average
559.80
637.00
625.00
595.00
Missouri Average
510.00
510.00
526.25
640.00
Colorado Average
429.28
490.62
485.92
na
Data for Southeast region, Source: ncdot.org; Data for Massachusetts, Source: mass.gov; Data for California, Source: dot.ca.gov; Data for Missouri, Source: modot.mo.gov; Data for Colorado, Source: CDOT and Cenovus
Crude Oil Activity (U.S. Crude) futures spot data
stocks
Diesel Fuel Retail Price (dollars per gallon)
Oct 7
$82.98/bbl
337.6 m bbl
Oct 10
3.721
Oct 14
$86.80/bbl
332.9 m bbl
Oct 17
3.801
Oct 21
$87.40/bbl
337.6 m bbl
Oct 24
3.825
Oct 28
$93.32/bbl
339.5 m bbl
Oct 31
3.892
Nov 4
$94.26/bbl
338.1 m bbl
Nov 7
3.887
Nov 11
$97.78/bbl
337.0 m bbl
Nov 14
3.987
Nov 18
$97.41/bbl
330.8 m bbl
Nov 21
4.010
Nov 25
$96.77/bbl
334.7 m bbl
Nov 28
3.964
Dec 2
$100.96/bbl
336.1 m bbl
Dec 5
3.931
Dec 9
$99.41/bbl
334.2 m bbl
Dec 12
3.894
Dec 16
$93.53/bbl
323.6 m bbl
Dec 19
3.828
Dec 23
$99.68/bbl
327.5 m bbl
Dec 26
3.791
Sources: Energy Information Administration