SA Mechanical Engineer June 2018

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S MECHANICAL A ENGINEER June 2018

Publication of the SA Institution of Mechanical Engineering, incorporating News of Associate Organisations

REGIONAL CONNECTIVITY CONFERENCE: KYALAMI 11 & 12 JULY ENGINEERS ARE THE PROBLEMSOLVERS OF OUR COLLECTIVE FUTURE


THESE BRANDS SUPPORT RESPONSIBLE RECYCLING OF USED OIL

Support brands that care for the environment Use ROSE approved collectors and recyclers to dispose of your used oil. 021 448 7492 • usedoil@iafrica.com • www.rosefoundation.org.za 2

THE SOUTH AFRICAN MECHANICAL ENGINEER

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AN ENGINEER’S VIEW

Online education Online education is growing quickly. Gone are the days where universities were the sole custodians of knowledge. Today we have unprecedented access to information and we are free to learn in near arbitrary depth in almost every imaginable field. A quick scan through Wikipedia can confirm how inertia is calculated in a moving reference frame, and YouTube will teach you how to replace a light bulb on your car. Most of us think that the learning stops there but the Internet can provide us with so much more.

A

Martin Venter

s a group we are curious and enjoy learning, in our professional lives we are required to hone existing skills and develop new ones, but are plagued by extensive time commitments and a rapidly changing schedule that often prevents us from committing to the limited number of short courses presented locally.

organisations listed make some capstone module available where the participant can engage in an extended application of the theory in a project setting with supervision. These are typically bundled into a mini-diploma style collection or specialisation. In some cases these can extend to full degree programmes.

Online platforms offer a wider variety of courses with significantly more flexibility, in content timing and mode of participation. Modern online courses are truly massive and benefit from very strong community interaction. It is not uncommon to be enrolled in a course with 60 000 other students, most of whom are happy to communicate via the forums.

The University of Illinois for instance has shifted their 2 year Masters degree in Machine Learning to the Coursera platform and whether you are a resident student or online participant you will have access to the same resources. Though some of the courses can be pricey, most will be credit bearing and provide a course certificate for around $15 - $100. Almost all will allow you to audit content and participate in the online forum for free.

Experts

There are many strong online institutions but three organisations stand out, Coursera.org, Udemy. com and Edx.org. Each of these organisations afford anyone the opportunity to participate in courses presented by experts from well established universities including familiar institutions such as Harvard, Stanford, MIT and TU Delft. Over the past few years I have participated in courses ranging from statistical modeling presented by John’s Hopkins to geographical information systems presented by the US Army Academy. The courses range from 4 to 12 weeks and require a commitment of between 4 and 12 hours a week. Video lectures and course materials are provided, with graded assessments and an active mentor community. The courses range from introductory courses to advanced postgraduate level. In some cases, the courses even bear credit at their host university. Although courses are available on a wide range of topics most fields are limited to a digital footprint, and you are not likely to get your hands dirty. Most will provide you with the theory and rely on the participants to create their own applications. With this in mind each of the three

In some cases, the courses even bear credit at their host university

Sealability Although this style of online education is not likely to replace a conventional engineering degree in South Africa any time soon, it is likely that we will be seeing similar courses make their way into the existing university curriculum as an efficient teaching tool that scales well to large groups. For those of you with your degree under your belt, there is an opportunity to up-skill yourself and your employees with some confidence without taking on the burden of creating your own programmes or relying on local 3rd party providers. With a small time investment these flexible courses will allow you to develop up to date technical skills in new fields or refine skills from years past. It might be a practical way to transition from one field to another or provide you an edge in your current organisation.

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Your boutique business destination Surrounded by lush gardens in the hub of Johannesburg’s northern suburbs, The Peartree in Craighall Park caters for groups of two through to 100 guests in nine well-appointed and equipped business suites. Breakfast meetings, working lunches, indoor or outdoor dining, half-day and full-day packages including all welcome refreshments, teas and lunches are offered in Standard, Gold and Platinum packages. Secure parking, business centre, fibre optic broadband AV, lockable space, all underpinned by highly qualified and helpful staff dedicated to ensuring your event is a success, make The Peartree a destination of choice.

www.thepeartree.co.za e-mail: info@thepeartree.co.za Tel: 011 781 1401 41 St. Albans Ave, Craighall Park

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S MECHANICAL A ENGINEER June 2018  VOLUME 68

On the Cover

eltherm South Africa (Pty) ltd Tel: (011) 326-6475 Email: info@eltherm.co.za, www.eltherm.co.za

Cover Story

Contents

Pumps

10 Specialist in Electrical Heat Tracing

24 Controlled-temperature test units

Lubrication

26 Production of the Audi A8

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RFID Technology

Lubricating for a longer life

Software

29 Functioning as a Team

Networking

12 Regional Connectivity Conference

Biological Treatment

20 Recycling Waste Water is Key

Letting our Capes Fly

14 Why Engineers are awesome

Separation Technologies

33 Making Tailings a Valuable Product

Valves

16 Not Just a Commodity 18 Automatic Slurry Feed Splitter 20 Low Shear Control Technology

Power Transmission

23 From HVAC to Wine Farms and Mining

Regulars 3 6 35 38

An Engineer’s View Institution News Market Forum On the Move

Copyright

All rights reserved. No editorial matter published in “SA Mechanical Engineer” may be reproduced in any form or language without written permission of the publishers. While every effort is made to ensure accurate reproduction, the editor, authors, publishers and their employees or agents shall not be responsible or in any way liable for any errors, omissions or inaccuracies in the publication, whether arising from negligence or otherwise or for any consequences arising therefrom. The inclusion or exclusion of any product does not mean that the publisher or editorial board advocates or rejects its use either generally or in any particular field or fields.

Produced by: PROMECH PUBLISHING, P O Box 373, Pinegowrie, 2123, Republic of South Africa Tel: (011) 781-1401, Fax: (011) 781-1403 Email: samecheng@promech.co.za, www.promech.co.za Managing Editor Susan Custers Editorial Contributors Advertising Sales: Louise Cresswell Liesl Venter/Patricia Holburn Cell: 071 886 1263 Circulation Belinda Siegruhn DTP Anne Rotteglia Subscriptions Please email us at accounts@promech.co.za if you wish to subscribe to “SA Mechanical Engineer” at R550,00 (excl postage and VAT) per year; R1 380,00 per year for Africa/Overseas. Disclaimer

PROMECH Publishing and The South African Institution of Mechanical Engineering as well as any other body do not take responsibility for the opinions expressed by individuals.

Printed by: Typo Colour Printing, Tel: (011) 402-3468/9 FSC (Forestry Stewardship Accreditation)

Official Publication of THE SA INSTITUTION OF MECHANICAL ENGINEERING and endorsed by:             

CONSULTING ENGINEERS OF SA CORROSION INSTITUTE OF SA INSTITUTE FOR CERTIFICATED MECHANICAL AND ELECTRICAL ENGINEERS NATIONAL SOCIETY OF BLACK ENGINEERS NUCLEAR INSTITUTE SA ASSOCIATION FOR ENERGY EFFICIENCY SA CAPITAL EQUIPMENT EXPORT COUNCIL SA INSTITUTE FOR NON-DESTRUCTIVE TESTING SA INSTITUTE OF TRIBOLOGY SA PLASTIC PIPE MANUFACTURERS ASSOCIATION SA PUMP MANUFACTURERS ASSOCIATION SA VALVE AND ACTUATORS MANUFACTURERS ASSOCIATION VALVE & ACTUATOR MANUFACTURERS CLUSTER OF South Africa

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SA INSTITUTION OF MECHANICAL ENGINEERING

Council 2016 - 2018 Office Bearers President............................................ Prof JL van Niekerk (Wikus) Vice President........................................................ A Roos (Andre) National Treasurer................................... G van den Berg (Gideon)

Branch Chairpersons Central ................................................................. C Kruger (Carel) Eastern Cape........................................... G van den Berg (Gideon) KwaZulu-Natal ........................................ Dr J Padayachee (Jared) Mpumalanga Highveld .....................................N Lecordier (Noel) Vaal.............................................................. N Swanepoel (Niekie) Western Cape ............................................... Dr M Venter (Martin)

Portfolios: Communications and Marketing..................G Bartholomew (Bart) Technology Programme..................................... SZ Hrabar (Steve) Engineering Education and Constitutional Matters.....Dr D Blaine (Debby)

127th SAIMechE National Annual General Meeting

TBC......................................................H Makwarela (Hangwane)

Members are invited to attend the 127th National AGM

Chief Executive Officer: Vaughan Rimbault National Office Manager: Anisa Nanabhay PO Box 511, Bruma, 2026 Tel: (011) 615-5660 Email: info@saimeche.org.za Website: www.saimeche.org.za

Date: Wednesday, 1 August 2018

Membership Email: membership@saimeche.org.za

Venue:ECSA’s Offices, Bruma (Jhb) Time: 17h45 for 18h00

Company Affiliates Amoricom

Megchem

Autodesk as represented by Worldsview Technologies

Mod-U-Flow CC

Ainsworth Engineering (Pty) Ltd Alstom Power Service SA (Pty) Ltd

PaCMan Projects & Maintenance Plant Design & Project Services (Pty) Limited (PDPS)

Bosch Projects Pty Ltd

PPS Insurance Co Limited

Esteq Group (Pty) Ltd

Rotek Engineering

Exxaro Resources (Pty) Ltd

S.A.M.E Water (Pty) Ltd

Festo (Pty) Ltd

SA Power Services (Pty) Ltd

Kelvion Thermal Solutions (Pty) Ltd Green Plan Consultants (Pty) Ltd Hatch Africa (Pty) Ltd Howden Power (a div of Howden Africa) Howden Projects (a div of James Howden) MBE Minerals (SA) (Pty) Ltd

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Osborn Engineered Products SA (Pty) Ltd

Babcock Ntuthuko Engineering Pty Ltd

Fluor SA (Pty) Ltd

After the Annual general meeting all guests are invited to join the President, and Council for dinner and drinks whilst networking with like-minded individuals The AGM notice including full details is available at: www.saimeche.org.za

Sasol Technology (Pty) Ltd Siemens Ltd Simera Technology (Pty) Ltd Spirax Sarco (Pty) Ltd Tenova Mining and Minerals SA Thyssenkrupp Engineering (Pty) Ltd Vital Engineering (Pty) Ltd Weir Minerals Africa

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SA INSTITUTION OF MECHANICAL ENGINEERING

Vaughan Rimbault, Uzair Kaka, Edward Rycroft, Nduduzo Simamane, Prof Robert Reid

SAIMechE R Sharp awards

M

r Ralph G. Sharp (Hon FSAIMechE) was a former Chairman of the SAIMechE KZN Branch, long standing member and great friend of the Institution. He was recognised for his immeasurable contribution to the Institution and engineering profession when he received his Honorary Fellowship in 2007. His passing was a great loss to the Institution and the profession. He was a brilliant engineer, a fine man and an excellent mentor. Those who knew him were very fond of him.

Students were notified about the funds, and given an opportunity to apply for this. Although there were various factors taken into account, consideration was given to both academic record and financial need. Following consultation between Wits and SAIMechE, these students from Wits University were selected:

Ralph had entrusted SAIMechE with an endowment from his estate, to provide bursaries or grants to students studying mechanical engineering at Wits and UKZN.

SAIMechE congratulates these students and wishes them the very best in their future endeavours.

• Nduduzo Simamane • Uzair Kaka • Edward Rycroft

VISIT US! 10 – 14 September 2018 | Expo Centre, Nasrec, Johannesburg, South Africa BRINGING YOU THE FUTURE OF MINING, MANUFACTURING, ELECTRICAL AND POWER SINCE 1972

VOL 68 June 2018 7 IT’S A SHOW THAT BELONGS TO YOU.

THE SOUTH AFRICAN MECHANICAL ENGINEER


SA INSTITUTION OF MECHANICAL ENGINEERING

Centrifugal Pumps, Systems and Slurry Applications Seminar

Event Code : EPM18 - Event Date : 6-7 August 2018 Booking Closing Date : 27 July 2018

CPD accreditation number SAIMechE-1028-12/19 2 credits may be obtained under Category 1

Standard Fee : R5 170.00 + VAT

expertise and venue kindly supplied by Weir Minerals

Programme, registration form, and fee structure (including discounts) may be obtained from Carey Evans Tel: 031 764 7136 or carey@saimeche.org.za 2018 Forthcoming Training Workshops SAIMechE Training Events should be viewed by members and the industrial community as service benefits. Only events which have attracted sufficient delegates will take place. Events which do not have sufficient delegates by their bookings closure dates will be cancelled and all relevant parties will be notified accordingly. Therefore, if you book on an event, we recommend that you delay making your travel arrangements until you have been notified that the event will take place as planneWorkshop programmes, 2018 Delegate registration forms, and Fees structure may be obtained from Carey Evans Tel: 031 764 7136 or email: carey@saimeche.org.za Event Code Event Title

Date Start

Region

Booking Closure Date

2 August

Cape Town

22 July

2 August

East Rand

22 July

Date End

Developed and presented by: David Ramsay, B.Sc (Civil Eng.), MEngMan, MSAICE, COMENSA C9818

Leadership and Project Management for Engineers Workshop

1 August

Presented by: Malcolm Black, B.Sc.(Mech.Eng.), G.C.C., MSAIMechE, Th.B. AE0318

Steam Distribution, Pipeline and Ancillaries, Steam Flow Metering, and Desuperheating Workshop (Material supplied by Spirax Sarco)

1 August

Developed and presented by: Dr. Herbert De Vries, B.Sc (Mech.Eng), Pr.Eng. G.C.C., MSAIMechE, MBL, DBL E3718

Pressure Vessel Design, Construction, Maintenance & Troubleshooting Workshop

15 August

15 August

East Rand

3 August

Developed and presented by: Dean Sawich, BSc, AAS A1218

The Psychrometrics Toolbox Its Principles, Uses and Applications Workshop

15 August

16 August

Durban

3 August

E1218

The Psychrometrics Toolbox Its Principles, Uses and Applications Workshop

19 September

20 September

East Rand

7 September

Developed and presented by :Dr. Anton Maneschijn, Ph.D. (Eng.), M.Sc. (Aero. Eng.), B.Sc. (Mech. Eng.), Pr. Eng. (Aero.), FRAeS E8918

Applying the Engineering Design Process in a Policy-Based Environment Workshop

22 August

22 August

East Rand

Special Offer on In-House Training Workshops • Save up to R2,735.00 per delegate by booking workshops totalling 6 days or more. • Save paying delegate travel costs. We will travel to you! • Work as a corporate team by sharing and solving common problems as you learn. • Ask the developer to tailor the material or training methods to suite your corporate requirements. To learn more about our 2018 special In-house training offer, please contact: Linda Robinson at Tel: 031 764 7136 or email: linda@saimeche.org.za.

TRANSNET FREIGHT RAIL www.transnetfreightrail-tfr.net 8

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10 August


LUBRICATION

Lubricating for a longer life An extensive range of sealing products encompasses Spanjaard lubricants, oils and greases, which are suitable for industrial, automotive, marine, mining and consumer applications.

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he effects of friction and the resulting wear of moving components, are significantly reduced by effective lubrication. The purpose of any lubricant, which may take the form of an oil, a grease or a solid, is to separate the mating surfaces and thereby reduce friction and wear. “For this reason, lubrication is considered to be one of the most important aspects of most industrial equipment and machinery maintenance programmes,” says Marc Gravett, business unit manager, seals, BMG. “Not only do lubricants, oils and greases extend the service life of machinery and equipment, but they also play an important role in enhancing performance of components, like bearings and industrial chain.

All factors

“Lubrication-related failures in machinery are generally preventable and can be avoided with the application of the correct lubricant, at the right time. A general multipurpose grease is adequate in many applications, but more arduous operating conditions demand the judicious selection of the correct lubricant and lubrication system. “In selecting the suitable lubricant for a specific application, cognisance must be taken of factors such as speed of relative movement, ambient and operating temperatures, loading, vibration and the environmental operating conditions. “Although lubrication constitutes a small percentage of a company’s maintenance budget, the correct use of appropriate lubricants, results in minimal downtime, extended service life of components and significant operational cost savings,” Marc adds. BMG’s extensive portfolio of locally manufactured Spanjaard lubricants and allied chemical products have been principally formulated to improve performance of equipment and machinery and to enhance maintenance in heavy-duty applications.

Number of solutions

Spanjaard industrial products includes anti-seize compounds and penetrants, assembly and disassembly products, chain lubricants, transmission oils, cleaners and degreasers, electrical maintenance products, plastic moulding and cutting compounds, as well as engineering and fabrication materials. Also available are a number of Spanjaard greasing solutions, including open gear lubricants and wire rope dressings; bearing and synthetic bearing greases, as well as other general grease products. BMG’s technical resources team offers an oil analysis service, which consists of laboratory based sampling and analysis, as well as on-site analysis and filtra-

tion and flushing. Other services include technical applications consulting, product and system design, product quality control and assurance, as well as condition monitoring services.

Output and reliability

The company’s mobile technicians, with specialist technical skills, conduct breakdown and routine maintenance on plant. This team carries out trouble-shooting and advises on possible productivity improvements, to ensure the highest level of plant output and reliability. Specialist services include installation, adjustment, replacement and maintenance of components, shaft and pulley alignment, balancing, condition monitoring, oil sampling and analysis and critical equipment inspections and lubrication schedules. Maintenance training and fault diagnosis also form an important part of BMG’s field services.

Integrated approach

Through BMG’s focus on entire production processes, which combines a comprehensive range of quality components, engineering solutions, technical services and dependable support, companies can access all critical production efficient products and services from one reliable supplier. This integrated approach guarantees lower production costs and higher efficiencies.

Cognisance must be taken of factors such as speed of relative movement, ambient and operating temperatures, loading, vibration and the environmental operating conditions.

The company’s recently upgraded distribution centre - BMG World - centralises functional and support operations onto one site. This enables BMG to continue to provide high levels of operating efficiencies and delivery service, in line with continued growth of the business. Marc Gravett, Business Unit Manager, Seals, BMG Mobile: (082) 572-1415, Tel: (011) 620-1575 Email: marcg@bmgworld.net, www.bmgworld.net

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COVER STORY

Specialists in Electrical Heat Tracing When eltherm was established in South Africa, many questioned the need for heat tracing systems in a country where temperatures are much higher than Europe. The company soon made its mark by finding new applications for its products across a wide range of industries. “SA Mechanical Engineer” met with Andrea Hector, GM of eltherm South Africa (Pty) LTD, who tells us that the company is well established in the local market. “Most industries that require electrical heat tracing are familiar with eltherm and its products. The industry in South Africa is aware that eltherm has a knowledge base and offers a turnkey solution that includes design, installation, commissioning and maintenance; together with a world class product.”

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he business was started in 1991 as a small privately-owned German concern. In 1996, eltherm GmbH moved into new production facilities specialising in electrical heat tracing. Five years ago the company, which predominantly serviced the German economy and industry, was acquired by Indus Holding AG. A listed organisation, Indus Holding AG has a strong portfolio organised into five segments, which include; construction/infrastructure, automotive technology, engineering, medical technology and metals technology.

Heat tracing material is an electrical cable that is used to maintain the temperature of a product Since the Indus acquisition, eltherm has grown organically expanding its production facilities, opening its first subsidiary in 2010, eltherm AsiaPacific LTD in Singapore. Since then, a further six subsidiaries have been established. The growth of eltherm over this period, year-on-year is well over 20%, which is significant. Although products were initially distributed by a local distributor, eltherm South Africa (Pty) LTD was established in 2014 in Sandton, Johannesburg. Today it has a staff complement of around 35 to 40 people, depending on the number of contractors working on site at any given time. “People are critical to the success of eltherm South

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Africa”, says Andrea, “The focus is on the customer experience which starts from the person who answers the phone to those involved in systems, quality and commissioning which all make for a professional customer experience,”

Numerous applications for industry

The company offers tailored systems for specific applications. Andrea explains that every system is unique as is every requirement. “By offering the best German engineered products with the best knowledge on electrical heat tracing, our systems improve efficiencies.” Heat tracing material is an electrical cable that is used to maintain the temperature of a product. It does not heat up a product. When bitumen, for example, comes out of a tanker or pipe, it is already at a specific temperature. This temperature needs to be maintained as the product is transported from point A to point B. eltherm will maintain the heat of the system, including pumps, valves, pipes and tankers to ensure there are no temperature losses. “When you start looking at the application of our products required by industry, you realise that the market is significant,” she adds.

A dominant player in local power stations

The company is also very dominant in the power industry in South Africa. eltherm designed the electrical heating system for the Medupi Power Station as well as designing and supplying the electrical heat tracing requirements for Kusile power station. Kusile and Medupi will be the third and fourth largest coal-fired power plants in the world.

June 2018


The eltherm South African team

At Medupi, electrical heat tracing is essential. eltherm supplied the full heating system including the control and monitoring system, product, assembly, commissioning, installing and documentation.

Concentrated solar power

In 2015 during their first full year of operation, the company signed a contract for the Xina Solar One Concentrated Solar Plant (CSP) in South Africa. Locally, there are five CSPs, all located in the Northern Cape, with plans by Eskom and the government to add to this number with the signing of the REIPPP by Energy Minister, Jeff Radebe on 4th April 2018. “The REIPPP has a significant impact on the economy. International investment will contribute to the shortages in electricity. Concentrated solar energy means we can produce electricity after dark, even though the power source is solar,” Andrea explains. “Heat tracing is required at CSP plants to maintain temperature and prevent subsequent heat loss. eltherm’s EHT system pre-heats empty pipes and equipment to maintain the correct temperature throughout the plant’s storage process, which avoids solidification of fluids. It also compensates for the loss of heat when fluids flow to pipes with a lower ambient temperature. Plants are able to harvest the day’s solar energy by heating up molten salt to approximately 480°C and storing it. This allows for a five-hour thermal energy storage solution which assists meeting peak demand after sunset. At night, molten salt is used to generate enough heat to create steam which generates energy.”

Since Xina Solar One, eltherm South Africa has been awarded the electrical heat tracing contracts for Ilanga Solar Thermal Power Plant CSP and Kathu Solar Park CSP. eltherm Global accounts for approximately 70% of heat tracing in the CSP industry.

The eltherm team of dedicated staff has made significant inroads into the electrical heat tracing industry in South Africa since 2014 On the continent

The past three years have also seen the company developing applications in other industries such as bitumen, Tank Tainers and road tankers. Tank Tainers are used on ships to transport any product from one country to another. These are heated, using electrical heat tracing systems to maintain a certain temperature for a long period of time. “The eltherm team of dedicated staff has made significant inroads into the electrical heat tracing industry in South Africa since 2014. Our approach was to take our time establishing ourselves in South Africa which we’ve successfully done over the past three years. As the need for our products and services continues to grow, we look forward to expanding our footprint as the engineered thermal solutions company for specialist industries such as EPC (Engineering Procurement Construction), Bitumen, Automotive, Power Generation, Oil and Gas, Petrochemical, Mining, Food and Beverage and Renewable Energy” Andrea concludes. eltherm South Africa (Pty) ltd Tel: (011) 326-6475 Email: info@eltherm.co.za, www.eltherm.co.za


Regional Connec

“Making Inter-state Tra

Kyalami Conference Centre, Midrand, 11 and 12 July 2018 (mornings only)

“Supply Chain Today” together with Fesarta (Federation of Eastern and Southern African Road Transport Associations) and CVLC will be running a jam-packed and informative conference across two mornings in July 2018 (11th and 12th). There will be a significant number of delegates from a wide range of African countries as well as a cross section of speakers representative of the continent.

Only Official Media Partner

Truck-X is co-located with the Fleet and MatH (Materials Handling) Expos. “Supply Chain Today” is the only official media partner of the IMHX Expo and will be covering both this Conference and the Expo in depth. Email: supplychain@promech.co.za, www.supplychaintoday.co.za Catherine Larkin, 083 300-0331

WHO SHOULD ATTEND

Regional Exporters and Importers

EXHIBITORS STANDS TO VISIT SAAFF

Freight Forwarders

FESARTA

Cross - border Transporters

Cargobond

Customs and Border Authorities

“Supply Chain Today”

Transport Associations

Loadtrac

Academics and researchers

COMESA RCTG

Cargo owners Logistics and Supply Chain Executives

COSTS

ENQUIRIES

R3 900 ex VAT - R3 200 for members

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supplychain@promech.co.za, www.supplychaintoday.co.za Catherine Larkin, 083 300-0331

VOL 68

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LUBRICATION

ctivity Conference

ansport Work in Africa”

CONFERENCE PROGRAMME DAY ONE - 11TH JULY 2018

Setting the Scene - Overview of the Programme

DAY TWO - 12TH JULY 2018

Maputo Corridor Logistics Initiative Perspective “Current Challanges and Possible Solutions for Regional Connectivity”

SADC Perspective “Tripartite Transit and Trade Facilitation Programme ( TTTFP)”

Cross-Border Road Transport Agency Perspective “Role of Transport Regulators in Promoting Seamless Road Transport Movements in the EAC-COMESA-SADC Tripartite”

North-South Corridor Persepctive “North-South Corridor Rain Pre-Feasibility Study”

Technology Perspective, Big Data in Regional Connectivity - “Need for and Use of Big Data in Regional Transport Movements”

Security Perspective “Keeping Track of Your Goods”

Operator Perspecitive “Operator Challenges in Regional Transport”

Telematics Perspective “Tracking and Tracing Cargo from Origin to Destination through Connectivity”

Transporter Perspective “Connecting Customers and Transporters through a Vitual Network”

Operator Perspective “Operator Challenges in Regional Transport”

Legal Perspective of Cross-Border Operations “ Compliance Challenges”

Customs Perspective of Cross-Border Operations “Establishment of a Private Sector Grouping in the ESA Region”

* (TBC) - to be confirmed


Why engineers are awesome To be an engineer is to be nothing less than a shaper and problem-solver of our collective future. You don’t have to sit a 5-year old down and teach her the physical and psychological benefits of building forts. Chances are she’s wrecked your lounge many times before. Written into the of our DNA is the impulse to create, to bring something that never was into being.

T

ake away the plastic weapons of mass destruction from your toy box, and watch your toddler turn his peanut butter sandwich into a gun. Beach sand becomes castles; snow days invite igloos; the world is a wonderful palette that kids just intuitively want to paint on.

It is alive and multidimensional, unleashing the power of connected societies to unlock the impossible

Essentially, the engineer is hidden inside all of us. The question for us engineers who still hold the title is, are we still living like one?

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Famous

By comparison with some of the other professions, engineering is often not seen as the “cool” one. TV shows like LA Law and Boston Legal glamourise legal eagles battling it out in high profile court cases. ER, House and Scrubs bring the world of medicine into our living rooms. Even Grand Designs puts architecture on a pedestal. Isn’t it about time that TV producers got in touch with the profession that is shaping the future world we live in like no other? As a discipline, engineering lies at the very fabric of our society, shouldering the systems and spaces that give our world its meaning. Too often the profession is associated with hard hats and tool belts, viewed as difficult and esoteric. But in reality, engineering

June 2018


letting our capes fly

is a far cry from ‘restrictive’ and ‘routine’. It is alive and multidimensional, unleashing the power of connected societies to unlock the impossible. Engineering invades every domain and asks the question, ‘how can we make this space into something fantastic?’ To be an engineer is to be nothing less than a shaper and problem-solver of our collective future.

We get to do this

Confucius said, “Choose a job you love, and you will never have to work a day in your life.” In spite of the many challenges and demands, the job of a passionate engineer should often feel like play. Every day, we get to blend new technologies into the world around us. Big data helps us gain new insight into people’s needs, which in turn fuels new design that facilitates healthy and sustainable workflows and social interactions. All the more, we are called to create new virtual reality visions of the future, which anticipate the ‘what if’s’ and puts the unknowns at ease. We get to reimagine energy as we know it and tinker with a thousand unimaginable ways to address some of the single-most important issues of our day. If we are going to remain agile and imaginative in our approach to urban co-creation and problemsolving, then engineering needs to stay fun and occasionally open to failure. If we subscribe to methodologies that resist change and reward bottom line only, we will stay too neatly within the lines.

We pen the story

Whether it be a mass transit system, a power system, a water network or a building, engineers are asking the question, ‘how will this infrastructure be relevant in the future?’ We have the privilege to keep reshaping life into systems and spaces that breed more life. Every day we are faced with the opportunity to look at issues through new lenses and improve upon historic archetypes.Good engineers steward safe boundaries. Great engineers push them wider to the benefit of society.

Game changers such as Mark Zuckerberg have altered the stakes of social engagement worldwide through Facebook’s far-reaching and immediate ability to connect people around the world. IDEO is pioneering concepts around people at the centre of design and economies of circular value. And because they have a sobering understanding of the responsibility which goes hand-in-hand with crafting community, they don’t easily back down.

We can create it!

Engineering is a constant exercise in diagnosis and treatment. We identify the pain points of society; we prescribe the remedies; and then we even get to deliver the solutions ourselves.

We are called to create new virtual reality visions of the future, which anticipate the ‘what if ’s’ and puts the unknowns at ease Every day the hand of the engineer provides enormous benefit to communities, whether that be in the form of a surgeon performing groundbreaking fibre optic treatment, or something as commonplace these days as an overseas Skype call using broadband or fibre network. Biomedical engineers are developing artificial hearts and giving amputees a new spring in their step. And leaders of science, technology and innovation are carrying the keys to unlocking poverty alleviation and meeting the basic human needs of adequate food, clean drinking water, sanitation, good health provision, shelter and education.

Step up and lead

Through tight collaboration with government, business leaders, academic institutions and the public at large, we can lead true change by painting widestroke solutions over societal problems. We carry cutting edge solutions and skills that embed the systems and smart technologies carving out our future urban ecosystems. It’s to everyone’s detriment when we fail to step up and lead. This is not a time for false humility; it’s a time to let our capes fly. Engineering is far more than a job. It’s a way of seeing the world and believing we can improve upon it. The degree to which we own our superhero status in the collective story is the degree to which we all win. www.aurecon.com

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Valves

Not just a commodity Problems with valves can lead to unplanned downtime and equivalent losses in output. This is why saving on valves can end up being expensive. With the help of Metso’s service experts, the Tarkwa mine in Ghana has been able to achieve consistent reliability, leading to improvements in the plant’s overall efficiency.

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alves play an important role in the CIL (Carbon in Leach) refining process, which Tarkwa mine adopted in 2004, both in terms of their numbers and functionality.

Premature failure has the two-fold outcome of unplanned downtime and subsequent losses in output. Metso’s Service Sales Engineer for Valves, Christian Appiah, explains that valves in the mining environment work under extremely demanding conditions. “Valve and actuator failure can arise for a number of reasons. For example, high levels of pollution owing to dust and other contaminants results in very poor air quality. “Added to this are the problems of very high ambient temperatures and pressures, not to mention the challenges posed by vibration. An erratic and low-voltage power supply also compounds potential issues,” he says.

Problems emerged

Christian goes on to explain that the valves fitted as original equipment to the secondgeneration Tarkwa plant performed as expected in terms of life expectancy, however it was after routine replacements that problems began to emerge. “There seemed to be a problem with quality, even in instances where the valves were replaced by seemingly identical products from the same brand. This is something that could be attributed to the use of lower grade materials. One of the challenges in this situation is that supply chains regard valves and similar products as commodities. Price therefore, becomes the main motivating factor behind the buying decision, irrespective of potential consequences down the line.” Metso has enjoyed a longstanding relationship with Gold Fields Ghana and it was from this association that Tarkwa was approached with regard to the possibility of sourcing alternative valve requirements from Metso’s Valves business services.

Efficiency and reliability

That was the beginning of an intensive process involving a great deal of groundwork and technical analysis over a five-year period. Christian was deeply involved in the process that ultimately provided the solution to the customer’s needs. Christian Appiah, Metso’s Service Sales Engineer for valves business

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For the Tarkwa mine, the solution was control and on/off valves, including ball, butterfly and V-port control valves that had been supplied in 2015 as replacements for items that had reached the end of their working lives.

One of the challenges in this situation is that supply chains regard valves and similar products as commodities “This was very much a team effort between technology and sales, and this level of cooperation was essential as CIL is a massive process in a plant of this magnitude. A key component in the planning phase prior to the adoption of Metso products for the CIL process was Nelprof, an advanced software solution that helped us to select the best fitting control and on-off valves for the specific application,” he adds.

Dual advantages

The dual advantages of the scientific selection and installation of valves to the correct specification and of a durable quality were soon recognized by Tarkwa Engineering management. “There has been a significant reduction in downtime and gain in productivity matched by reduced operational expenses,” notes Solomon Boateng, the Plant Engineer for Tarkwa mine - CIL.

The Tarkwa mine engineering management has been satisfied with the performance of the installed these valves as they have yielded step changes in their consistent reliability and the plant’s overall efficiency. Solomon puts the positive transition from unreliability to constant productivity into context, “These valves have now given us peace of mind concerning the operation of the critical elution circuit in the CIL process. Their use has been extended to other essential segments of our recovery processes.” www.metso.com

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Valves

AUTOMATIC SLURRY FEED SPLITTER A platinum concentrator in Rustenburg was experiencing problems with their original feed splitter in the plant keeping an equal split to the two flotation banks. eDART Slurry Valves was asked to assess the feed splitter operations and make corrective recommendations.

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ichard Rule, Director, eDart Slurry Valves says, “The mine had a simple feed splitter to two parallel rougher flotation banks. The aim was to split the feed to the two banks evenly by volume. Originally slurry was pumped from the mill discharge to the head of the flotation cells where the pipe branched off to the two flotation banks. Each branch had a flowmeter and a knife gate valve.

It will instruct one valve to close and use only the other valve in the low flow conditions The customer had to adjust the knife gate valve manually in an attempt to split the flowrate equally to each bank. The design flow rate to each bank is 540m3/h. The problem reported by the plant was that it was near impossible to keep an equal split to the two flotation banks. Firstly, any changes to the process flow or slurry density required manual adjustment of the valves. Secondly, the valves experienced excessive wear because standard knife gate valves are not suited to control applications.

Minimising pressure

“We replaced the two knife gate valves with dual external dart valves complete with positioners for

fine control. The piping layout had to be carefully considered in order to balance the upstream pressure to the two valves. Downstream of the valves we applied our experience with back pressure pipes to decouple the discharge pipe from the valve. “The valves were carefully sized to control near open to minimise additional pressure on the pump which saves operational costs for the plant,” Richard explains. “We also carried out velocity studies throughout the system in order to prevent pipe chokes and excessive wear (due to the corresponding increase in slurry velocity in those regions), after which a suitable layout, appropriate to the plant, was developed. Upon receiving customer acceptance and approval, we manufactured the new system.”

Control philosophy

The system was installed and commissioned by eDart’s site team. Two flow control loops, one for each bank, was configured in the customer’s PLC. Each of these controllers sends signals to the dart valves via the dual valve controllers. A small field mounted, low power, controller intelligently splits a single signal from the control room to the two valves. Rather than allowing two valves positioned in a high velocity, high erosive wear, close to the seat

Figure One – Analysed trendline from the control room

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The plant before the upgrade

configuration, it will instruct one valve to close and use only the other valve in the low flow conditions. The total flow into the system is measured and fifty percent of this value is used as the setpoint for the two flow controllers.

Start-up and final results

On start-up, before the control system was tuned, the flow rates were not identical. After the control system was tuned, the flow rates to each bank were very close, within 1 – 2 percentage points. (See Figure 1) Fractions of a percentage point improvements in recovery on a flotation bank translates to real money by anyone’s standards. Having accurate, precise and reliable slurry flow control equipment is one of the important foundation stones required to achieve improved recoveries. In this case, a manual flow slit between banks using an inappropriate valve for the application is replaced with automated dart valves and back pressure pipes. This will not only improve recoveries in the bank but will increase plant efficiencies due to reduced maintenance downtime. eDART Tel: (011) 823-6620 Email: sales@edart.co.za The plant after the upgrade

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Valves

Low shear control technology After more than a decade of development and testing in diverse applications, Mokveld’s Typhoon Valve System is ready for commercial use. The technology is also now available locally through Mokveld’s distributor in South Africa, Energas Technologies.

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etherlands-based Mokveld has designed and developed a low shear control valve technology that reduces shear forces significantly, following a stringent development and testing phase in accordance to DNV RP A-203. Typical applications in oil production include level control, produced water and production choke valves. Laetitia Botha, Energas Technologies product engineer, says incorporation of the low shear typhoon valve system in the design of oil production systems provides opportunities to reduce capital expenditure on field developments or increase production rates and extend the production lifetime of a mature field.

Shear forces

Emulsification and droplet breaking in petroleum phases are directly coupled to shear forces in throttling valves. The greater the shearing, the smaller the droplets and more difficult the subsequent process of separating the oil from water,” explains Laetitia.

The greater the shearing, the smaller the droplets and more difficult the subsequent process of separating the oil from water

Understanding the tech

Crude oil is seldom produced alone; the hydrocarbons are generally mixed with formation water. Some of these hydrocarbons consist of light molecules, others are heavier. The phases of the hydrocarbons depend on both pressure and temperature and may contain amounts of free hydrocarbon gas. The formation water may be produced as free water, or as an emulsion. The emulsion is a dispersion of water droplets in the oil or oil droplets in water. Separation of free water from the oil can be relatively quick, while separation of water from the emulsion is harder to accomplish due to the higher viscosity of an emulsion. Conventional valves and pumps introduce high shear forces on the liquid mixture, sometimes resulting in the formation of a more complex or tighter (smaller droplets) emulsion. The typhoon valve system is a low shear control technology developed to reduce the shear forces imposed on the mixture.

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“Shear forces are a function of the volume involved in energy dissipation in the valve. Our typhoon valve system significantly reduces shear forces by increasing the volume involved in energy dissipation by means of the axial cyclonic flow pattern through the system.”

Key benefits

The process and economic benefits of the system are multiple and proven. The key benefit is improved separation efficiency due to the low shear force technology. The Typhoon Valve System deals with the cause of the separation issues by reducing emulsification and shear forces exerted on the fluids. Due to this permanent reduction in shear, the valve has a lasting positive effect on separation, regardless of changes to the composition of the well stream over the field’s time. Meanwhile, if used as a choke valve in petroleum process streams, the system will improve the efficiency of downstream separation without resorting to chemicals or additional treatment processes.

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Typhoon Valve System

Due to cleaner production capabilities, an oil water reduction of 30-80% is achievable. Other design benefits include: • Availability – erosion resistant materials in the cyclonic flow area reduce erosion to improve operational lifetime • Accurate control – linear inherent characteristics allow optimum control for liquid level systems and flow control processes • Compact – as a result of the low actuation force requirement, small actuators can be used; combined with a compact body design this minimises the installation’s footprint

Proven capabilities

The benefits of the Typhoon Valve System have been documented during different field trails at Statoil’s Oseberg C and Troll C which resulted in full-scale technology approval qualified to TRL 6. The system installed on the Statoil operated Troll C platform controlling well fluids from the Fram Vest field. Operating in the most challenging conditions

for which the unit is designed, the system showed an impressive 60% improvement in the produced water quality (OiW) in comparison with the conventional choke valve that is installed in parallel with the unit. Combined with the previously obtained improvements of 60-90% water quality during the prototype test and the 45% improvement in water quality during the pilot test on Statoil’s operated Oseberg C platform, the fact that this patented technology reduced shear forces on dispersed liquids is unquestioned and unparalleled. Laetitia Botha Tel: (011) 397-6809 Email: laetitia@energas.co.za www.energas.co.za

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Invincible Valves (Pty) Ltd was established in 1982 and since has grown to a medium sized enterprise located in Knights, Germiston Invincible Valves prides itself on service excellent and flexibility by striving to enhance our customer’s bottom line. Our 6,500m² facility in Knights is made up of 4,500m² under roof being our stores and workshop. The facility is fully equipped to offer a one-stop resource for valves and ancillary equipment which we transport globally. As an approved BBBEE Level 4 supplier to all major industries within South Africa, we maintain expertise and experience across a broad spectrum of industries and applications with a wide range of products. We offer a comprehensive range of local and imported valves and accessories for the mining, petro-chemical, power generation, water, sewerage and general industries. We have agents in all major centres around the country and service all four corners of the globe. We offer an in-house rubber lining service for valves, pipes, fittings and vessels which is utilized by many of the country’s major valve manufacturers. In addition we offer complete service, repair and valve reconditioning services for all types of valves. Our Core Values: We believe in treating our customers with respect. We grow through creativity, invention and innovation. We integrate honesty, integrity and business ethics into all aspects of our business functioning. Our Mission Statement: Build long term relationships with our customers and clients, to provide exceptional customer services by pursuing business through innovation and advanced technology. Our Purpose: To be a leader in the Valve Industry by providing enhanced services, customer service and profitability. Our Vision: To provide a quality service that exceeds the expectations of our esteemed customers. Invincible Valves is a proud supplier of quality valve products and ancillary equipment backed by service excellence around the globe. It is the combination of these values that allows us to form lasting business relationships.

Invincible Valves (Pty) Ltd

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If it's not INVAL®, it's not Invincible 33 Shaft Road, Knights, Germiston TEL: +27 (0) 11 822 1777 | FAX: +27 (0) 11 822 3666 EMAIL: enquiries@invalve.co.za | WEB: www.invalve.co.za

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POWER TRANSMISSION

From HVAC to wine farms and mining

From wine farms to the mining industry, the new LTP-B Eco drive from SEW-Eurodrive is finding application in a range of sectors. The purpose-built drive is distinguished by the fact that different parameters can be set for a range of functions, from fan to pump control.

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hile SEW-Eurodrive does have generalpurpose units for fans, pumps, and even conveyors, it initially saw a niche for a unit specifically for the Heating, Ventilation and Air-Conditioning (HVAC) industry, targeted at building designers focusing on ‘green’ design, National Sales Manager Norman Maleka comments. In terms of a commercial building such as a hospital, traditional drives meant that fans had to operate continually at full speed. “With the improved functionality of our drive, facilities managers can now control a fan by only running it according to demand, for example. This represents a major advantage in terms of energy-saving, as it allows for total flow control,” Norman highlights.

A key focus

Although the HVAC sector remains a focus, especially in the key building-design market of Cape Town, the energy-saving benefits means it is equally applicable to customers in other niche sectors, especially as the drive is available in a broad power-output range from 0.75 kW to 250 kW. In addition, it replaces the traditional electrolytic capacitors used in the DC link with film capacitors, which have reduced energy losses, as well as eliminating the need for AC, DC or swinging chokes, which boosts the overall efficiency of the drive by 4% compared with a standard AC drive. Norman reveals that the company was recently approached by a Nelspruit customer for a 160 kW unit. “We are hoping to be able to use this as a case study, as the more real-time application data we can obtain, the more we can promote the new drive.” To date, the Cape Town branch has carried out small-scale projects relating to pumping applications for wine farms, which require mobile pumping stations. “Our customer focus on fan-and-pump applications convinced us that we needed a dedicated HVAC drive.

“Even though we can use a multipurpose drive unit, there are some limits in terms of functionality. It is always best to have a dedicated product for specific sectors, as our customers prefer customised to generic products for various applications,” Norman notes.

Raising the alarm

In terms of fan-and-pump control for mining applications, the LTP-B Eco drive is ideal to ensure clean airflow underground. HVAC control in mining operations is also highly energy-intensive, which means the new energy-efficient drive can make a significant contribution to total cost-savings.

We are hoping to be able to use this as a case study, as the more real-time application data we can obtain, the more we can promote the new drive Another benefit for mining operations in terms of enhanced health-and-safety is the drive’s fire mode, which allows for fans to run for as long as possible in the event of a fire, maximising smoke extraction and boosting evacuation time. In addition, the belt-break detection feature raises an alarm in the event of the belt slipping or any related fault occurring, in order to ensure continuous operation.

Sleep mode

Extra features include pump-cleaning and pump agitation functions, which is particularly useful if a pump has been out of operation for a period of time and needs to be restarted. The sleep mode function allows for added energy-saving when the drive is inactive. “All of these functions can be monitored directly from the drive itself, as all inputs can be fed back directly to the management system, with no direct interface required,” Norman concludes. www.sew-eurodrive.co.za

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PUMPS

Controlled-temperature test unit KSB Pumps and Valves has assisted the University of Pretoria in the construction of a large controlledtemperature test unit, which will form the backbone of ongoing research into heat transfer, fluid mechanics and thermodynamics.

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he unit will allow students to plug directly into hot, moderate or chilled liquids to use on research projects and will shave approximately 50% off students’ overall project build-up time thereby allowing more time to carry out actual research. In addition, it is expected to save considerable costs in future. Chairman of the School of Engineering and Head of Mechanical and Aeronautical Engineering, Professor Josua Meyer, says the multi-million Rand project was part-funded by the university, with donations from industrial companies such as KSB Pumps and Valves for funding, equipment and construction of the system.

Ongoing and larger-scale research projects can be undertaken, including some cutting-edge research that is already being done in collaboration with other international universities Critical studies

is conditioned through the relevant heat pumps and chilling units at near boiling or lower temperatures, as well as subzero degree Glycol at -20˚C. “The user demand within each loop is controlled using a system of pumps, variable speed drives, pressure transducers and special valves to allow up to eight experiments to plug-in simultaneously without affecting either the flow rate, working pressure or temperature of the unit. “This calls for absolute reliability and requires the best possible equipment to be used to avoid downtime that may impede any of the research programs,” adds Danie Gouws, technologist of the laboratory. “In the research laboratory, reliability is of the utmost importance and means that the university will not compromise on quality and will procure the best, most suitable equipment that money can buy.”

Etanorm pumps

About the centralised temperature-controlled unit, the Professor explains that the system relies on temperature monitoring of flow loops where water

The University specified five Etanorm 50/32/250 pump sets with 3 kW, 2.2 kW and 1.5 kW motors respectively according to flow rates, required pressure and other requirements. PLC- control ensures that all parameters are checked and balanced to ensure the system delivers fluid

Danie Gouws, technologist at the research laboratories of Mechanical and Aeronautical Engineering of the University of Pretoria

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Professor Josua Meyer, Chairman of the School of Engineering and Dylan Mitchell, Head of Mechanical and Aeronautical Engineering of the University of Pretoria

at the right temperature set points and flow conditions 24-hours per day, regardless of the number of students using the facility. It also ensures that ongoing and larger-scale research projects can be undertaken, including some cutting-edge research that is already being done in collaboration with other international universities. For example, concentrated solar power (CSP) research, nuclear safety as well as micro and power-related electronics, heat exchange tubes and clean energy studies among others are being carried out by 10 staff and 30 full time students including 10 PhD students, as well as a number of Master’s Degrees students.

Committed to education

KSB Pumps and Valves external sales representative, Dylan Mitchell, says the company was initially approached by Ascend Consulting Engineers to obtain data on the pumps. The company later revealed that a project was being undertaken for the university and that sponsorships were being sought. “In this regard we are always ready to assist educational institutions and gave the thumbs-up to the project. Wherever technical assistance was required we were happy to weigh-in with our expertise, but must commend the university, consulting engineers and the contractors who delivered a world-class installation.

Switched on

With the system up and running, Professor Meyer concludes that the project is already proving to be a great success with numerous research projects already plugged-in. “We are thankful for the ongoing support of companies. Considering heat transfer is a fundamental subject for all under-graduate engineering studies and that the University of Pretoria produces between a quarter and a third of the country’s engineers, we believe that this kind of support is essential and is a strategic investment in engineering for all of South Africa to reap the rewards.” KSB Pumps and Valves, Annett Kriel Tel: (011) 876-5600 Email: Annett.Kriel@ksb.com www.ksbpumps.co.za

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RFID TECHNOLOGY

Production of the Audi A8 It all starts with a piece of metal. In the body shop, the rear part of the vehicle represents the first stage in creating a customer’s specific order. Step by step, the car at long last starts to take shape. Once it has spent some time in the paint shop, this is the point at which even those without much interest in cars can see the individual notes that have been added – a fiery red, a deep black, or perhaps even a midnight blue.

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ut even when it isn’t being given a striking paint job, the new Audi A8 can be manufactured in numerous customisable designs to make any customer’s wish come true.

There is admittedly a long road to travel between the body shop and the new car’s first outing. Checks are required at many points along the way to ensure that the vehicle is being produced exactly as the customer had intended upon ordering. In the German city of Neckarsulm, Audi is solving this task with the help of an RFID-based identification solution that covers all the types of tasks being carried out at its plant. On the production line of the successor model to the Audi A8, launched in 2017, UHF RFID read/ write devices are hard at work. These devices reliably identify passive RFID labels on the vehicles at every step of the production process.

“Whenever we design a new production line, we naturally think about the best ways of identifying workpieces at the individual stations”, says Jan-Erik Butt, who is responsible for RFID technology at Audi in Neckarsulm. “What we really want to achieve is an identification solution that takes in every area of the plant, from the body shop to the paint shop and all the way through to the final assembly area. “The durability of RFID technology makes it ideally suited to this task. It also offers versatile connection options and can be flexibly integrated into the production system.” To compare the performance of different suppliers, Audi conducted tests in its paint shop for a whole week. It is in this location that the RFID label on the vehicle is subjected to the highest levels of stress. “We require 100 percent availability in the automotive industry, not even 90 percent is good enough for us”, emphasises Thomas Vogel, the specialist project manager in charge of digital manufacturing for the A8 model range. During the production process, the vehicles are exposed to strong external influences such as extreme heat and chemicals. Circulating air temperatures in the paint shop reach up to 230 degrees, and in the case of cathodic dip painting, the vehicle THE SOUTH AFRICAN MECHANICAL ENGINEER

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The solution that the plant was looking for needed to stand up to these harsh conditions. As a result, the project team opted for single-use passive RFID labels. These can withstand extreme stress and are easy to mount on the car body, then remove during final assembly. “The start of car body production marks the point at which a main chassis beam is inscribed and customised. It is also at this point that it receives its order number and we affix the RFID label. This is the first time that variation comes into play, and we use this for identification purposes. From then on, we always have RFID features on the vehicle.”

Assembly process

Maximum availability

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It is at this stage in the process that a voltage is applied and the metal is coated with anti-corrosion treatment, explains Jan-Erik Butt.

The RFID label is about the same size as a business card and is made from Nomex material, which protects the antenna inside and the chip against heat and other influences.

To compare the performance of different suppliers, Audi conducted tests in its paint shop for a whole week

Challenging environments

is entirely immersed in a tank containing an acid/ base mixture.

The changes that take place between one customised vehicle and another being built are usually found in the assembly process, and are dictated by the design that the customer has ordered. There is a very high level of variation at this stage and it is therefore essential that vehicles are correctly identified. Ultimately, each employee must know which vehicle they have in front of them in order to customise it as appropriate. Also, Audi has opted for a specific type of concept that makes it even more important for the RFID solution to perform reliably. The RFID reading process is linked to a belt stop, which means that the production line will come to a standstill if RFID identification of a vehicle fails at any given point. In this way, Audi can ensure that no vehicle leaves a station without having been identified. The RFID label is eventually removed during final assembly, sometimes on account of the sensitive production data it is associated with.

Standardised data overview

For Jan-Erik, another reason for relying on RFID is the consistently high standard of data quality delivered by the readings at every station. “If we acquire the same type of data from every area, we can generate informative trend analyses, for example. This is because the reading situations can be compared with one another. As a result, we are able to obtain extensive information on the entire

June 2018


production process, something that just wouldn’t be achievable if we were using a mixed bag of technology. “This naturally gives us the opportunity to take an entirely different approach, to put preventive measures in place rather than simply responding to situations all the time. For example, we are working on methods of observing how reading quality gradually deteriorates in order to intervene before problems occur.”

Specific applications

As part of its RFID solution, the Audi site in Neckarsulm is using the Sick AppSpace eco-system, which allows tailor-made sensor apps to be programmed with ease. “We want to harness new ways of processing data further, exactly in line with our needs. For example, we are implementing Sick AppSpace at reading points in order to allow the antenna to communicate directly with the MES system that we use to control production, and to do so in the appropriate format for the recipient.

At its Neckarsulm plant, Audi is relying on an RFID-based identification solution that covers all the tasks being carried out at every stage of production.

“Without the need for any additional middleware, we are able to create a service-based architectural framework, such as OPC UA, that is not reliant on any particular platform or manufacturer. “This means that we don’t have to change all the system settings each time reprogramming takes place. Instead, we can use an app to remotely determine how the antenna is to process and transfer data. We want the ability to operate a whole range of different functions flexibly within a single reading device. It therefore makes sense to use an antenna that is more intelligent too,” Jan-Erik explains.

Overarching identification strategy

Summing up, he has a positive view of how things have progressed,“If we compare the situation before and after, we can see that the successful switch to the new technology has led to an increase in availability and even significant time savings in many cases. In contrast to the original proprietary systems, commissioning RFID antennas is less time-consuming.”

Reliable identification of passive RFID labels on the vehicles

What started as part of a vehicle project, and was designed for a specific item derived from another product, has now been up and running throughout the plant for some time now. “The results we have gained from the RFID identification process have won us over. Instead of RFID only being used in a single hall or as part of a single vehicle project, the Neckarsulm site is using it for identification purposes at every stage of production.” Mark Madeley Sick Automation Southern Africa (Pty) Ltd. Tel: (100) 600-0550, Cell: 082 454-9904 Email: Mark.Madeley@sickautomation.co.za www.sickautomation.co.za

Intelligent identification with RFID

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THREE LETTERS. TOTAL QUALITY. NSK sets many things in motion – for example in the industrial gearbox industry. As a leading global manufacturer of rolling bearings, NSK combines 100 years of success and a total quality approach.

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www.nskeurope.com nsk-sa@nsk.com


SOFTWARE

Functioning as a team When different departments within a manufacturing business operate independently, it makes it difficult to share relevant information, which makes it easier to get blindsided by competitors with a smarter game plan.

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he SAP Business One Manufacturing software solution has been tailored specifically for small to medium sized businesses within this highly competitive industry. Light manufacturing, make-to-order (MTO), engineer to order (ETO), mixed-mode, and assembly focused businesses can all get ahead of the game with an integrated mid-market Enterprise Resource Planning (ERP) system.

their entire manufacturing process, from production scheduling through to purchasing and logistics. It is designed to help manage material requirements planning (MRP) for multi-level production processes, create resource planning scenarios to forecast demand and generate automatic replenishment orders to prevent material shortages.

Contrary to paper-based picking systems, stock can be scanned out and the information is quickly passed through to other departments for required checks, reducing the risk of human error, which protects margins. This reduces the time needed for manual stock Another revaluation.

“It is ideal for companies which engage primarily in light manufacturing or lack the internal capacity for advanced manufacturing systems. It is easy to configure with existing applications and has room benefit is the for customisation.” says complete customer Craig Johnston, Marketing Manager at Bluekey view it offers across Seidor. The package includes standard SAP Business One features as well as specific manufacturing features such as: • Lot, batch and serial control

sales, distribution and financials

• project cost tracking • labour management • multi-level bill of materials • forecasting • multi-warehouse management capability • extensive item master management

Protecting margins

The system will assist businesses in streamlining

The ability to track inventory levels in real-time means that inventory is optimised, which gives companies the advantage to reduce inventory-carrying cost while minimising the risk of stock outages.

Another benefit is the complete customer view it offers across sales, distribution and financials. “This will certainly help businesses with their customer retention and identify opportunities to expand. Managers can keep their eye on the ball and will have less chance of getting penalised because someone forgot to, for example, save details of the last communication with a customer,” Craig concludes www.bluekeyseidor.com

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BIOLOGICAL TREATMENT

Recycling Waste Water the Key Could it be that recycling water is the key to water availability relief for the Cape region, as opposed to imposing increasingly stricter and potentially unviable water usage restrictions as well as costly desalination?

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ewTreat have put forward another option, the biological treatment and recycling of waste water.

being supplied to us. In addition there has been a stigma around drinking or re-using treated and recycled sewage water.

SewTreat spokesperson, Theunis Coetzer, says that water restrictions ultimately still result in wastage. “Even if we restrict use to 25 litres per person per day, this water is still destined to go down the drain and be gone forever. What if we could recycle this back into clean, safe drinking water?” he asks.

“What businesses, schools and hospitals will start to realise is that recycling water by means of natural, eco-friendly, biological treatment methods is the best and most cost-effective way to ensure water availability and security,” Theunis explains.

“In the past, the cost of the infrastructure required and the fact that we had cost-effective water supply, prevented the technology from taking root, but modular plant designs using biological treatment methods are changing the game.”

Stigma

Treating sewage water and waste water for re-use is by no means a new concept but previously the methods used and the infrastructure construction needed to implement water recycling have made it a wonderful ‘green’ dream that no-one could financially realise. “We have also had relatively cost-effective water

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While the concept was unthinkable in a South African setting two years ago, it has been successfully done in numerous countries around the world for years. In 2014, three years into California’s worst drought in over a century, the state’s Orange County Water District (OCWD), established a pioneering waste water treatment facility that recycles used water, or sewage, and returns it to the drinking supply. The plant’s production expanded from 259 to 370 million litres per day.

Namibia

Closer to home, Windhoek has been successfully treating waste water to drinking standards for the past 50 years. Most of the waste water produced by Windhoek’s 300 000 residents is sent to the

June 2018


Goreangab waste treatment plant, the first stop in the city’s pioneering water recycling system. The systems and technology have more than proven themselves and, far from being repulsed by the idea of drinking recycled sewage water, the residents have no complaints and are in fact proud of what they have achieved with the plant. Businesses, organisations, residential estates, schools, retirement homes, retail spaces, farms and communities will likely be pursuing the installation of modular, biological waste water treatment plants in the years ahead because these systems can be implemented very quickly and at an affordable price. In fact, the price comparison between re-cycling used and sewage water and desalination is staggering. The cost factor is based around the highly concentrated waste (brine) and high electrical energy requirements for desalination that make it more expensive in terms of Rand per litre for the final drinkable water.

Home to business

SewTreat offers specialised, modular biological waste water treatment plant designs tailor-made for the South African and African market. Their approach is based on return activated sludge technology incorporating submersed aeration media. This enhanced bacterial action ensures a highly effective treatment process boasting a very low

carbon footprint, minimal capital input and low maintenance requirements. Their product offering includes modular fibre glass waste water treatment plants that can be installed either above or below ground for any operation from home use to medium sized business operations. Tailor-made for homeowners and lodges, the company also offers DIY plants that are cost effective and easy to install.

Treating sewage water and waste water for re-use is by no means a new concept but previously the methods used and the infrastructure construction needed to implement water recycling have made it a wonderful ‘green’ dream that no-one could financially realise For larger business operations and firms within the industrial sectors, the company offers Mega and Civil Constructed waste water treatment plants. “It is 100% possible to recycle both sewage and waste water to the point that it is safe for drinking. We are facing a major water crisis of epic proportions and it is time to recognise this process for the major contribution that it can make to water security,” Theunis concludes. www.sewtreat.co.za

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The Local Manufacturing Expo Aims to:

21 – 23 MAY 2019

Promote local manufacturing

EXPO CENTRE, NASREC,

Demonstrate Southern Africa’s export potential

JOHANNESBURG, SOUTH AFRICA

Provide access to global markets

A Showcase of Southern Africa’s Manufacturing Capabilities Who Will Exhibit?

Networking opportunities Develop public / private partnerships Public / private sector collaborations Identify industry challenges and opportunities for growth

Manufacturers across a variety of sectors, including:

Agriprocessing

Automotive

Business Process Outsourcing

Capital Equipment

Chemicals

Construction

Engineering

Food and Beverage

Furniture

ICT and Electronics

Metals

Mining

Plastics

Textiles/ Clothing/ Footwear

Transport

www.localmanufacturingexpo.co.za In association with:

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Endorsed by:

THE SOUTH AFRICAN MECHANICAL ENGINEER

Implemented by:

VOL 68

June 2018

Brought to you by:


Making tailings a valuable product Weir Minerals has announced their long term strategic cooperation agreement with International technology group Andritz to supply equipment for processing tailings in the mining industry. s part of this agreement, Andritz will supply proven separation and dewatering technologies, thus enabling Weir Minerals to offer complete tailings solutions to its customers.

A

In 2016, Weir Minerals opened the Weir Technical Centre, which has enhanced the company’s global tailings offering by developing and testing pipeline and tailings solutions as well as manufacturing specific tailings-based products.

“The tailings market is experiencing growth driven by environmental and governmental pressures. We understand our customers are under increased pressure to further improve the management of their mine tailings, which is why we have partnered with Andritz, states Ricardo Garib, Weir Minerals Division President.

Ricardo highlights, “This latest agreement complements our overall tailings offering and enables us to provide our customers with a complete tailings solution. Under the brand name IsoDry, we will now offer customers a range of mechanical separation technologies, such as thickeners, filter presses, centrifuges, and vacuum belt filters.”

“We are industry leaders in mineral processing equipment, with well known brands such as Warman, Geho and Cavex, all of which are backed by our global service footprint. Our capabilities, teamed with Andritz extensive knowledge on tailings thickening, will ensure our customers receive a complete tailings solution.” “Our separation technologies have been proven in a large number of industries, such as food and beverage production, chemicals, biomass, organic waste, and mining. We are proud to work with Weir Minerals, who operate in over 70 countries worldwide and in the most remote locations, and to contribute to their offering of sustainable and value-added tailings solutions with our expertise and product know-how,” adds Olaf Müller, Business Area Manager of Andritz Separation.

Specific products

For a number of decades, Weir Minerals has provided mines around the world with sustainable and cost-effective solutions for the management, disposal, and recycling of mine waste. The Geho positive displacement pumps transport ores, minerals, and tailings under extreme conditions, while minimising both water and energy consumption at the same time.

The process is safer than alternative solutions and better for the environment, allowing for improved recovery of process chemicals and giving back clean water. Dry tailings

Dry stack deposition removes harmful waste byproducts to create a compacted dry cake that can be disposed of safely. The process is safer than alternative solutions and better for the environment, allowing for improved recovery of process chemicals and giving back clean water. Weir Minerals take their solutions offering one step further by providing sustainable management that sees tailings converted into effective products, reducing costs as well as risks for operators. “Dry stacking of tailings is achieved by using a combination of belt, drum, stacked pressure plates, and vacuum filtration systems. We are thrilled that we can now offer this option to our customers and optimise the performance and efficiency of their tailings process. “Our unique ability to specify the manufacture and transport of backfill products from tailings and the recovery of water from tailings slurries can significantly help our customers reduce costs and risks,” Ricardo concludes. Marielle Kossen, Head of Marketing WEIR MINERALS, marielle.kossen@mail.weir

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MARKET FORUM

Packaged Water Treatment Plants

Veolia Water Technologies South Africa recently assisted state-owned hospital, Bambisana, with two packaged water treatment plants. Situated in the remote Eastern Cape, the hospital required lowfootprint and low-maintenance water treatment solutions to provide potable water to the hospital as well as to treat its sewage water for re-use.

supply of water and was therefore unsuitable for the hospital that requires consistent, high-quality water for its day-to-day operations. “Furthermore, our water quality studies indicated that the existing reservoir and borehole water was host to low-concentration bacteria, high turbidity and slight residual colouring,” comments Royston.

Veolia designed, manufactured and commissioned two of its trademarked containerised, plug-and-play solutions in just three months for the hospital.

Veolia supplied the hospital with its Potable Water Treatment Plant (PWTP) that produces 120m3 of high-quality potable water per day. The PWTP features a clarifier, sand filter, carbon filter and a range of chlorine, coagulant, flocculant and pH dosing equipment, all packaged in a single container to treat the water to SANS241 and WHO standards.

“Our packaged plant solutions are a costeffective alternative to in-ground plants and are well suited for remote areas that are situated away from bulk water infrastructure, such as with Bambisana hospital,” says Royston Moses, Project Engineer at Veolia. The previous reservoir infrastructure provided an inconsistent

With no former sewage treatment infrastructure in place, the hospital also required a packaged plant to treat its

The sewage treatment plant makes the community’s wastewater re-use possible

wastewater according to the RSA General Standard for Discharge. Veolia addressed this with its packaged Sewage Treatment Plant (STP) that upgrades 60m3 of sewage water per day. Enclosed in 6 six-metre containers, the STP features Veolia’s cost-effective trickling filter technology to treat the sewage water to certified re-use standards, as well as a bar screen, septic tanks, clarifiers and chlorine-dosing equipment. This treated water is now re-used by the community for irrigation and agricultural purposes. Veolia Water Technologies South Africa Royston Moses, Tel: (021) 870-2705 Email: royston.moses@veolia.com www.veoliawatertechnologies.co.za Mining Food and Beverage Oil and Petrochemical Chemical Water / Wastewater Pharmaceutical Industrial ©CM 270418MF

A pump solution for every application

Verder Pumps SA (Pty) Ltd

Tel: +27 (0)11 704 7500

info@verder.co.za

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OP TIMAL ENERGY SOLUTIONS “Our solutions are not off-the-shelf, and are tailor made for individual application requirements,” says Alastair Gerrard of Zest. “Our team spends time gaining an in-depth understanding of what the customer really needs, and the operational constraints. During this process, we collaborate with reliable, in-country partners who have local knowledge and experience. This local presence also facilitates quick response times and 24/7 after-sales support.”

Zest WEG Group also offers a standard off- centres (MCCs), containerised electrical solutions and E-houses. the-shelf range of gen sets. Forming part of Zest WEG Group’s manufacturing operations in South Africa is WEG Transformers Africa which has two facilities capable of producing transformers up to 45 MVA/132 kV and a range of mini substations up to 33 kV. Also part of the group is Shaw Controls which is a leading local manufacturer of custom electrical panels, motor control

E-houses have become popular in Africa as these are pre-assembled and tested in a factory prior to being transported to site by truck. Zest Weg Group Africa Tel: (011) 723-6000 Email: marketing@zestweg.com www.zestweg.com

Alastair emphasises the use of parent company, WEG’s range of motors, variable speed drives and soft starters, as well as its low voltage and medium voltage switchgear. These products are an integral part of the fit-for-purpose solutions, as is Zest WEG Group’s South African manufacturing capability in terms of generator sets, transformers, substations and other mobile energy solutions. “Operating a local gen set manufacturing facility staffed by experienced engineers allows us the flexibility to package this offering with an engine and alternator combination to suit the customer preference,” he adds.

Increasing Safety

lation of these products. Firstly, does the product comply with the requisite SABS standards? Secondly, does the supplier manufacture products in accordance with ISO quality standards? Another telling factor is if, on visual inspection, there are cracks between the knuckles or if the strands appear too thin,” Lance advises.

On-site safety remains a major focus for all industries. While slips, trips and falls can be attributed to a number of factors, inadequately designed and manufactured walkways remain a primary contributor to on-site accidents. According to Lance Quinlan, national technical sales consultant at Andrew Mentis, organisations need to make it their business to determine whether the walkway products they are using are manufactured from high quality, application-specific material. “The same level of emphasis on safety also applies to the use of expanded metal for guardrails and protection cages, filter

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and machine motor covers, lift side walls and ladder rungs. “There are questions one should ask of an expanded metal supplier before committing to the instal-

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He explains that Andrew Mentis regularly submits expanded metal samples to the SABS while their manufacturing facility is audited every six months to maintain current certification to verify that their expanded metal products meet the criteria for shortway, thickness and bendability. Andrew Mentis, Lance Quinlan Tel: (011) 255-3200 www.mentis.co.za


MARKET FORUM

Stainless Steel Pumps With the increased levels of acidity in mine water and associated slurry handling applications, Integrated Pump Technology has reported an increased demand for its Faggiolati stainless steel slurry pump. Constructed from 316 stainless steel, the Faggiolati pump is engineered to operate in the toughest applications dealing with the handling of corrosive water and sludges. “In all dewatering applications, whether in underground mine shafts, mine waste dumps, ore stockpiles, tailings facilities or power stations, reliability remains a key requirement, and there is no doubt that a stainless steel pump is by far the best choice for use in acidic environment,� Colin Adams, managing director of Integrated Pump Technology, says. The excellent corrosion resistant properties of stainless steel ensure reliable operation even under the harshest conditions. By eliminating the risk of corrosion in pumps, unscheduled downtime is dramatically reduced and the risk of pump failure is averted. Faggiolati stainless steel pumps are able to withstand highly acidic water, even when it contains high concentrations of metals and sulphates. The pumps are also capable of handling abrasive particles and a high content of solids up to the size of the pump inlet diameter opening. The cast stainless steel impeller ensures pumping capacities in the corrosive fluids and can handle pH values from two to 10. The most recent order received by Integrated Pump Technology was for six Faggiolati stainless steel channel pumps, and Colin says the pumps will be operating in an extremely acidic environment at a power utility. Integrated Pump Technology Email: colin@pumptechnology.com www.pumptechnology.com

www.pumprental.co.za

ring e t a w e d k c o l c e h t roundTHE SOUTH AFRICAN MECHANICAL ENGINEER

tel: +27 11 894 2906 email: admin@pumprental.co.za

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Julian Desmore has been appointed Sales Manager at Hytec Cape Town

MAKE SURE YOU VISIT THE PROMECH PUBLISHING STAND AT ELECTRA MINING 2018

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THE SOUTH AFRICAN MECHANICAL ENGINEER

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