14 minute read
Proof load test water bags
The age-old question within the lifting industry is the use of solid weights VS proof load test water bags.
While there is use for both solid weights & water bags in the industry depending on the applications and site requirements, water bags are the more economical option when it comes to the inspection and load testing of larger lifting machinery. Some machines such as forklifts are only suited to testing with a solid test weight as the machine's load centre needs to be achieved and the test load cannot be under-slung as per SANS 10388. While there is use for both solid weights & water bags in the industry depending on the applications and site requirements - water bags are the more economical option. So the debate begins. Test weights or proof load test water bags?
Cost-saving
It is far more economical to transport water bags as opposed to solid test weights provided the application is right. As mentioned – forklifts and certain other machinery cannot be tested with water bags. If we look at the practicality with regards to the transportation – water bags make more sense.
As a frame of reference to transport 70 tons of solid test weights will likely require three trucks and the logistical cost on that is astronomical, whereas the transportation of 70 tons of water bags is simple - 2x correctly rolled 35-ton proof load test bags can be transported on a 1-ton light delivery vehicle or bakkie as we put it in South Africa. This means that we can achieve more competitive pricing as the logistic cost is lowered.
Going green.
Now we know to be more conscious than ever when it comes to environmental issues and water saving methods. So how do we combat this?Simple – most sites have water treatment systems and we can pump the water back into the system to avoid wastage. With regards to port applications – seawater can be pumped from the port – provided the right pumps are used and the seawater is drained straight back into the ocean.
Use of flow meters VS load cells
While a flow meter is a cheaper option - one must take into account the function of a flow meter, which is to measure flow and not mass. Many factors could affect the reading of the flow meter for load test use. One factor is the viscosity of the water – basically the water density. Are you using clean water, dirty water or seawater? All factors play a role in the mass that will be applied. Now a flow meter only measures flow and not water density and therefore cannot be considered accurate. Another factor that could affect the reading of the flow meter is if the water is not clean and an object becomes jammed – such as a stone – the water will keep flowing and the load will increase – however the reading on the flow meter will not. If we look at Europe – Flow meters are no longer permitted to be used as there have been multiple incidents that have occurred whilst in use.
The function of a load cell is to measure mass or load and is, therefore, more suited to the application of load testing. One must remember it is essential for a load cell to be calibrated regularly to ensure accuracy.
Now let's talk price.
The cost of water bags are very high as the materials used must be of the highest quality.The investment in water bags requires a lot of capital to procure these bags and the life spans depend on care, handling, frequency of use and material construction. Regular maintenance is also essential. It is not economical for some companies to purchase bags due to the capital required, however -there are a few companies such as ours - that offer water bag rentals and will gladly assist throughout Africa with rental solutions to suit the project.
The rigging of Load Test bags.
LMI's & LME's making use of load test bags must know how to rig them. It is also essential to note that the way bags are rigged could effect tonnage capacities if multiple bags are rigged together. The way bags are rigged could
also affect the loss of water on the ground and drainage of the bags. As a rule of thumb when calculating how many bags need to be used on larger tests – we often allow for +/- 10% in loss of capacity per bag – provided the bags are rigged correctly.
Not shock loading.
Use of water bags also avoids the machine being shock loaded and avoids damaging the machine further should the crane have a failure.
This is because the load is increased in increments by filling water the LMI can monitor the machine as the load is increased – if any defection is detected the LMI can stop filling the bag and drain to avoid failure. This safety aspect is essential – as it avoids further damage to the lifting machine and machinery surrounding the machine. Quality and material construction of proof load test bags are essential as they are required to simulate large load tonnages, and any failure due to poor quality products could result in catastrophic failure onsite in which you are working and this risk must be nullified. How do we do this? By ensuring that the bags which are used are of the highest quality and conform to international standards. Multiple incidents have occurred within South Africa and around the world as a result of using bags that are of inferior quality. A few years back an incident occurred within South Africa and an investigation was carried out by CSIR. CSIR documented every aspect of the material construction did a comparison between the bag that failed and a European proof load test bag from our company. It was found that the material construction was far inferior on the failing bag - and the material construction in terms of thickness was documented as 0,6mm, the mass/unit area was documented at 880g/m2, tensile strength was documented at 3000/3200*N, further to this puncture tolerance was found to not have any tolerance.
CSIR found the material used to be suitable for industrial tarpaulins. We have also seen this on some other imported bags. The material is also of much inferior quality and often the slings used for the harnesses are not lifting slings but rather a sort of lashing material.
QUALITY PROOF LOAD TEST BAGS IS ESSENTIAL
Just as a comparison – our bag that was also subjected to the testing at CSIR – it was documented that the thickness of the bag was 1,3mm thick, the mass/unit area was 1650/m2, tensile strength was 8300/9800*N, further to this our bag was found to have a puncture tolerance.
This means that if the bag is punctured – the bag will not split and water will just come out from the puncture – but will not drop an entire load of water onto the floor. The CSIR found the material used to be suitable for airlift bags for which
they were originally designed and suitable material for proof load test bags. The standards that should be adhered to are as follows when looking at proof load test bags – EN ISO 1421, DIN 53357, DIN 53358, DIN EN 12127, DIN EN 1876. Other quality assurance testing that should be done are tests such as drop tests whereby certificates are issued to assure the quality of the bag.Most European bags come with this certification. This essentially means - the bag is filled within its rated capacity and a drop test is conducted – to put this into perspective because the force of the drop test on a 20-ton proof load test water bag is simulated to 44 tons – this test is conducted on every bag before it is sent out and not one per batch – this test is done only on commissioning. This is essential to ensuring the quality of the bags. In conclusion, it is more economical to use proof load test bags to test lifting machinery provided the application permit this. We also strongly advise the use of load cells with the use of water bags rather than a flow meter.
World Wide Load Testing Specialists,
BEAM CRAWLS & BEAM CLAMPS
Elephant Lifting Equipment T: +27 (0) 12 661-6105 F: +27 (0) 12 661-6104 E: info@elephantlifting.co.za W: www.elephantlifting.co.za
BLOCKS
Toco Lifting T: +27 (0) 11 345-8800 E: toco@toco.co.za W: www.tocolifting.co.za
Condra Cranes T: +27 (0) 11 776 6000 E: sales@condra.co.za W: www.condra.co.za
CRANE HIRE FORKLIFTS
Kemach JCB T: +27 (0) 11 826-6710 E: info@kemachjcb.co.za W: www.kemachjcb.co.za
Jungheinrich T: +27 (0) 10 596-8460 E: info@jungheinrich.co.za W: www.jungheinrich.co.za
XCMG, T: 0086 135 8547 4543, E: rsa@xcmg.com, W: www.xcmg.com
HOISTS
New Height Lifting T: +27 (0) 82 304 9814 E: lolita@newheight.com W: www.newleight.com
Marlboro Crane Hire T: +27 (0) 11 882-8301/2 F: +27 (0) 11 882-8303 E: hire@marlborocrane.co.za W: www.marlborocrane.co.za
CRAWLER CRANES
Liebherr T: +27 (0) 11 365-2000 E: info.laf@liebherr.com W: www.liebherr.com
EQUIPMENT HIRE
Yale Lifting Solutions T: +27 (0) 11 794-2910 F: +27 (0) 11 794-3560 E: crm@yalelift.co.za W: www.yale.co.za
Morris Material Handling SA T: +27 (0) 11 748-1000 F: +27 (0) 11 748-1093 E: sales@morris.co.za W: www.morris.co.za
World Wide Load Testing Specialist T: +27 (0) 31 572-4940 E: ops@wwlts.co.za W: www.wwlts.co.za
Yale Lifting Solutions T: +27 (0) 11 794-2910 F: +27 (0) 11 794-3560 E: crm@yalelift.co.za W: www.yale.co.za
HOSE AND CABLE REELS
DEMAC SRL T: +39 02-9784488 F: +39 02-97003509 E: info@demac.it W: www.demac.it
HYDRAULIC TOOLS
Kiloton T: +27 (0) 861 707-707 F: +27 (0) 861 707-706 E: sales@kiloton.co.za W: www.kiloton.co.za W: www.onlinetoolshop.kiloton.co.za
INSPECTION
Load Testing & Inspection Specialists
Cranemec Group S.A T: +27 (0) 16 366-1393 F: +27 (0) 16 366-1392 E: info@cranemec.co.za W: www.cranemec.co.za
Knuckle Boom
XCMG, T: 0086 135 8547 4543, E: rsa@xcmg.com, W: www.xcmg.com
LIFTING TACKLE
AJ Cranes T: +27 (0) 78 599-0610 E: hannes@ajcranes.co.za W: www.ajcranes.co.za
MH Dawood Plant Services T: +27 (0) 11 496-1007 F: +27 (0) 11 496-1198 E: info@mhdawood.co.za W: www.mhdawood.co.za
Scaw Metals SA T: +27 (0) 11 601-8400 F: +27 (0) 11 601-8405 E: wbyleveldt@scaw.co.za W: www.scaw.co.za
CB Lifting Equipment T: +27 (0) 11 023-5414/5 (JHB) T: +27 (0) 22 719-1435 (CPT) E: info@cblifting.co.za W: www.cblifting.co.za
EnerMech T: +27 (0) 21 286-4035 F: +27 (0) 21 511-3553 E: gstuart@enermech.com W: www.enermech.com
C: +27 (0) 72 043-4018
E: savannahm@premierload.co.za W: www.premierload.co.za Yale Lifting Solutions T: +27 (0) 11 794-2910 F: +27 (0) 11 794-3560 E: crm@yalelift.co.za W: www.yale.co.za
LOAD TESTING AND RE-CERTIFICATION
AJ Cranes T: +27 (0) 78 599-0610 E: hannes@ajcranes.co.za W: www.ajcranes.co.za
GregBev Enterprise C: +27 (0) 82 854-5143 C: +27 (0) 72 395 4342 E: info@gregbev.co.za W: www.gregbev.co.za
Loadtech T: +27 (0) 12 661-0830 C: +27 (0) 82 774-5223 E: glen@loadtech.co.za W: www.loadtech.co.za
MOBILE CRANES
COTAC Oy T: +35 840 069-9469 F: +35 842 016-6959 E: office@crane.fi W: www.crane.fi
C: +27 (0) 72 043-4018
E: savannahm@premierload.co.za W: www.premierload.co.za
XCMG, T: 0086 135 8547 4543, E: rsa@xcmg.com, W: www.xcmg.com By Carpel SRL - Italy T: + 39 (0) 39 532-0952 F: + 39 (0) 39 532-0825 E: info@bycarpel.it W: www.bycarpel.it
Demag Cranes T: +27 (0) 11 898-3500 F: +27 (0) 11 898-3533 E: richard.roughly@demag- cranes.com W: www.demagcranes.co.za
REPAIRS
AJ Cranes T: +27 (0) 78 599-0610 E: hannes@ajcranes.co.za W: www.ajcranes.co.za
J Express Crane Services T: +27 (0) 11 864-8402 F: +27 (0) 11 864-8408 M: +27 (0) 83 425-5535 E: jexpress@telkomsa.net
Yale Lifting Solutions T: +27 (0) 11 794-2910 F: +27 (0) 11 794-3560 E: crm@yalelift.co.za W: www.yale.co.za
MAINTENANCE
Liebherr T: +27 (0) 11 365-2000 E: info.laf@liebherr.com W: www.liebherr.com
MOBILE CRANE SPARES
Insu Tech Corporation T: +91-866 999 7733 T: +91-866 999 7833 E: info@insutech.net W: www.insutech.net
C: +27 (0) 72 043-4018
E: savannahm@premierload.co.za W: www.premierload.co.za
Jekko s.r.l. T: +39 0438 1410083 F: +39 0438 1710123 E: info@jekko.it W: www.jekko-cranes.com Cranemec Group S.A T: +27 (0) 16 366-1393 F: +27 (0) 16 366-1392 E: info@cranemec.co.za W: www.cranemec.co.za
Liebherr T: +27 (0) 11 365-2000 E: info.laf@liebherr.com W: www.liebherr.com
OVERHEAD CRANE
AJM Engineering T: +27 (0) 11 453-0728 E: info@ajmengineering.co.za W: www.ajmengineering.co.za
Condra Cranes T: +27 (0) 11 776 6000 E: sales@condra.co.za W: www.condra.co.za HP Cranes Consulting T: +27 (0) 11 740-9725/28 E: donavan@hpcranes.co.za W: www.hpcranes.co.za
IY Safety T: +27 (0) 82 773-7019 C: +27 (0) 82 956-3176 E: bianca@iysafetyinspection. co.za W: www.iysafetyinspection.com
Konecranes T: +27 (0) 11 898-3500 F: +27 (0) 11 898-3533 E: john.macdonald@konecranes. com W: www.konecranes.co.za New Height Lifting T: +27 (0) 82 304 9814 E: lolita@newheight.com W: www.newleight.com
SLINGS
Andromeda Industries T: +61 (0) 2 6760 3773 M: +61 (0) 448 668 308 E: zelman@andromesaindustries. com.au W: www.wireropesling.com.au
Scaw Metals SA T: +27 (0) 11 601-8400 F: +27 (0) 11 601-8405 E: wbyleveldt@scaw.co.za W: www.scaw.co.za
SPIDER CRANES
Morris Material Handling SA T: +27 (0) 11 748-1000 F: +27 (0) 11 748-1093 E: sales@morris.co.za W: www.morris.co.za XCMG, T: 0086 135 8547 4543, E: rsa@xcmg.com, W: www.xcmg.com
Yale Lifting Solutions T: +27 (0) 11 794-2910 F: +27 (0) 11 794-3560 E: crm@yalelift.co.za W: www.yale.co.za Jekko s.r.l. T: +39 0438 1410083 F: +39 0438 1710123 E: info@jekko.it W: www.jekko-cranes.com
STEEL WIRE ROPES
New Height Lifting T: +27 (0) 82 304 9814 E: lolita@newheight.com W: www.newleight.com
TRAINING
Artisan Training Institute T: +27 (0) 11 022 0100 T: +27 (0) 11 475 3443 F: +27 (0) 11 672 3888 W: www.artisantraining.co.za
Scaw Metals SA T: +27 (0) 11 601-8400 F: +27 (0) 11 601-8405 E: wbyleveldt@scaw.co.za W: www.scaw.co.za
STRADDLE CARRIER
Combi Lift T: +27 (0) 11 900-8010 E: victor@solutions-4u.co.za W: www.combilift.co.za
TESTING
Cranemec Group S.A T: +27 (0) 16 366-1393 F: +27 (0) 16 366-1392 E: info@cranemec.co.za W: www.cranemec.co.za
Global Training T: +27 (0) 86 999-0843 E: info@globaltraining.co.za W: www.globaltraining.co.za
LMI Academy T: +27 (0) 11 475-5876 E: info@lmi-academy.co.za W: www.lmi-academy.co.za
CJH Cranes Equipment & Plant T: +27 (0) 11 963-0670 E: info@cjhcranes.co.za F: +27 (0) 86 619-7755 W: www.cjhcranes.co.za
TOWER CRANES
Liebherr T: +27 (0) 11 365-2000 E: info.laf@liebherr.com W: www.liebherr.com
Phakamisa Safety Consultants T: +27 (0) 11 462-9620/1 F: +27 (0) 11 462-9620 E: potto@icon.co.za W: www.phakamisasafety.co.za
WATER WEIGHT BAGS
DOOWIN Water Bags T: +86-532-87788178
M: +86-185 5486 9267
E: sales@doowin-dooflex.com W: www.doowincn.com
MH Dawood Plant Services T: +27 (0) 11 496-1007 F: +27 (0) 11 496-1198 E: info@mhdawood.co.za W: www.mhdawood.co.za
WINCHES
Dymot Engineering T: +27 (0) 11 970-1920 F: +27 (0) 11 970-1979 E: pa@dymot.co.za W: www.dymot.co.za
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