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Does It Really Matter

Cargo Control for Tow Professionals

Cargo Control for Tow Professionals

B/A products has been manufacturing and distributing towing and recovery products since 1978. We have come a long way since our start, increasing our product line, doing more manufacturing in house, larger space and more employees. Product quality is our top priority, and to ensure quality, we do a lot of testing.

If you have been to one of our open houses, you may have seen some of the testing we do. Random samples of all inbound chain, wire rope and forgings, snatch blocks and more are tested. While we receive documentation from our manufacturers, we test to verify that documentation. Does it matter? Yes!

In the course of testing, we occasionally find product that does not meet our specifications. We received a batch of chain that was not breaking properly. While the chain made minimum break strength, there was little to no elongation, the chain was too brittle. After discussing the problem with the chain manufacturer, it was discovered the chain had been heat treated to the wrong specification. The chain was returned, annealed and reheat treated, and now met spec. Did it really matter? In this case, yes.

We also test finished product to verify that the ratings we give them are accurate. When we started making tie downs for the auto hauling industry, there was a lot of debate on what the Work Load Limit of the straps should be. One side wanted to rate it based on the weakest component. The other side said in use, the load would be distributed and it would withstand a higher load. How to settle the debate? We built a mock up of a car hauler deck to use on our Crosby National CN22 flat bed tester, strapped a tire in, and tried to pull it out from under the strap.

The result? At 15,400 lbs, the test was stopped. The tire was still under the tie down, and as you can see in the photo, we compressed the tire a few inches. The strap got the higher work load limit, and we are confident the strap is suitable for the job. Did it really matter? Once again, yes.

We also get customer driven requests. A customer asked us to document the differences in the breaking strength of ratchet type load binders depending on how far in or out the hooks were relative to the ratchet mechanism. Test parameters were set up, and the testing began.

Load Binders at the Beginning of the Test

Load Binders at the Beginning of the Test

For the first round of testing, a 5/16”-3/8” load binder with a Work Load Limit of 6600 lbs and a Minimum Break Strength of 19,800 lbs was tested. Three samples were tested: one with the hooks wound all the way in, one with the hooks 1/3rd of the way out, and one with the hooks 2/3rd of the way out.

The samples were then hooked onto a section of 3/8” grade 80 chain. Each end of the chain had a clevis grab hook, and loops were formed over the hooks of the test bed.

Load Binder and Chain in a Test Bed

Load Binder and Chain in a Test Bed

Force was applied to the point of failure, the results were graphed and photographed. So what happened? Here are the results:

Hooks all the way in: one grab hook on load binder opened at 23,275 lb

Hooks 1/3rd of the way out: one grab hook on load binder opened at 23,711 lb

Hooks 2/3rd of the way out: one grab hook on load binder opened at 21,396 lb

So did it really make a difference? In this case, no. Regardless of the hooks position, the load binders exceeded their Minimum Break Strength, and nearly four times their work load (remember: NEVER exceed a products Work Load Limit!).

Just to confirm our results, another group of load binders was tested. These were 3/8” G100 binders, with a Work load limit of 8800 lbs, and a minimum break of 26,400 lbs. The test set up was the same, using 3/8” grade 80 chain. This time the results were a little different:

Hooks all the way in: chain broke at 29,889 lbs

Hooks 1/3rd of the way out: chain broke at 22,089, where binder was hooked

Hooks 2/3rd of the way out: chain broke at 22,029 where binder was hooked

GRAPH OF TEST. CHAIN FAILED AT 22,029 LBS

Graph of initial test

Graph of initial test

So what happened? First, the Work Load Limits were mismatched. Binder Work Load Limit is 8800 lbs, 3/8 Grade 8 chain WWL is 7100 lbs. One test went above the Minimum Break Strength of the chain (28,400 lbs); two were below the MBS. In both cases, one of the links the binder was hooked to failed. This is known in the chain industry as a Preferential Failure. Because of the way force is applied to the link by the grab hook; it can fail at up to 20% below the chains MBS. Chain is designed to be pulled in a straight line, not from the side. Also remember, that an assembly is rated by its weakest component, and once again, NEVER exceed the products Work Load Limit.

So did it really matter in this test? I’ll have to say yes and no. No because the position of the load binder hooks did not affect the result of the test. Yes because the differences of the Work Load Limit of the components did affect the test, as well as the Preferential Failure.

I’ve asked the question does it really matter several times, and answered some with yes and some with no. The answer to all of them should be yes. We test to make sure you get the best product available, every time. It matters because when we ship a product, any product, we want there to be no question it will do the job for which it was designed., every time. Yes, it really does matter.

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