Chains

I think I paid aroun $5 a foot for g7 Half inch. Give or take a little.

 

I fully believe you, but do you have material backing this up? Working as a trainer now, and in the classroom, I need the written material backing up what I say and like having it all on hand. That, and this just interests me.

 

Of course I do, look here;
http://www.fehr.com/img/product/description/NACM Welded Chain Specifications.pdf

Page 5 paragraph 5.3.4

Grade 80 and 100 are required to stretch 20%, plus the higher ultimate breaking strength pretty well demonstrates they feasibility of using this chain for securement.

 

The other reason for using the higher grade chain? Direct tie downs only get half rating. Higher WLL on the higher grade gives you more when cut in half. Dependent on the WLL of your binders & tie down points of course.

 

That is a very good point!

 

I have to drill the difference between indirect and direct tiedowns into new driver's heads, and I never made that connection.

6,600 lb WLL attachment point, 4,700 lb WLL chain (G70 5/16"), 5,400 lb WLL binder (5/16") = 2,350 lb tiedown.
6,600 lb WLL attachment point, 6,600 lb WLL chain (G70 3/8"), 6,600 lb WLL binder = 3,300 lb tiedown

 

And 4,000lb wll attachment point, 6600 wll chain, 6600 lb wll biner = 2,000 lb tiedown.

 

No you get the full rating of the attachment point, if a stake pocket is rated at 4000 pounds you get the whole 4000, hooking a 6600# binder and chain to it then to the load gives you 50% of the chain/binder but you still get 4000 for the pocket so you would be at 3300. There is no 50% reduction for attachment points.

 

What makes you think that?

Sorry, I'm busy right now so I was going to come back to this but I'm going to elaborate right now.

The WLL of a chain is tested and determined by a single length of chain, not a doubled up chain, which is basically what a direct securement is.

The concept of cutting the WLL in half for direct securement and giving only the full WLL for indirect instead of more is only a legal concept, not a physical, scientific one. It is also why things only have to get secured to half of an item's weight.

Thus, yes, you treat the chain and the tie down point the same when doing the math.

 

The 50% rule is only addressed in terms of direct and indirect tie downs not anchor points. If a stake pocket is rated at 5400# and a chain is rated at 6600 and used as a direct tie down you get credit for 3300 not 2700. I've never seen anything that addresses reducing tiedowns except that they are not required to be rated. I would like to hear from one person who has been popped for that.