Securement (chains specifically)

I'd rather replace 2 twelve foot sections of chain then having the coroner tell my wife that it's gonna be a closed casket because the machine tore off the cab. Like it was said earlier. Grade 100 is a lifting chain.

 

I said fair enough, you have your opinion based on your experience I have mine. Leave it at that.

 

14 Years I've used them and haven't broken one yet, I have broken a couple of grade 7 3/8 and a couple of D-rings and I've been in a few bad situations.

 

Why wouldn't you want a lifting (grade 100) chain to stretch the same way a grade 70 chain stretches?

 

Because it's more brittle, it has more shear strength but less tensile strength. But it also has a much higher ultimate breaking strength.

 

You actually want it to stretch a little bit more. That's why G100 has to stretch 20% vs 15% for G70.

It's the chains way of saying "stop it, you're being stupid." If you ever get to see a chain undergoing destructive testing, when the chain reaches the end of it's elastic range it starts to stretch a bit and undergoes strain hardening, requiring even more force to be applied, as you keep pulling it reaches it's ultimate strength and enters the necking phase. The chain starts to get thinner and longer, it can't take as much stress and finally breaks.

If you buy a large amount of chain you can get the test sample from that lot of chain, the broken link will show the stretching, and necking that occurred before it broke.

Unless you use G43, any chain you use is going to be hardened. G70 and G100 are both hardened chain. The hardening process does make the chain more brittle, but the next step in the heat treat process is tempering. When you harden the steel you get it red hot, about 1600 F and then dunk it in water, that's called quenching, this makes steel as hard, but brittle. If you heat the steel up again to a lower temp, generally below 500 F and cool it off it reduces the hardness a but increases ductility and reduces brittleness.

The end result is a much stronger chain than you started with. It might not be as strong as it ultimately could be, but it has the best balance of characteristics.

Issues with G100 generally date back to it's early days (the 90's) or offshore manufacturers. Because it's an alloy (it has nickel and chromium or molybdenum added to it) the heat treat process is more difficult. The temps, and how long you hold them, how quickly you cool it all have an effect on the end product, and some of the early stuff was not necessarily done correctly.

 

The thing about this load is that I committed to it a week in advance. It picked up in Minot, ND headed for OKC, and I was in OKC. I used load boards to make money and position myself for this load.

Why did I do that? Because the load payed over $4K for the run to OKC. I don't mind having spent 4 hours securing the load. At almost $4 per mile I will do what it takes to make the load happen. That turned out to be an $8K week for me.

 

Yeah it may take a little longer then some folks to throw a strap but that load ain't going anywhere.