T&T: All chain rode scope question

[bob england]

The question is simple, he needs a chart or table produced by a reputable 
source, for the use of an all chain rode. He wants to read from this source 
(galvy chain manufacturer ?) how much of what size chain for a given boat in 
a given situation. I must say "I have no idea" but have seen a D-9 
Caterpillar dozer pull a very large and heavy drilling rig workover unit 
(about 150000 lbs) uphill, in mud 5 feet deep, with 300 feet of 1/2 in hi 
tensile chain and it never straightened the chain anywhere near "bar tight" 
Lots of catenary. The next big blow that I attend will find me using a 3/8 
inch all chain road about 400 feet long with a kellet, and a huge by large 
anchor with a kedge, dragging sucks in a hurricane.