Thickness of chain?

[vyv_cox]

Come on the metallurgists out there, is the extent of the corrosion due to the type of steel. Is it a higher carbon steel that will corrode more easily?

Except for very special circumstances, no chain that we are likely to use has a carbon content higher than 0.23%. Above this there is the possibility that brittle phases may be formed on welding. Grade 40 and 70 chains have a higher alloy content than Grade 30 and might be expected to corrode more slowly. Higher grades, 80 - 100, are used in hoisting applications but I have no information about their carbon content. The chain in the photos is long link, not a marine specification, and might be anything.

When I had a mooring my ground chain came from a lock gate on the Manchester Ship Canal and was thus a marine specification. Being short link it was far heavier than the stuff in the photos, and more appropriate to mooring ground chain.

 

[NickC]

To the chap I was talking to up on the Blackwater the other week who was asking about this: the boatyard that stiched us up with this secondhand chain is in Burnham on Crouch but it is NOT Priors.