Tested vs Chinese chain

[goboatingnow]

For metric chain , Its simple din766. Usually grade 40


Dave

[onestepcsy37]

Originally Posted by Cheechako

I would think some sort of testing program would be good. OTOH, it doesnt mean squat on it's own if the manufacturing process isnt controlled to the point of statistically eliminating out-of-spec chain. In other words, testing a few links doesnt mean there wont be one link ready to fail out of every 100 links!
Now if you buy from a supplier who is ISO certified, they are already testing the chain to statistically eliminate bad areas. (in theory anyway) At least they are watching things a little closer.
Chain is made by machines, machines wear, welding componants go out of spec. If they have problems while your drum of chain is being made, you will have weak links.
The only thing that will solve this is a controlled mfg environment.
Doesnt make you feel warm and fuzzy does it.....?

On the strength of one link in the cable,
Dependeth the might of the chain.
Who knows when thou mayest be tested?
So live that thou bearest the strain.

- Rules of the Royal Navy, 1755

[JonJo]

Originally Posted by Cheechako

This is pretty interesting from that site: "..Every sample achieved the required strength for its grade but it was noticeable that every Chinese Grade 30 chain, with one exception, delivered the strength of a Grade 40. The result suggests that steels used for Grade 40, typical of constructional steels, are more readily obtainable in China than the lower carbon steel used for Grade 30."

If this is an independent finding it is valuable but it has a striking resemblance to a finding by YM of chains they tested about 12 months ago but I vaguely recall sampled 12-18 months prior the tests. Try Vyv Cox website (coxengineering?) Tests conducted in NZ might contradict these findings - try Chains, Ropes and Anchors. I'm not that motivated to consider Chinese so results are not that important to me (I might be tempted come the time), I prefer locally made, here PWB, Serafini; Europe Maggi; US, Campbell, Peerless and Proof Tested. I think maybe there are few other European chain makers still making. But I am sure CMP chain ought be good, pending results showing otherwise.

There are 2 interpretations - 1, the Chinese are over engineering or 2, the Chinese are using whatever is in excess supply.

Jonathan