Stainless Anchor Chain

[Wand]

Seems the common view is that stainless chain is ill-advised for anchor work, especially long-term, because it work-hardens and becomes brittle.

But has anybody observed that in the field?

Or for that matter, does anybody have a different view about stainless for anchoring?

[bangkaboat]

I've never heard anyone mention that on the forums, probably missed the discussion so I'll search it, now. But stainless is less ductile than galvanized mild steel.

[Sandero]

The odd thing about anchoring "failures" is how few of them are reported to be from chain parting.

It should be noted that the chain is available for inspection as the anchor is set and retrieved. The beginning of degradation in galvanized chain is seen is rush and wear from friction. I've noticed some wear on the links right aft of the anchor on my galvanized chain. I cut those links off. I attribute this to the friction from the shearing of the boat about the fixed anchor.

Steel certainly might degrade related to the chemical environment, become more brittle and less ductile and this is likely not obvious from visual inspection.

My hunch as to why there are so few chain failures reported is that there is a reasonable safety factor for chain and this would be directly related to the forces on the chain... size/weight of boat, wind and wave conditions.

What say you?

[savoir]

Originally Posted by At sea

Seems the common view is that stainless chain is ill-advised for anchor work, especially long-term, because it work-hardens and becomes brittle.

But has anybody observed that in the field?

Or for that matter, does anybody have a different view about stainless for anchoring?

And your authority is . . . . . ?

I say stainless is the best. It's just the $$$$$$ which puts people off. You do want one size larger than G4 but otherwise brilliant.

Come and get me.

[Wand]

Originally Posted by savoir

And your authority is . . . . . ?

Sorry, meant to include that info in OP. A major chandlery in Oz, Whitworths, includes a warning in its catalogue to the effect that stainless chain is suitable only for day anchoring, and not long term anchoring, "as it can work harden and become susceptible to cracking".

I hadn't heard that before and, since plenty of cruisers would indulge in long term anchoring, thought I'd ask the experts in the field.

[savoir]

If I could afford one I would get a stainless anchor too. The stainless CQRs cost about 2k for 45lb.

I do agree that if you wanted chain for a permanent mooring gal would last longer.

[skipmac]

Originally Posted by savoir

And your authority is . . . . . ?

I say stainless is the best. It's just the $$$$$$ which puts people off. You do want one size larger than G4 but otherwise brilliant.

Come and get me.

Well the fact that most common SS alloys work harden and are more brittle than common carbon steel is metallurgy 101. If you want authority read any basic text or research on the subject.

Now whether or not this characteristic of SS alloys is significant in anchor chain is another question altogether. The answer would depend on so many different variables that a plain, black and white answer would be difficult to produce. Results would depend on the specific SS alloy, frequency of use, conditions of use and other factors. If you anchor infrequently and usually in mild conditions with little swell then SS chain may serve you quite well, even in an occasional blow.

Another problem with SS chain is that it is impossible to detect a weak or brittle link by visual inspection. You could have a link on the brink of failure and no visible evidence. With carbon steel chain the wear and corrosion is obvious.

[thinwater]

Doesn't work as well. Costs more. Done.

Sounds embarrassing, to get caught choosing one for your boat.

[David M]

Have a look at the SWL of the same sized stainless versus hardened steel chain.

[Bash]

from the Acco catalogue, stainless 5/16" 316L (S1) Stainless Chain has a working limit of 2,400 lbs. compare that with galvanized 5/16" BBB chain, which has a working limit of 7,600 lbs.

You'll ending up paying four times as much for stainless chain, and won't even get half the holding power.

Not a great investment.

[colemj]

Originally Posted by Bash

from the Acco catalogue, stainless 5/16" 316L (S1) Stainless Chain has a working limit of 2,400 lbs. compare that with galvanized 5/16" BBB chain, which has a working limit of 7,600 lbs.

You'll ending up paying four times as much for stainless chain, and won't even get half the holding power.

Not a great investment.

You must have looked at the wrong line. I see a WLL of 1,900 lbs for 5/16" BBB in their catalog.

Also, Acco do not sell a stainless windlass chain.

Maggi lists their 8mm (5/16") SS chain at WLL 2,755 lbs (using a 4:1 safety margin) and their 8mm G3 galvanized at a WLL 2,200 lbs (4:1 safety margin).

You will pay almost 4x as much, but you won't be losing strength.

Mark

[Bash]

Acco certainly deals in stainless chain. Check here: Powered by Google Docs

I also stand by the workload of 5/16" BBB chain I published above. Check here to confirm:http://www.westmarine.com/1/3/acco-chain-anchor-chain

[Mark Johnson]

SS chain is not nearly as strong, size for size, as HT-G4 galvanized. A frequent application that I have seen it used in nonetheless, is on aluminum boats. The SS apparently gets along with the hull material better than galvanized chain does. Presumably one just goes up in size to match galvanized...
M.

[annk]

Well we have stainless steel 10mm anchor chain. Been on board for over 12 years now. I have followed all the arguments against it's use on this and other forums and to date remain unconvinced that ss is less reliable than galvanized. I have found NO reports of ANY failures of ss anchor chain.

The plus side is that in twelve years it shows little to no sign of wear, certainly no rusty stains as in galvanized chain. It flakes far better than galvanised in the locker and is generally easier to keep clean than galvanized.

Sure the cost is massive maybe that's the real objection!

[GordMay]

Originally Posted by Bash

from the Acco catalogue, stainless 5/16" 316L (S1) Stainless Chain has a working limit of 2,400 lbs. compare that with galvanized 5/16" BBB chain, which has a working limit of 7,600 lbs...

From the linked West catalogue page:

Proof Coil Anchor 5/16" Pc Chain, 1900lb. Swl, 7600lb. Breaking Strength

Proof Coil Anchor 5/8" Pc Chain, 6900lb. Swl, 27,600lb. Breaking Strength