Anchor Chain Corrosion

[Zoid]

I purchased my boat in November 2013 with brand new galvanized chain (it was a new boat). After my first year cruising I am going through and cleaning/inspecting everything and just noticed this on the anchor chain. I had seem some "white rust" which I don't believe is a big deal, but on part of the chain it appears to show some real rust. I'm a new sailor and don't know much about this, but is this an issue? Is this normal for a 1 year old chain?

Thanks for your help,
Zoid

[transmitterdan]

What brand chain is it?

[Zoid]

Originally Posted by transmitterdan

What brand chain is it?

Good question. I actually do not know. I will try and hunt that down and let you know. I know there are differences in chain manufacturers, but does it make a difference as to whether the reddish color I'm seeing is bad or not?

[transmitterdan]

Some letters should be stamped on each link. What are the letters?

[Zoid]

Originally Posted by transmitterdan

Some letters should be stamped on each link. What are the letters?

Would you believe me if I said there were no letters on the links? Checked thoroughly on multiple links.

[transmitterdan]

Then it is probably some off brand off-shore made chain. Thin galvanizing and resulting rust is not unusual in cases like that. Chain made in US and Europe is supposed to have manufacturer identifying marks on each link. The obvious reason is in case of failure safety officials know who made the chain.

As to whether the rust is a safety issue I cannot say. But it makes sense to me to only buy chain from a manufacturer not afraid to put their stamp on it.

You can try discussing with the store where you bought it. They may offer a warranty but I'm guessing not.

[rockDAWG]

No name means it comes from a no name small shop in China. If it is from a good shop in China, they will put their name on it.

Sorry.

[zeehag]

looks like you still have good chain. when there is so much rust you cannot see the metal, then worry. especially if there is loss of metal.
mic it.
chinese steel is ok, is the galvanising that sucks, as gaps have been found upon inspection.
regalvanizing is an option.
so is purchasing more of the same chain under a different name......
.

[Cheechako]

I've had G4 and BBB from American makers (bought the whole barrel) and there was no stamped numbers on the links. This info is close to 15 years old though. That brownish white surface.... are you sure it's rust? Is it next to t he anchor?, in the middle? etc Where do you cruise? Looks a lot like Chesapeake mud to me!

[AnchorageGuy]

From the picture, you still have many more years on the chain. Sand, mud and salt water coats the chain every time you use it. Don't worry about it until you start to see rust particles on the deck from retrieving the rode, and then replace. Chuck

[Alan Mighty]

Originally Posted by Zoid

I had seem some "white rust" which I don't believe is a big deal, but on part of the chain it appears to show some real rust. I'm a new sailor and don't know much about this, but is this an issue?

Anchor chain performs two or more functions, including 1. providing strength equal to that of its weakest link; 2. supplying weight forcing the anchor rode into a catenary shape that forms an asymptote as it approaches the anchor so vector of drag on the anchor is close to parallel to the seafloor surface; and 3. resisting abrasion against the seafloor. (Nos. 1 and 2 are relative to a rode formed from cordage).

Functions 1 and 2 derive from each link. And the key parameter is the diameter of the thinnest link.

Let's say that your boat has, like my Led Myne, chain links with nominal (or original) diameter of 7/16" (7.94 mm).

Unless you expect severe conditions, that chain will remain serviceable as long as the minimum diameter of the weakest (thinnest) link is 7.00 mm.

Abrasive wear and corrosion will largely be at the anchor end. You can reverse the chain to even out the wear. Or you can cut off abraded links and rusty links, thus shortening your rode.

If you see links that are cracked or exploding, then condemn the chain (or cut off a section of chain to remove that). If you see links thinner than the minimum diameter, then condemn the chain or cut off a section of chain.

The zinc galvanising coating will normally develop a white powdery state from being wetted with saltwater. Once the zinc galvanising is thinned by abrasion with the seafloor, surface or superficial rust is normal. You need to distinguish between superficial rust and deep rust.

So feel empowered to haul out your chain, wash it with fresh water, and inspect it, including using calipers to measure the diameter of links.

Al

[MVNightWatch]

No one has mentioned any coating or paint, grease, lube, etc., regarding preservation of anchor chain. Anyone know of anything in this area, especially a product that won't pollute the waters or my decks when I hoist! Teflon or PTFE acceptable? They might make the mud slide off....

[a64pilot]

Originally Posted by MVNightWatch

No one has mentioned any coating or paint, grease, lube, etc., regarding preservation of anchor chain. Anyone know of anything in this area, especially a product that won't pollute the waters or my decks when I hoist! Teflon or PTFE acceptable? They might make the mud slide off....

I think the "white rust" is zinc oxide, and the best and longest lasting coating is zinc (galvanizing)

I've read that Teflon is toxic, but as it's used inside of the human body and on cooking surfaces, that doesn't seem to make much sense?

[JPA Cate]

FWIW, over the years, we've found that re-galvanizing the chain that subsequent galvanize jobs last longer than the original galvo that came with the chain.

[Paul L]

End for end the chain every year or two and you will extend its useable life considerably. The end of the chain that is near the anchor wears the fastest.