Chromox Duplex (Stainless) chain for rode.

[GRIT]

Hurray, another anchor thread! Ok, anchor "chain" thread. But it's still a contentious topic.

I'd like to hear from folks using Stainless Duplex chain for anchor rode.

Our galvanized chain is not yet a year old, and we are not happy with it, so we're considering purchasing Chromox chain to use as our anchor rode.

I know all about what the internet says about using Stainless under the water, but I'm interested in hearing about Duplex chain (Chromox), which is rated at G60.

Unless you're a metallurgist, please don't contaminate the thread with internet "gossip" about stainless chain. I would prefer to hear from folks with actual experience using stainless (preferrably Duplex) chain for anchoring.

We'll be using 10mm chain, Din766.

Thanks all.
Paul.

[GordMay]

“Cromox” is a brand of stainless steel lifting products, made by Ketten Wälder, in Germany, manufactured mainly from 316L & 318LN steel.

➥ https://usstainless.com/chain/stainl...ain-8mm-by-10/

[GRIT]

Thanks Gord.

I'm under the understanding that 318ln is suitable for use submerged in waters up to 35C. 318 is a duplex steel, and is actually magnetic. Ultramarine seems to use it for the shanks of their anchors.

They talk about it a bit here: http://www.sailingfairisle.com/anchoring.html at the 17 minute mark.

They sell it here:
https://jimmygreen.com/1000-Cromox-G...ss-Steel-Chain as anchor chain.

And you can read a bit about it here: https://www.cromoxus.com/products on their website.

"cromox anchor chains exceed by far the requirements of DIN and ISO standards as far as their load-bearing capacity and exact running over anchor windlass wheels is concerned."

I'd love to hear from someone with experience with this chain, or similar chain.

If anyone's got experience with this chain, but does not want to subject themselves to the opinions on this thread, please send me a PM.

Cheers.
Paul.

[nfbr]

The 61ft cat I recently bought has 27yo 316 10mm and test samples pass pull tests fine.

I'm replacing due to paranoia, but likely it has plenty of life.

Reality seems to be, when exposed to air, crevice corrosion is limited.

Cracking - that's a question with all high strength steels. I think it's overstated.

The strength of 318L looks great

[CalmSeasQuest]

FWIW, I chose an Ultra anchor and swivel with CROMOX (316L) SS chain ground tackle for my Saba. I've only had it in service for 2 1/2 years but thus far it has functioned perfectly and shows no visible sign of pitting.

• 45 KG (99 lbs.) ULTRA 316L Stainless Steel Anchor
• UFS13-60 ULTRA Flip Swivel for 13mm or 1/2" chain with Bridge
• Loop
• SCG12 CROMOX Stainless Steel Chain, Grade 60, 12mm,
• 316L, DIN766, 31,300 lbs. BL, Electropolished (100 Meters)

[Muaddib1116]

I'm not a metallurgist, but the boat I bought last summer has Ketten Walder 10mm Duplex (318LN) chain, so I've done a fair amount of research on it. As GordMay pointed out, Ketten Walder does sell 316L Grade 60 chain under their Cromox brand, and I'm guessing it's probably the nicest 316L chain out there. Just make sure when you are looking at prices that you know what they are selling, the Cromox name gets put on any anchor chain from Ketten Walder.

Also, as you seem to know, the corrosion resistance in warm water of 318LN is much higher than 316L. This is expressed in the PREn, higher is more corrosion resistant. Duplex 318LN 2205 from Ketten Walder has a PREn around 35. I believe 316L is somewhere around 23/24.

They also sell a SuperDuplex 8mm chain that is also Grade 60. It doesn't seem to be stronger than Duplex, but I believe it has a PREn in the mid 40's.

There is definitely a conversation to be had about the pros and cons of galvanized steel vs duplex chain, and I can see both points, but the big thing argument against Duplex chain seems to center on cost. I think if it was the same price as G40 galvanized chain, the conversations about it would be very different and you would see a lot more of it out there.

[pjShap]

I've had Cromox CXI-10 Duplex chain for about 2 years now. I bought the chain because with the limited chain fall height into my anchor locker, the previous galvanized chain was castling and jamming every 6 feet or so of chain retrieval. With the Cromox chain I can retrieve 75 feet without a jam, making a huge difference for single-handing. I have not done any kind of testing, but chain has been problem-free.

[gabilo]

We have 80meter of chromox 10mm chain since 2014... still Perfect with plenty of anchoring

[nextis12]

Originally Posted by pjShap

I've had Cromox CXI-10 Duplex chain for about 2 years now. I bought the chain because with the limited chain fall height into my anchor locker, the previous galvanized chain was castling and jamming every 6 feet or so of chain retrieval. With the Cromox chain I can retrieve 75 feet without a jam, making a huge difference for single-handing. I have not done any kind of testing, but chain has been problem-free.

I have been looking for a solution to my anchor chain castling and jamming. Reading the link Gord provide and based on your experience SS chain would solve the problem and would be stronger. The site also mentions weight savings, has any one done the calculation?

The only hurdle appears to be price $4,500 for 300 feet of chain [emoji21]

[Muaddib1116]

I think the weight savings is implying that you can go to a smaller chain size because of the higher strength. I don't think the duplex steel is itself significantly lighter than galvanized steel.

[GRIT]

Thanks for your responses. I'm glad everyone is happy with their choices, I think we're going to go that route too.

I've just gotten pricing for CXI 10mm at $25.90 a foot, plus $3.77 for the electropolishing, which adds a year to the warranty, and is claimed to "seal" the steel.

Nextis12, I'm not sure what size you're getting, or if it's 316l, but $15 a foot is a little less jarring than $29.67 a foot!

I'm looking for 80m (about 265 feet).

Muad, thanks for the tip on superduplex, I'll look into that too.

Cheers.
Paul.

[Simi 60]

Interesting to see they claim 13mm grade 60+ is good for 167kn or 17000kg breaking load
Our 13mm galv grade L is 8100kg breaking load.

Reason why that is important to us is we have deformed Galv grade L twice now in 4.5 years so would not be putting on silly priced S/S if it was going to do the same but seems it may be OK?


https://www.bridco.com.au/cromox-loa...omponents.html

I do have concerns about disimmilar metals.
No way would I get a S/S anchor and I have an issue with s/s shackles.

[Muaddib1116]

I think that as long as you keep an eye on your galvanized shackle and the last link that it's connected to, you'll probably be able to catch any dangerous corrosion. I don't see why it would have issues down the chain further.

[GRIT]

I was surprised at the breaking strength, and equally surprised that the SWL is 50% of breaking strength. I usually see 25% of breaking strength as SWL, except in the USA where it's often 33%.

Paul.

[Simi 60]

In oz, SWL on 13mm grade L is 1.7t so closer to 5:1 or 20%