Joining anchor chain

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Kurrawong_Kid

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Having seen disturbing test results on the chain links sold in British swindleries, I wonder if anyone can suggest the best way of joining 2 pieces of 30 mtr length chain so that it can still go round the electric winch gypsy but can also hold about the same weight as the chain itself. The only thing I can think of is to have a shackle to put through the links of the chain after the join has gone past the gypsy on the way out and remove it before chain goes round the gypsy when recovering. Seems a bit impractical though.
 
Get someone who knows what they are doing to weld them togeather.

Or find a 'Crosby' made chain joining link. They are available in the UK and are good.
 
I have used a joining link, but had
it welded. But I only do coastal sailing, am a great believer in SEA ROOM and would not lay at anchor in anything more than a force six. I have 20 metres of 10mm chain, 40 metres of 14mm rope on a 4.5 ton boat.
 
Their online catalogue is not very user friendly and I couldn't find the items you mention.

West sell joining links that are stated to be of equal strength to their chain but unfortunately these are not made in short link, only long. However, my gypsy will take the occasional large link without problems, so maybe it's worth a try.
 
No you don't want a hammerlock, the things in the links above. Those are a Grade 80 fitting and could easily blow your winch apart.

Scout around for Crosby 'missing links'.

http://www.thecrosbygroup.com/productcatalog/maininterface.htm
then click on the 'chian and accesories' then the link picture which is 3rd row down and 5th from the left. Sorry one of those site where you can't get a direct link.

could not find any dealer list but this is the Crosby EU guy. Give him / her a tinkle and ask where to get them.
Name Mathieu Poesen
Phone 32-15-76-88-95
Cell Phone 32-475-23-60-87

No idea what country that is, somewhere in the EU I'm guessing.

These links are strong, safe and good quality.
 
I hadn't found this address before on the Crosby site, but it is definately there now!:

UNITED KINGDOM
Crosby Europe (UK) Ltd.
Unit 10
Fall Bank Industrial Estate
Dodworth / Barbsly
South Yorkshire S75 3LS
Sales Office: 44-1-226-29-05-16
FAX: 44-1-226-24-01-18
E-Mail: sales@crosbyeurope.co.uk
 
What is wrong with a connecting link like this one . I have used one to connect my chain. In fact mine is a galvanised steel rather than stainless. I did a bit of research on this, and found that these links are designed to be stronger than the chain of the same size, the s/s being the stronger. I decided not to use s/s as I didnt like s/s to galvanised interaction, tho I am not sure, having seen them in use in permanent mooring situations.
 
You may have seen the article I wrote in YM, in which we destructively tested a wide range of shackles, links, chain, etc. The UTS of 8 mm chain was around 4.5 tonnes. The intention of the article was to test equipment available in UK chandlers, so no mail order components were looked at. We tested two links of the type you show, although I will accept that the ones we looked at were possibly not of the same quality as yours. They failed at between 1.75 and 1.95 tonnes.

The problem is that the real breaking strength is totally unknown. I have also bought several from USA that claim to be of the same strength as the chain but I have some difficulty in believing these claims. The design of the links, even in a forged high-tensile steel, is inevitably weaker than a welded, closed link of chain. In the case you quote the products are stated to be cast. I find it difficult to reconcile the quoted strength with this manufacturing method. The forged SO660 mentioned on your page looks to be a better buy but I cannot find it on the site.
 
Don't think I would want to put a stainless link on my galvanised chain either. Hadn't seen this source before - do you know what the SWL or WLL of your galvanised one is?

I have just cut off a Plastimo C-link that has been on for a season, but looks pretty rusty.

I would be interested in a metallurgist's view on this. The two halves of the C link had completely fused together and the join was not visible, although the two gaps where the C links meet had not filled themselves in (they had on my last C link which I hapily used for 10 years), and thus was presumably relatively weak at this point.

Is it that a good C link, once fused, is a lot stronger than one that is fresh on, and still in two pieces? The YM test was very interesting, although presumably they used a C link that had not fused together.
 
I can't find an off-the-shelf sailboat that has a horizontal windage at anchor in an F12 that would require a chain with a greater UTS than 1.32 tonnes.

Perhaps you could expand on why ultra UTS's are or may be required. Or are you just plain scaremongering?
 
As has already been posted. Definitely not scaremongering and as I said in the article. Snatch loads are far greater than wind-generated horizontal loads: the precise value is difficult to estimate but a real impact load, with the chain alternating between slack and pulling up bar tight, might generate a factor anything between 2 and 10 times the steady pull load. Even the yawing loads, calculated in the Alain Fraysse website, gives values much higher than those you mention. I believe the ABYSA figures are also a lot higher, although I don't have them to hand.

If you refer to the many anchoring threads on these forums you will find several reports of chain fracture during adverse weather. I had a swivel fracture, although this was due to stress corrosion rather than tensile overload, so probably does not count. The fact is, though, that it fractured and could have landed us in deep trouble.

My preference is to eliminate the weakest link as far as is practicable and the joining link is one that stands out as being less than half the strength of everything in the anchor/shackle/swivel/chain/cleat lineup. Always allowing, of course, that the holding of the anchor is probably the most unreliable factor of all.
 
I am walking on egg-shells as I write this, but I am not always impressed with YM tests. Statistically, the sample size is too small to be realistic and often, perhaps not in yours, they tend to be biassed by predisposed opinion. A further point that worries me is that when I went buying chain in UK chandleries (east and south coast) I found they either did not know where the chain (and, presumably accessories like chain links) came from, or admitted it was the cheapest they could find. This was their <u>selling point!</u> , ie "you won't find chain as good as this anywhere cheaper". I ended up buying it from a chain-only supplier on the Isle of Grain, who also supplied the links. I cant remember the name of the manufacturer, but it was Scottish and so were the links. Apart from Gordy Frown, I trust the Scots (except those who post here!). /forums/images/graemlins/tongue.gif

PS. One aspect of your tests was OK, you were using 'proper' equipment. I hate reviews that are based on kitchen science.
 
I agree: the sample size was very small but we achieved what I consider to be pretty logical agreement between nearly all the tests. It took us a very long day to test the ones we did and duplication would have been almost impossible. The unreliable results were from the low-cost galvanised shackles, for which the SWL was so low that they achieved it anyway. On the yachting kit, stainless and galvanised shackles and swivels, the results more or less followed what one would have expected

I may well be wrong but I suspect that very little chain is being made in Europe. China seems to produce virtually all of it, although I don't subscribe to the generally held view that it is therefore poorly made. All calibrated chain intended for boating use is to DIN 766A and ours certainly exceeded its nominal UTS by a good margin.

I have known the Dennison test machine that we used for 30 years! When we had no further use for it we gave it to what is now Atlantic Engineering and they have used it ever since. A fine piece of British kit. Instron units that would now be used to generate nearly the same load are about a fifth of the size.
 
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