welding anchor chain

[Mr B]

Cheap chatty chain is easily distinguished as it is a different shape and size to certified chain,
It has bigger and longer links in it,
I use welded links with no problems,
All my welds are unconditionally Guaranteed 100 %, But thats my welding,
All my lifting chains are all certified and are tagged,
They are all put together with certified Hammerlocks,
Would I use a hammer lock in saltwater, No way Known, 6 months and the Hammer lock pin would have been eaten away totally with corrosion,
Even fresh water will eat out a hammer lock pin, They do need to be kept dry,
Being internal, You would never see the corrosion, Only way to check is to knock the pin out,
Hammer locks are not protected with heavy Galvanising, I think they are Zinc coated,
But that process is under 400 Celcius and wont effect the Tempering of the steel,
Hot Gal is 600 Celcius and will effect the Iempering temps,Which is around 450 Celcius,
It needs 950 Celcius approx to effect the hardness of the steel, Thats a Dull red, Which anneals the steel,
Heat treatment of one link in an anchor chain is not nessesary, It is not a lifting chain, So no Guarantee is required, It will rust like the rest of the chain,
My 5/16th anchor chain will lift my whole 4.5 ton boat completely out of the water with out snapping, If my cleats didnt rip out of the boat first, They wont hold 4.5 ton out of the water,
I personally have never heard of a decent anchor chain snapping,
You just dont use cheap chatty chain on a decent sized boat, , Unless its a tinny, But Tinnys are never out in rough water, And most use rope on their anchors,

FWIW, Modern Butt welders that weld chain is the same machine that welds Rail line together, Or steel beams,
It takes approx 115 seconds to Butt weld two pieces of 170 LB rail line together, Just for an example of the time it takes for the actual weld,,
1/4 inch chain, is all automatic, cut, bent, rolled and welded would possibly take ten seconds per link, Total,
2 inch thick links take about 15 seconds to weld, But about 15 minutes each to heat the link to 1100 Celcius, , bend it to shape and put it in the machine to Butt weld,


This is the weld prep to hand weld chain of any type,
Butt welded is two flat ends pushed together and jumped up when hot,1250 C approx, ,

[geoff3nebel]

Best to use a pair of load tested shackles. Ok, they won't pass thru the pawl of a windlass so you stop it hand haul the join thru it, but I wouldn't trust a weld OR the two part chain joining pieces that you hammer together. How much is your boat worth to you?

[Bill_Giles]

5/16 chain weighs 0.93lb per foot. You already have 93lb of chain and want to add a further 56lb. If your windlass fails could you haul up 150lb of chain plus the anchor? Anyway, I don’t believe that there is any way of being assured that the link would ever be as strong as the chain. If I were determined to have all that chain, I would sell the two shorter pieces and buy one long length.

[Carl-T705]

I'm sure a welder could weld your chain, A sign on a welding rig claims they can weld and repair anything but the crack of dawn or a broken heart. I'd bet if it should break he could repair it again. Welded link repairs are not trusted (or approved) in any venue of lifting nor securing anything in my years of dealing with chain for both types of jobs. Also saying welding is akin to saying gluing, there are a few different methods of welding, TIG, MIG, stick , gas. You would want to know the method. Also when a welder says he'll shoot some spray paint on it, that's comical. The spray paint will last about as long as it takes for the welder to cash the check.
If I was in a position to have to lay out 101- 160 ft of chain , I would find it painful to lie in my bunk worried about what could be the weakest link in my strongest chain.

[RaymondR]

Originally Posted by geoff3nebel

Best to use a pair of load tested shackles. Ok, they won't pass thru the pawl of a windlass so you stop it hand haul the join thru it, but I wouldn't trust a weld OR the two part chain joining pieces that you hammer together. How much is your boat worth to you?

The problem with this solution is that the load rating on the shackles which have pins which will fit through the links is probably much lower than that of the chain.

[Simi 60]

Originally Posted by RaymondR

The problem with this solution is that the load rating on the shackles which have pins which will fit through the links is probably much lower than that of the chain.

Having just gone through this exercise I call BS.

I could, if I chose to , have bought rated/tested shackles that are higher rated than the chain and the pin would have gone through the link.
You will have to buy them from "not a boat place"

[atoll]

Originally Posted by RaymondR

You do not cut the links in half, you cross cut the link through the semi circular end part. What I mean by cross cut is you cut through the end of the link at 45 degrees then, you cut it in the same place at 90 degrees to the previous cut. What you end up with is a whole link which will fit together with a similarly cut link on the second part of chain.

You then weld the four V shaped gaps in the links thereby achieving what is known as "a fully penetrated weld". No cutting links in half just X shaped cuts on the end links which allow the end links to be fitted together then the V shaped slots filled with weld. Doing it this way the welded portions are not placed under tensile loading they only experience shear loading.

When I finally figure out how to get images from my phone to the chromebook I use for email I will post some images.

there is another way,using only one link to join the chain,rather than 2 links.
this requires putting your end link in a vice and using a large adjustable spanner to open up the link,that has been cut on the join line.

with the lower side of the link held length wise in a vice twist one side from the cut in the center to the right,5mm and the other side to the left 5mm,insert the 10mm chain being joined, then twist the two sides back together so they meet exactly, prepare the weld by grinding out,then weld. use galvanizing spray to protect. works for me

[Tomaz473]

I have 50m of 10mm chain which started to rust, so I gave it re-galvanised.
All looked OK, the links did not stick, to my untrained eye all looked nice. After a while, I noticed one link developed rust at the weld.
The weld also looked different than other (original) welds on the chain.
That link was 25m from the end.
My conclusion: The galvanising shop must have cut my chain in half for easier handling (perhaps their chain galvanising drum is not big enough for the whole 50m 10mm chain), then they welded it back together and used zink paint over the weld.
They never informed me about it.
Now I do not trust my chain any more as I have no idea how strong that weld is and I feel bad about it, so I plan to replace that with a C link.
I already have a C link to connect my 50m chain to additional 25m of a chain. Sometimes I do need more than 50m of rode and I used to have 50 m of chain and a rope after that. Whenever the rope was used it twisted a lot, so when I was retrieving the rode I got my chain all twisted on a gipsy. That was the main reason I upgraded the chain to 75m in total.
My strategy for really bad conditions is to use a spectra loop over the C link for additional protection. The loop just passes through the links and on paper is stronger than the chain. If the C link brakes then the spectra loop would take the load.
Do you think this makes sense?

[RaymondR]

Originally Posted by Simi 60

Having just gone through this exercise I call BS.

I could, if I chose to , have bought rated/tested shackles that are higher rated than the chain and the pin would have gone through the link.
You will have to buy them from "not a boat place"

Even if so try to find shackles which will pass through the anchor winch. Just fully penetration weld it and then you can forget it.

[Jim Cate]

I am amused by folks who will trust a weld with no certification or testing, but not trust a joining link that is certified by Crosby.

Both likely to be quite all right, but the logic disconnect is odd to me.

Jim

[RaymondR]

Originally Posted by Jim Cate

I am amused by folks who will trust a weld with no certification or testing, but not trust a joining link that is certified by Crosby.

Both likely to be quite all right, but the logic disconnect is odd to me.

Jim

There are field installable chain links I trust Jim (Hammerlocks for instance) but none of the ones I trust will pass around an anchor winch.

One becomes exposed to an enormous range of chains and fittings in the oilfields often working it to close to and beyond it's breaking strength.

[Simi 60]

Originally Posted by RaymondR

Even if so try to find shackles which will pass through the anchor winch. Just fully penetration weld it and then you can forget it.

I never implied they would pass through a chain wheel I was pointing out that your comment was incorrect and no,even though I am a trade qualified welder I would not be so flippant as to just "forget about" a welded link with our lives and 65 tonne riding on it.

[captwylie]

Originally Posted by RaymondR

I have been welding my anchor chain for about three decades now and never had a problem.

If you want the chain to pass through your anchor windlass and retain a reasonable percentage of it's original strength welding is the only viable joining technique, any of the chain connectors which retain the form of the original chain links will suffer from a far greater reduction in tensile strength than a welded link.

All the joining links which retain the full tensile strength of the chain tend to be significantly bulkier in form than the original chain links and will have problems passing through the windlass.

Galvanizing rods which allow re-galvanizing of weld heat damaged galvanizing with an oxy torch are available.

I agree with RaymondR. I have welded chains for 40 years with great success and the galvanizing rods work great.

[captwylie]

Originally Posted by captwylie

I agree with RaymondR. I have welded chains for 40 years with great success and the galvanizing rods work great.

You can get a welded chain tested at a reasonable price. We built some tools by welding a small piece of chain to a pair of hooks to be used for picking up heavy flanges to weld on the ends of large diameter pipe. We were not allowed to use this tool unless it had been certified for the weight of the flanges. I took the tools to a weight and scale company that certified scales. They attached the tools to a 8,000lb weight and raised it up and set it back down and certified the tools for 6,400lb, 80% of what they had lifted. I think they charged us $50 to certify the tool's weight capacity.

[RaymondR]

Originally Posted by Simi 60

I never implied they would pass through a chain wheel I was pointing out that your comment was incorrect and no,even though I am a trade qualified welder I would not be so flippant as to just "forget about" a welded link with our lives and 65 tonne riding on it.

If it shows, the attachment is for a Plastimo link of the type I think we are discussing. Firstly, note the warning on the right hand side.

Secondly, look at the construction and it is apparent that a number of the tensile loaded parts of the link have a cross sectional area of only 1/2 of the chain diameter, there are 4 of them, which 1/2 areas are all under tensile loading.

In contrast when using the method of joining and welding I propose none of the tensile loaded sections of the welded chain are under tensile loading, all the welded parts are only under shear loading.

Now, the shear strength of steel is generally lower than the tensile yield strength however, since we are using 70,000 psi yield rods and anchor chain is generally fabricated from steel with a lesser shear strength I believe it probable that the shear failure loading of the welds would be equal to the tensile strength of even the higher grades of chain even if the welds are not post welding heat treatment.

I'm going to rest my case on this one folks and if I can figure out how to get photos from my phone or camera onto this infernal machine will start another thread on welding anchor chain.