Have you ever broken your chain?

[bobconnie]

We got 22 yrs on our BBB chain in our Colvin, started seeing small wear pattern on the links. I changed shackles almost every year, and cked the chain at that time. We replaced it and Im sure it's still being used today LOL Seems to me ruleing out electralysis, normal chain should last for a heck of a long time with even heavy use as we had anchoring around 20 times to 2 days at a mooring or dock !! It needs cking on at least every other time ya ck the shackles! just my 2 cents , only saw one broken chain in my time at sea, and that was on what I would rate as a wreck looking for a place to happen

[skipmac]

I have been doing an informal chain test to see if I could break a chain. Took a old piece of 3/8" anchor chain (unmarked so no idea what grade) and hooked it to my tractor. I have been using it for 10 years now pulling stumps, towing logs, snatching it and abusing it in every way I can think. I also used an old stainless shackle to connect to the tractor to see how that held up.

I have towed up to 3 1/2 foot diameter, 20' oak and hickory logs hundreds of feet. Dragged dozens of 2 1/2' diameter sweetgum trees a quarter mile. Jerked repeatedly on stumps that were so big the tractor couldn't budge them. Finally the weld on the 1/2" steel plate holding the chain to the tractor cracked but the chain is still fine. The SS shackle was elongated and so deformed I had to cut it off to get the plate off for rewelding but not a crack or blemish in the stainless.

Of course no load cell or any way to measure the force but I have to say, after all this I don't think I'm worried about the chain breaking on it's own. Corrosion and loss of metal is another issue but as long as the chain is more or less whole, properly made and properly sized for the boat I think the odds of breakage down in the slim to none range.

[Stu Jackson]

If someone's chain broke, do you think they'd admit to using a swivel?

[charliehows]

have cut a few seriously rusty links out and had a shackle which was 10mm worn down to about 3mm - I had to cut it to get it off, it was still very strong in spite of the extreme wear. Think i agree with earlier comments about overkill - not that theres anything wrong with overkill on anchor systems.

[klem]

I have broken many pieces of chain although very few related to boats. Trying to get stuck machinery out, we have broken a number of pieces of 3/8" G70 and a handful of 1/2" G70. Needless to say that you need to be really careful about how the energy is dissipated in these situations.

We twice had the mooring chain let go on our old 19' center console motorboat which was moored in a somewhat exposed location so we had a 25' 3 strand pendant to try to put some stretch in it. One time, the chain was fairly worn and the shock loading got it in a storm that was only probably 40 knots steady with 4-6' seas at the mooring, luckily the boat found a soft spot in the marsh. If I remember right, this was 3/8" BBB chain and I would guess that the link that broke was down to under 5/16". The other time the boat got free was when the swivel broke. I believe that it was a 7/16" swivel that was the peened type not a nut type and it broke that part off completely. It must have happened in a thunderstorm at night because the next morning the boat was not there and it was about a mile away. All this happened a long time ago so I might not be remembering it exactly correctly.

On larger boats, I have broken various components of ground tackle. We broke a 1" shackle one time on a 90'er using the anchor as an ebrake. I watched another smaller 75' boat doing the same thing break a shackle that was somewhere between 3/4" and 1". I also watched a 70'ish boat break some worn 5/8" chain in a strong gale but I don't know what grade it was and can't say exactly how worn it was.

There do seem to be very few people who have ever broken their chain so it is probably safe to say that if you size it so that the expected load at 60 knots is less than the working load limit, you should be fine.

One little note on the different ratings like ultimate tensile strength and working load limit. The working load limit is a little bit arbitrary and is based on a safety factor and fatigue. While very few boats are in situations where high cycle fatigue is an issue, you should never claim that your chain is as strong as the tensile strength. There is a load that if you start cycling the load above it, your chain will fatigue and become weaker. With steel, there is a load at which effectively no number of cycles will cause the steel to fail and it is generally good practice to operate below this level at all times. This level tends to be on the order of 1/3 the ultimate tensile strength so the working load limit that is published is a decent guide. If you want to learn more about this, you can look up metal fatigue or S-N curves.

[Astrid]

it's hard to imagine any decent chain breaking before something else on board gives first.

[s/v Jedi]

Originally Posted by bobconnie

We got 22 yrs on our BBB chain in our Colvin, started seeing small wear pattern on the links. I changed shackles almost every year, and cked the chain at that time. We replaced it and Im sure it's still being used today LOL Seems to me ruleing out electralysis, normal chain should last for a heck of a long time with even heavy use as we had anchoring around 20 times to 2 days at a mooring or dock !! It needs cking on at least every other time ya ck the shackles! just my 2 cents , only saw one broken chain in my time at sea, and that was on what I would rate as a wreck looking for a place to happen

No worries, electrolysis is immediately obvious as it is like pieces of steel are eaten away from the link, i.e. it is not the whole link that becomes thinner.

Many will see links getting thin and replace chain while it was just the galvanize that came off. You have to check where two links are linked (?) and metal-to-metal wear will occur.

[Kettlewell]

We twice had the mooring chain let go on our old 19' center console motorboat which was moored in a somewhat exposed location so we had a 25' 3 strand pendant to try to put some stretch own to under 5/16". The other time the boat got free was when the swivel broke. I believe that it was a 7/16" swivel that was the peened type not a nut type and it broke that part off completely. in it. One time, the chain was fairly worn and the shock loading got it in a storm that was only probably 40 knots steady with 4-6' seas at the mooring, luckily the boat found a soft spot in the marsh.

This is one among many reasons why I don't like to pick up rental moorings. My anchor gear gets a partial inspection every time I use it, but who knows what lurks below the surface on a rental mooring? On one of my first cruises we were anchored in Lake Tashmoo when a gale came up and in the middle of the night, being unsure of our anchoring technique and equipment, decided we'd better pick up one of the many moorings in the area. After a long struggle in the dark and howling wind we finally reached the mooring, grabbed it with the boat hook, and the ball just popped out of the water and came disconnected from whatever was below and we blew off through the harbor. Went back to riding it out on our anchor after that. So, I suppose that counts as a firsthand chain breaking experience, though I have no idea what type of chain or how old.

[barnakiel]

We have never had, nor met with, a single case of anchor chain snapping.

We have seen quicklinks go and anchors bend.

b.

[Group9]

Originally Posted by Astrid

it's hard to imagine any decent chain breaking before something else on board gives first.

I grew up on a farm and we constantly used chain that we put under very hearvy loads and I can't ever remember breaking one. In fact, the one instance I do remember a breaking failure, was trying to pull up a stump with the 8000 lb pull power take off warn which we had on our truck.

I was trying to pull a large stump up and the truck kept sliding. I backed it up to a large oak, and chained the frame to the tree using standard logging chain (I don't remember the size).

When I put full power to the winch, it broke the half inch steel cable, that we used for years and never broke before or after that. The chain was fine.

[Thumbs Up]

Someone should offer a chain testing service. It would be great prior to regalvanizing, they could even offer a certificate.

[travisD]

Originally Posted by Thumbs Up

Someone should offer a chain testing service. It would be great prior to regalvanizing, they could even offer a certificate.

Most wire rope and chain supply companies offer testing services. They will also attach a stamped tag with the rated working load on it. Where I work all our slings, chains , and wire rope slings have to be tested and have a metal tag attached.
The testing service isn't that expensive and I am sure that most of these companies will have chain for sale at a much cheaper price than where most buy it.

[Kettlewell]

Someone should offer a chain testing service. It would be great prior to regalvanizing, they could even offer a certificate.

It doesn't seem to be necessary from what I am reading in this thread. If you purchase quality chain from a reputable company and then inspect it visually for signs of corrosion and wear you're good to go.

[s/v Jedi]

I special ordered our ACCO chain with these specs:

- 3/8" G7 chain
- enlarged end-links on each end
- hot dip galvanized

for which they charged me just over $100.- extra in 2005. When it came it had documentation that said that each link had been x-ray'd and was within spec and that each end-link was welded on before hot dip galvanize and was separately x-ray'd to confirm the weld.

I assume they x-ray each link anyway in an automated process, but I was surprised how much extra work they did for just $100.-

cheers,
Nick.

[cfarrar]

Nick, if ordering enlarged end links, would it be practical to specify 2 or 3 large links at each end, so you could cut off an end link if it became especially corroded or worn? Or do you think that's silly and unnecessary? Or maybe it wouldn't fit the roller assembly?