Chain recovery

[growler2058]

G'day all, I was taking part in the recovery of a tractor yesterday. We had the brother in laws duel rear wheeled John Deere as the recovery tractor. A Tractor stuck in a silage, joined by a drag chain.So both tractors were spinning all 10 wheels (both all wheel drives) so it was decided to put another tractor in front of the John Deere but nose to nose. I have a vid of the set up but not the result. Well I thought I read that a chain didn't recoil like a snatch strap or winch cable. Far out it does this thing snapped and as fast as the speed of light recoiled cracking into the stuck tractor. It stayed low and no one was in any obvious danger because they were up high but I will be using a damper if I ever use my drag chain for a recovery or to clear a track of fallen trees. Obviously two big tractors are gunna create a little more strain than the mighty td42 (haha) but if there was a weak link?!

[growler2058]

When I get home I'll chuck the vid up Can't do it from tappa crap I don't think

[NissanGQ4.2]

should of used that 4 wheeled honda, that would of pulled the tractor out no probs *L*

Just goes 2 show a damper should be used every time there is a recovery regardless what is used

[Silver]

My old man broke his 2 tonne working limit hercaloy drag chain a couple of times with his relatively little 4 wd tractor, pulling out stumps. I suppose some recoil could come from the attachment point as well.

How long was the chain growlers?

[Sir Roofy]

The amount of tension on that drag chain cant be compaird to pulling out a gq or any other 4x4
you would never have that amount of of power to start with,two tractors at 100 horse power each? That would pull your gq in half ,useing a damper still should be done regardless

[growler2058]

The chain was about 10m long. It broke only a coupla feet from one end so brother in laws happy it wasn't in the middle. I think it's just a good idea if you don't know what it's been used for in the past to use a damper there could be a damaged link. Mine I found on the side of the road so I'll be using a dampner if I try towing anything with it. I probably wouldn't bother with a smallish tree as roofy said even the ol td42 isn't gunna have the pull of two tractors

[Silver]

I think the length might have something to do with the recoil you saw - the chain would have a tiny amount of stretch - but added up over 9 metres would be enough to get the broken end moving.

We only play with a couple of metres of chain normally.

[Maxhead]

What sort of chains is everyone using? I've been looking at getting one but just haven't got around to it. I'm thinking a G70 8mm should do the job, about 8-10mtrs????????? or go something bigger???

[Silver]

I bought some 8mm chain from Serafinis in Brisbane - its a lot heavier than the 6mm stuff most of us use. 10m of 8mm would be a lot of weight.

Serafinis were great - the Senior Serafini took us for a walk around his factory - fascinating to see how the links were formed and welded etc. They were able to advise on the correct grade and gave us a great laminated card that showed how different ways of rigging the chain affected strength.

As to how much, the 8mm I had made up as a bridle for the old MQ - I wanted the snatch strap to be the weakest link, and the one I had at the time was 8000kg breaking strain - the 8mm was 8 tonne safe working load. Now I have gone down a completely different path - who needs a couple of metres of 8mm chain flying through the air if something fails? So I use a webbing bridle.

The other two lengths of 6mm alloy chain I have, are about 4m long.

I use them in places where I think a webbing strap will be subject to abrasion - so for dragging things over the ground. They also come in handy for setting up the hand winch sometimes. Although a webbing tree trunk protector goes around any trees in the process - unless it is the tree that is being winched out in suburbia :-)

My view is that 6mm alloy chain of the appropriate grade is enough, and I prefer chain grabbing hooks at each end, but plenty of people use hook at one end, loop at the other. How much? 4 metres. For longer spans I use the webbing winch extension strap.

The only place where I can see 10 metres of chain being an advantage over webbing, is where a snatch block is in use, and the cable and extension strap/chain are being dragged over the ground. the chain would cope better with that than webbing - and of course neither will go through the snatch block :-)

[growler2058]

Mines 8m of herc alloy so was the one we snapped yesterday

[Maxhead]

Just found this if someone likes the old stuff.

http://www.ebay.com.au/itm/ton-endless-chain-/110798938635?pt=AU_Car_Parts_Accessories&hash=item19cc21a20b#ht_500wt_1413

[iht2670]

8mm hercalloy grade 80 chain (2 ton SWL ) is the stuff for lifting & has a 4 to 1 safety factor that is 8ton of force to break it used with correct rated connecting hooks & links etc,
not hooked around tow balls or other items , weakest point will be where it is hooked back on its self.

steve.