Straps and Shackles

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OttoGSP

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Apologies if this has been asked before, I've searched but haven't seen a thread on it.

I'm relatively new to off-roading an am considering what sort of recovery kit I need but I'm slightly confused.

I don't have a winch so at the moment I'm looking at recovery straps and the associated kit that goes with them, shackles, dampers etc.

For my 2003 TD5 D90 I think I'll need an 8T strap and logic dictates that I'd want shackles or a similar or greater rating but the only guidance that I can find states that rated shackles should be used and that the shackle should be a 3.25t rating minimum.

Looking at recovery kits the shackles generally seem to have a lower rating than the straps. Am I missing something?
 
3.25t is a very precise limit. Think about the forces you will apply. You won't be lifting the vehicle but dynamic recoveries have a lot of force behind them. But more important than the shackles is what you attach them to. Recovery points will need to be good so you don't rip them off.
 
My Old Landy said:
I have the 3.25t rated shackles. They fit nicely in the jate rings on a Defender. I use both 7t and 10t straps (ensure they are for pulling not lifting as it is a different load. Only buy properly rated gear and not something that says it is.
These people are good https://slingsandstraps.co.uk/collections/tow-straps-10ton
They also do the correct shakles.
Click to expand...
They also come in handy when being strapped to the deck of a recovery vehicle iirc:D
 
A 3.25T shackle is typically the Safe Working Load. Depending on the quality that SWL is 3 to 5 times lower than the 'breaking load'. ie a 3.235T shackle will deform and break between 10 and 16 Ton.
3.25T shackles are also called a 5/8" shackle (the diameter of the body) or a 19mm shackle which is the diameter oif the pin.
There is a 9.5T shackle available (the nearest you can get to 10T) which is stamped WLL 9.5T but is actually a 54 (Fifty Four) Tonne (59.5Ton) shackle. The 9.5T weighs 3.66Kgs and has a 28mm diameter bow and a 32mm pin.

A (good quality, rated) 4 ton strap will nominaly break @ 20 tons with a straight lift, but less than 8 ton if it's looped around itself.
4 ton slings/straps fit nicely in a 3.25T shackle.
You can easily hang your landy up on this combination .... heavy thing straped to winch line, line through a pulley suspended by a 4T strap to a bridge, start the winch and landrover will be off the ground before you've finished your tea.

You want the strap/sling to break first .......

A Landrover weighs 2055Kgs
An 8mm diameter wire rope has a 4000Kg (4T) breaking strain. The wire will snap before the shackle breaks.
Dynema winch rope with a diameter of 9mm will break @ 7030Kgs and will also break before the shackle does.

The 4 High Tensile (12.9) 10mm bolts used to hold the front bumper/winch-tray to the chassis have a shear strength of 1.5 tons in 6mm plate section (actually they rip the steel plate @ 1.05T).
There are 4 bolts holding the winch plate/front bumper onto the chassis, the chassis (being a ‘box section’) will therefore distort/tear @ 8.4T (8 points @ 1.05T)
You really want the 'strap/sling' to snap before that happens...

SWL 3.25T shackle and WWL 2T strap/slings is a good combo.
 
Here I am pulling out a 110 with a 10T strap and 3.25t shackle on both ends of the strap.
Pulling out a 110.png
 
My Old Landy said:
<snip>
These people are good https://slingsandstraps.co.uk/collections/tow-straps-10ton
They also do the correct shakles.
Click to expand...

Their 'slings and straps' are rated to the 'breakstrain' ie their 7 ton strap will break at 7 ton. They are "tow straps" not lifting straps or cerytified WWL straps.
For example here https://www.safetyfirstlifting.com/2-tonne-duplex-flat-webbing-slings.html?gclid=CjwKCAjwzMeFBhBwEiwAzwS8zInmyDjrld_InNv1A5WfK1HdNwfsnqwU9gk2zqxmuD4v5HegJwzrjhoC1SIQAvD_BwE a 14 ton strap (classed as a 2 ton WWL) x 3M is £8.63 rather than £14.15
 
My Old Landy said:
You do realise that I already said that you need tow straps for recovery and not lifting straps?
Click to expand...

Well we'll agree to differ there then ;)
IMO you 'need' a strap that will (a) cope with the designed load and (b) not cost the earth. If a 2 ton 'lifting strap' with a 14 ton breaking load costs 1/2 the price of a 14 ton 'towing strap' with a 14 ton breaking load, then i'll buy 2 off lifting straps.
Actually i'll buy the 1 ton WWL straps as my poor old landys chassis won't cope with 14 ton but would likely not get damaged with 7 ton.
 
miktdish said:
Well we'll agree to differ there then ;)
IMO you 'need' a strap that will (a) cope with the designed load and (b) not cost the earth. If a 2 ton 'lifting strap' with a 14 ton breaking load costs 1/2 the price of a 14 ton 'towing strap' with a 14 ton breaking load, then i'll buy 2 off lifting straps.
Actually i'll buy the 1 ton WWL straps as my poor old landys chassis won't cope with 14 ton but would likely not get damaged with 7 ton.
Click to expand...
Fair play but I have been advised by the club that lifting straps will not take the shock loading. I tend to believe them and they make the rules when competing :)
 
My Old Landy said:
Well I haven't broken one yet ;)
Click to expand...

Thats because you not putting anywhere near the rated load of the strap.
Around 8.5/9 ton and you will pull the front bumper off the dogs. I've not worked out what the towbars pullout/shear strength is, it can't be a lot more although the chassis is plated and the rear X-member is thicker than the chassis but there are less bolts...
I think it's around 58.84KN (6 tonne) https://iopscience.iop.org/article/10.1088/1757-899X/713/1/012031/pdf
 
My Old Landy said:
Fair play but I have been advised by the club that lifting straps will not take the shock loading. I tend to believe them and they make the rules when competing :)
Click to expand...
I have lifting straps which have high ratings but wouldn't shock load them. I also have a "recovery strap" purposed designed for offloading from Procomp. You can get these from paddocks craddocks. I have used the recovery strap in multivehicle pulls that have broken 4t tow straps. I've also used it to pull a rigid water tanker, circa 18 tones with a jcb, 7.5 to 8 tons offroad. I would recommend the procomp to anyone, it has some elastic properties but I wouldn't let anyone recover me in a method that requires that, straight pulls only.
 
I have a procomp strap from paddocks anorl. 30 foot 9 ton. Also gorra 30 foot winch strap anorl. Can't remember the rating on that.

The main difference between recovery gear and lifting gear is lifting gear is always tested at full capacity. If it fails its scrapped in production Recovery gear they don't test all of them to full capacity as standard like they do lifting gear.
 
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