Recovery Slings & SWL

[TarkMalbot]

I have been looking at building a recovery kit recently (see other thread) and have been looking at and thinking about slings and safe working loads.

When using a sling the safe working load (SWL) of a rated sling changes depending on how you use it so I was wondering if others took this into concideration when buying and using slings or they just bought one with a safe enough SWL to cope under any slinging method.

For instance I am looking at making a bridle out of a looped sling passing through the two front recovery points and by using this method, providing the angle from the recovery point back to the shackle point is less than 45 degree angle the SWL of the sling is increased by 40%.

If the sling is a straight line from one recovery point to another with a shackle at either end it would be the standard rating of that sling but pass the sling through one recovery point and have both ends shackled at the same recovery point the SWL of that sling is doubled. Plus using one less shackle takes another factor out of it.

Just wanted to know what other people thought about these methods. Not forgetting the 6:1 safety factor on rated lifting slings meaning a 1 ton sling could in fact be used to lift 6 ton with no problem. And its not very often you are likely to be hanging your vehicle off the sling but more than likely pulling it out of mud, over a rock up up a slope etc etc.

[scut44]

'Vehicle recovery equipment' is designed & tested as such,
plenty choice of vendors of the correct thing that can be trusted
& have the experience of what they supply.
Thats shackles, slings,ropes,bridles etc.

There is no saving in money by buying 'Lifting equipment' in my experience,
& its a false economy buying on price rather than quality IMHO.

george

PS i would not recover a 4x4 using one recovery point without using a Bridle if possible.
Do it on the likes of a Freelander with a pull at even a slight angle & it can be a wrecked front or rear.

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[Winnet]

[TheClunk]

I get lifting slings for nothing. The company dad works for sends parts over from their head office with slings attached for lifting out of the crates. He brings the slings to me as I use them for recovery and wrapping around things for an anchor when abseiling. They mostly have SWL's of 5,000 kg's. Although I do have a couple at 2,000kg's. The items they send over are usually less than 1,500kg so it's unlikely they have been used over limit.

[TarkMalbot]

I have a rigging and lifting qualification so am happy enough with the choices and uses of different equipment.

I started this thread more to see if others understood the way slings could be used to increase the normal working capacity and if they took that into concideration when setting up a recovery.

One thing I forgot to mention is how methods like a "choke" will decrease the rating of a sling by 20% so you really need a little understanding or you could be overloading the safe working load of the equipment without realising it.

[scut44]

Since you will know your equipment & will have trained or studied in the use & practice of rigging it, & understand about safety & working safely across paths/tracks etc.

First thing to check when setting up a recovery to someone elses vehicle is,

'its' recovery points & are they upto it. (then you fix your equipment on, dont leave it to them & their shackles etc)
Doesnt matter the strength/rating/capacity of your equipment or your vehicle.

More often if something is going to break or fail its the other vehicles recovery point that are not up to the job.
2 1/2 tonne LR's with rotted dumb irons, winch bumper with recovery points welded/bolted to rust, JATE's on rotten rear chassis & 110's with joey'd up rear cross members with a NATO hook on them.


Next thing is usually check out the driver of the other vehicle.
it doesnt matter how often someone says they know what they are doing,
(you done this before, are you OK with it? "yes of coarse i have!!!")

often they turn the steering the wrong way, thats if they dont have the steering lock still on, hand brake or foot brake on etc.

Have fun with it,
ever recovery becomes a further lesson in human behaviour.

george

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