SWL query on this strap

[bobtailrangie]

Hiya

Got a 3m 3.5" wide strap

On the label it says swl 3000kg

Im wondering if this is ok for winch use with my 8000lb inch as it would effectively be doubled up?

Am i right in thinking the swl is rated on the strap in a single straight line?

Cheers

James

[BogMonster]

SWL for lifting and SWL for towing are two different things - different safety factor. I think your assumption is safe but it depends on the origins of the strap and what it was designed for. A lot of stuff looks under-rated on paper - winch hooks often have 1 ton or 2 tons stamped on them, but this is based on a large safety factor for lifting.

[zim]

At work we use lifting wire slings which are about 12mm in diameter that are rated for 3 tonnes - look at any winch rated about 12,000lb and they have this size cable a 5 tonne sling to me is a hell of a lot thicker than what they put on strong winches.

The strap in your original post will be fine

G

[FridgeFreezer]

An indication of safety factor - an H14 (14,000lb) winch is rated to safely lift about 1.5 tonnes, mine came from a utilities vehicle and has the safety stamps on it.

[MrKev]

Out of interest, and possibly a little pedantic: Do you know the age of the strap? As far as I recall, the term SWL (safe working load) was depreciated in favour of the term WLL (working load limit) for labelling 'general purpose textile straps'. WLL implies calculation be applied to determine the correct Safe Working Load under the conditions of use...

[BogMonster]

An indication of safety factor - an H14 (14,000lb) winch is rated to safely lift about 1.5 tonnes, mine came from a utilities vehicle and has the safety stamps on it.

The utility H14 is one of the very few that are rated for lifting though, 99% of winches on the market specifically say they should not be used for lifting.

[bobtailrangie]

Hi all, thanks for the replies + comments

Ive had another look at the label + it says 'WLL 3000kg'

It manufacture date is 10 2006

The bit im not sure what means is M=2.0 etc in the different ways of using it

There are no frays, tears etc + looks to be in good condition

Cheers

James

[FridgeFreezer]

The utility H14 is one of the very few that are rated for lifting though, 99% of winches on the market specifically say they should not be used for lifting.

Comparing the construction of the H14 and most other winches, I wouldn't be suprised if there was good reason for that I doubt most of them would have the safety factor to lift much more than a bag of spuds.

(Before an argument starts, I'm not belittling other winches, just pointing out the H14 is hewn from a cube of ali and a little over-engineered )

[Gromit]

The bit im not sure what means is M=2.0 etc in the different ways of using it

M is the factor by which you multiply the SWL, depending on how you are using the strap.

So, if using it as a choke, the SWL is 0.8 * 3000kg = 2400kg

if using it as a basket, the SWL is 2 * 3000kg = 6000kg.

(So, when winching, a basket around a tree is much stronger than a choke around a tree)

The M value for triangle configurations depends on the angle of the triangle corners (60/90/120)

[MrKev]

M is a WLL multiplier - i.e. if the sling is used in that particular configuration (i.e. doubled up with sides parallel) then it's safe working load is 2.0 times, i.e. 6000kg.

It should be made to BS EN 1492, and so the design will have been tested to not fail at 7.0 times it's WLL, but please bear in mind these figures are for static loads, and do not account for any snatching or other forces generated by the load moving.

Kev