Snatch strap/rope info

[The WEHI]

okay so i was looking around the net as you do and stumbled on this information. these are all quotes from another site.



"Here are some previous comments regarding this subject by Micheal Green, of Securetech/Spanset, who's also a member of this forum.

There is some more and I'll post it when I find it

Quote:
good morning

no two recoveries are the same

each recovery is dependant on the following factors which will shorten or lengthen the kinetic recovery strap or ropes life span
(1)mass of the stuck vehicle
(2)mass of the tug vehicle
(3)speed of the tug vehicle
(4)how badly is the vehicle stuck
(5)stuck in mud is not the same as been stuck in sand
(6)how the kess / kerr is stored after recovery
(7)how many times in a 24 hour period the kess/kerr is used
(maintenance program
(9)distance travelled

a rope and strap is made out of the same material and therfore have the same or similar properties
(1)they will or must eventually wear out
(2)both require a recovery time period

how a kerr / kess works
(1)a kinetic recovery works because of the conversion of potential energy into kinetic energy
(2)imediate recovery ( the part that does the work)
(3)latent recovery ( the part that requires 12 to 24 hours to recover)
(4)these rules apply to both types of equipment

it can therefore be concluded that in principle there is no real difference between a strap and a rope and the rules for the strap applies to the rope and visa versa

difference between a kess and kerr
(1)kess is cheaper (kerr is about 2 or 3 times more expensive)
(2)kess has slightly less elongation 20% - 30% (kerr is about 30% - 40 %)
(3)kess packs into about 1/4 of the size of a kerr

in europe more ropes are used (as they have not had webbing available) while in australasia more kess are used (this is trend we follow here is south africa)

there is different elongation between a wet and dry strap/rope, there is also a different break strength between a wet and dry strap/rope

kess = kinetic energy snatch recovery strap
kerr = kinetic energy recovery rope

SECURETECH / SPANSET products available from Makro stores

hope this helps
M K G
Quote:
Good morning

Makro sell a 16 ton 10m Spanset / Secure-tech kinetic snatch strap and rope. No other independant dealer except Safari Centre in Cape Town believes that there is demand / requirement for such an article. If you have no success in locating one please reply and we will assist further in trying to locate one or deliver one to you.

As far as using two snatch straps in parallel we would NOT recommend such for the following reasons:
1- They would have to be the exact same length
2- As these items are made made/woven no two batches are exactly the same ellongation

A snatch strap/rope is worn out by the following:
1- Used more than once in 24 hours
2- Incorrect storage
3- Overloading
4- Incorrect material finishing
and many more
Quote:
#1~ Spanset/Secure-Tech have launched a NEW snatch rope with a minimum break strength of 8000kg and 16000kg / 9m and 10m supplied in a heavy duty Cordura type storage bag
#2~ Snatch strap/rope must be manufactured from high tenacity high elongation polyamide yarn. One cannot tell the difference between a snatch rope/strap and tow/pull rope/strap by feel or appearance. If the strap/rope is not labelled for application then treat it as a pull/tow rope/strap, because one will do major vehicle damage if you use a pull tow as a kinetic snatch recovery as polyester elongates by only 5-8 % at break.
#3~ A snatch rope/strap needs to be no shorter than 9m metres because one needs to be able to obtain a speed of between 15 - 30 km/h to energise the strap/rope.Snatch straps/ropes are available in any length up to 100m. With a 6m strap/rope you will not be able to create enough energy for the strap/rope to work effectively. Remember a snatch strap/rope works for one reason only - the towing vehicles kinetic energy is converted into potential energy of the stretched rope/strap. The energy is transfered by the rope to the bogged vehicle.
#4~ The individual who secures his strap/rope temporarilly or permently around his/her bull is looking for short to long term trouble. As straps/ropes are manufactured from textile they degrade over time with continuos exposure to weather and UV. Kinetic ropes/straps are especially susceptible to rotting as they absorb moisture and will rot if kept wet. Store in a cool dry place out of direct sunlight. "




Cheers

[The WEHI]

Basically say's that all snatch straps/rope, require a recovery time between uses to return to its prior length and ability, don't know how true it is but someone here might know.


Cheers jordan

[Twodiffs]

It's true...after a few uses if the stuck vehicle is still stuck then winch or use another rope/strop. After a few uses and due to the energy involved the strop or rope will build heat which can create weakness.

[LR90NZ]

Basically say's that all snatch straps/rope, require a recovery time between uses to return to its prior length and ability, don't know how true it is but someone here might know.

Cheers jordan

Yes, all very much correct and true and this knowledge has been around for years.
There's even been books written on the topic.
Snatch straps 'work harden' through over use and loses the ability to stretch and weakens due to heat. They only have a limited life and should be discarded if abused, but people don't seem to or want to understand.

[The WEHI]

seems like good info then. hope others that don't know get to read this. there will always be people that avoid using equipment safely though or properly for that matter. hope it helps others.