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Rave About Your Rack Please do not post retail SPAM.

Topic Date User

anchor testing rig 14-Oct-2010 At 11:41:15 PM GPage

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The following is a photo of my test rig depending on the exact use i have a few variations but this is where i tested the carabiners.

As you can see I have a needle thingy,also known as a pressure gauge,which is where the whole pressure surface becomes rellevant, as this and mikes rig read the force in pressure PSI which then needs to be converted into force.
#1- you need to know how many inch2 the PSI is working on.
#2- inch2 x psi ="X"lbf
( 1000lbf=4.482216 kn)
#3- "x" divided by 1000 x 4.482216= The force applied in kn

I have no reason to think the rig isn,t working properly , all components have been purchased new, and as i said crappy little faders biner with a rating of 12kn failed at 13, No disrespect to Mike but i'm sure that if my name was Mike Law you would have believed everything i posted!
And if you guys had been where i was standing today and saw the size of the test boulder which actually started shifting on me you wouldn't doubt the workings of my rig for a second! I had to stop doing tension testing for my own safety.
I don't understand what is so hard to understand about a biner breaking at double it's rating,it's called a safety factor, this allows for discrepencies in manufacturing and materials etc. My take on the rating is that it would be a max load which would still leave the piece in perfect working order, Not to far after the rating is where extreme deformation started to take place in my tests and once this type of deformation has occured the piece would be rendered useless.

Just shoot me an email Mike outlining what calculations you need.