Question: We recently supplied slings to a customer for a project site and one of there main riggers refused to use the product due to the separation in the eye strands and some deformation and a couple of wire pops at crimp.  I was told that this happens occasionally as a result of certain wire specs/sizes and proof testing.  I reviewed the standards and didn’t really come up with anything concrete to justify the refusal to use the slings, or that these slings should definitely be accepted by an end user.
My own opinion would be that if the end user is not comfortable with the sling then we need to be sure not to supply these again but we also believe that they are perfectly safe especially since they were proof tested.

Answer: The sling is good and has not lost any capacity. The wire pushing out at the fitting is due to the wire sticking up when the sleeve was pulled on.  That sometimes can be fixed before pressing but not after.  Second the strand being pushed out at the crown of the eye is common when the flemished eye tails are too long and the sleeve pushes it out during pressing.  Neither of these affects sling capacity in a negative way since it is in the eye.  Any of this in the body is a problem.  Prior break testing of these “high strand” FE slings proves that they will still reach the minimum required breaking strength.  The body remains the weak point of the sling, not the eye where there is double the wire rope  Please go to the following website, under the video tab you will find a video discussing high stranding in the eye to prove the point on capacity.

http://www.iandisling.com/Did_You_Know/007/DYK_007.htm

I hope this helps,

Mike

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