Skid Lifting Impact Factor

[ibrov]

What is reasonable impact factor for skid (about 50-60 ton weight) during lifting using Allowable Stress Design ASD. Is 25% to low?

Any reference would be greatly appreciated.

Best Regards,

Ibro V.

 

[JWB46]

25 % as an impact factor is probably ok but you also need to allow for unequal load sharing in the slings. 75:25 split is commonly used (ie one pair of diagonally opposite slings designed to take 75% of the total load. API RP2A (for offshore lifts)requires a total factor of 2, which includes dynamic effects and unequal sling loads.
Hope this helps!