is the maximum load applied to a rope to ensure longevity of that rope and is calculated by dividing the breaking strength of the rope by design factor
working load limits, points
Should not be exceeded
To ensure the longevity of
the rope,Always less than the
manufacture's catalog breaking strength
Determined by the employer
reduced working load limit
multiplied by the efficiency rating of knot or splice
catalog breaking strength
always more than the working
load limit,Average force in pounds
needed to break a rope
Reduces the longevity of the rope
Lifting loads that approach
the CBS of a rope can break the filaments of that rope
what is used for most rigging applications
slings
design factor
industry standard used to determine WWL
Design factors may range from 5 to 9
Companies will determine the
design factor
NLC design factor is 5
Efficiency rating of Eye Splice
95%
Efficiency rating of short splice
90%
Efficiency rating of Bowline
65%
Efficiency rating of Clove Hitch
60%
Efficiency rating of Square knot
60%
Efficiency rating of knots that choke
50%
Shock load occurs when
rope is pulled tight very quickly and with great force, the instant the slack is removed, shock load occurs
as sling angle decreases
sling tension increases
when calculating sling tension the weight distribution of load must be what
equal on all slings
what is used for most rigging applications
slings
sling angles can create what?
tensions that far exceed the weight being lifted
where is the weight rating stamped on parted block