Full Line Catalog Page 193 Safety Equipment And Supplies

193 slings SLINGS FACTS & FEATURES CONT. What capacity sling do I need? 1. Determine the weight that the sling will be lifting [LW]. 2. Calculate the Tension Factor [TF]. a. Using the angle from horizontal, read across the angle chart to the corresponding number of Tension Factor column -OR- b. Divide sling length* [L] by sling height* [H] (* Measured from a common horizontal plane to the hoisting hook) 3. Lifting Weight [LW] x the Tension Factor [TF] = Minimum Sling Rating for the type of hitch that will be used. EFFECT OF ANGLE CHART Reduction Factor (RF) Angle From Horizontal Tension Factor 1.000 90 1.000 0.996 85 1.004 0.985 80 1.015 0.996 75 1.035 0.940 70 1.064 0.906 65 1.104 0.866 60 1.155 0.819 55 1.221 0.766 50 1.305 0.707 45 1.414 0.643 40 1.555 0.574 35 1.742 0.500 30 2.000 Sling capacity decreases as the angle from horizontal decreases. Sling angles of less than 30 are not recommended. LIFT EVALUATION AND OPERATING PRACTICES IMPORTANT CONSIDERATIONS - Before buying or using a sling, know as much as possible about the lift you will make to minimize the potential dangers to personnel, product and property. All of the following items should be evaluated. Environment Crane and load foundation Obstruction in path of travel and for head height Power lines or other hazards Chemical conditions Temperature of load and surroundings Location of people - away from danger Inspect all equipment Load Weight of load Center of gravity (drain liquids) Pick-up point integrity, including location and number Edges that may damage sling Abrasive areas that may damage sling Secure or remove loose parts Structural integrity (bending and crushing) Rigging Type of sling required, including number of legs Type of hitch required Balance of load and stability, including flexing Prevention of load shift and movement against sling Angle of lift Tag line and spotter requirements Plan and procedures CHOKER HITCH ANGLES When lifting and turning a load using a choker hitch it is not uncommon to bend the body of the sling around the choker loop and have a severe bend occur around the body at this point. For choker angles of 120 or less, the choker rating must be reduced by multiplying the corresponding factor times the slings standard choker rating. EFFECT OF ANCHOR SHACKLE PIN OR CRANE HOOK ON SLING EYE Damage to slings can occur if the wrong size pin is used. The width of the pin or hook should never exceed the natural inside width of the eye. The eye dimension for each type and size of sling are shown in the capacity tables. If your pin or hook is large, request an oversized eye for the sling. Reduced Capacity Example: Vertical Choker rating of each sling = 6,000 lbs. Measured Length (L) = 6 ft. Measured Height (H) = 4 ft. Reduction Factor (RF) = 4 (H) / 6 (L) = .667 Reduced sling rating in this configuration = .667 (RF) x 6,000 lbs. = 4,000 lbs. of lifting capacity per sling L H L Increasing Tension Example: Load weight = 1,000 lbs. Rigging - 2 slings in vertical hitch Lifting Weight (LW) per sling = 500 lbs. Measured Length (L) = 10 ft. Measured Height (H) = 5 ft. Tension Factor (TF) = 10 (L) / 5 (H) = 2.0 Minimum Vertical Rated Capacity required for this lift = 500 (LW) x 2.0 (TF) = 1,000 lbs. per sling L LW = 500 lbs. 1,000 lbs. H LW = 500 lbs. WhiteCap.com 193 VISIT US ONLINE

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