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| This illustration shows the basic sling hitches. |
| It also shows capacities for a single sample sling, rigged with each hitch. |
| The sample sling's Working Load Limit in a vertical hitch is 500 lbs. |
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Vertical
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Choker
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Basket Hitches
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| Sample Sling WLL (lbs.): |
500
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375
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1,000
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866
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707
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500
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| This sling has a Working Load Limit of 500 lbs. in a vertical hitch. Used in a choker hitch, it would have a capacity of 375 lbs. Used in a basket hitch with the legs at a 90° angle to the load, it would have a working load limit of 1,000 lbs. Used in a basket hitch with the legs at a 60° angle to the load, it would have a working load limit of 866 lbs., etc. - Why? The angle at which a sling is used, and the number of legs lifting the load can significantly effect its capacity. The formula for this calculation is shown below. |
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| Vertical - When a sling is used in a vertical hitch, the full lifting capacity of the sling material can be utilized. |
Choker - Due to the stress created at the choke point, slings rigged with this hitch achieve only about 75% of their potential capacity.
Always pull a choker hitch tight before a lift is made - never during the lift. (more, click here) |
| Basket Hitch (90°) - The cradle configuration of this hitch allows the two extending ends (legs) of the sling to function as if they were two separate slings. The capacity of the sling in this hitch is twice that of the same sling in a vertical hitch, but only if the sling angle of each leg is 90° (see right). Lifting with both legs at 90° would normally require two lifting devices or a spreader bar. |
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Basket Hitch (less than 90°) - When slings or sling legs are used
at an angle during a lift , the sling capacity is reduced. How much it is reduced depends on the sling angle (see above and table, right). |
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| Note that the rated capacity of a 30° Basket is only one half that of a 90° Basket. Sling angles below 30° are strongly discouraged. A sling angle of 60° or more is preferred. |
Sling Specification Tables -
Sling tables throughout our site contain the Working Load Limits of slings rigged with these hitches at certain specified angles. |
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Formula for adjusting the Working Load Limit of a sling or sling leg used at an angle:
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Vertical Hitch Working Load Limit X Number of Legs* X Sling Angle Factor = WLL at specified angle.
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The Working Load Limit for the sample sling above, in a 60° basket hitch would be calculated as follows:
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500 lbs. (Vertical WLL) x 2 (num. of legs) x .866 (sling angle factor from table) = 866 lbs.
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*Chain Slings: When adjusting the working load limit of four-legged chain slings, the number of legs entered in the formula must be 3 not 4. This is due to the difficulty of rigging a quad leg chain sling so that all legs share the load equally.
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| Use the formula below and the Sling Angle Table to estimate the lift angle. |
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H / L = Sling Angle Factor
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| To calculate the reach for equal legs needed to rig at a 45° or 60° angle. |
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Reach at 60 degrees: L = 2 x D
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Reach at 45 degrees: L = 1.4 x D
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On Multi-Leg Slings:
Reach = L
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Slings in a Basket Hitch:
Reach = 2 L + the distance around the load ( from lift point to lift point.)
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