Rigging

Regardless of which hitch is used, keep the angle between the sling and the horizontal as large as possible. DO NOT exceed the sling's "safe working load" found on a synthetic sling's label. For the typical 6x19 IPS single-part wire rope the SWL can be calculated by multiplying the rope diameter squared by 8 (D² x 8). Avoid using chain in rigging. Remove a hook from service if it has been twisted, if its shank or throat opening has stretched more than 5% or if its body has stretched more than 10%.

Single vertical hitch For objects that can be lifted from one point. Attach one eye of the sling to the hoisting hook and the other eye to a shackle attached to the load. The force exerted by the object on a single vertical hitch is equal to the object's weight.

Single basket hitch Pass a sling under or through the load and hang both eyes of the sling from the hook. If the legs of the hitch are vertical, the force exerted on each leg is one half of the object's weight. If the legs of the hitch are inclined, calculate the force exerted on each leg by dividing the sling's length by the vertical distance from the hook to the attachment point multiplied by the objects weight divided by two. L/H x W/2

Single choker hitch The load is held in a noose formed by passing one eye of a sling through the other. The force exerted by the load on each leg of the noose is calculated by dividing the length of the noose by the height of the noose (height of the choke point above the load) multiplied by the weight of the load. L_N/H_N x W.
DO NOT use this hitch to lift loose material.

Two-leg bridle hitch For long loads. For summetrical objects use two equal-length slings. The force exerted by the load on each sling is the same and can be calculated by dividing the sling's length by the vertical distance from the hook to the attachment point multiplied by the objects weight divided by two. L/H x W/2
For asymmetrical loads, use slings of different lengths, leveling the load with a turnbuckle, comealong, or chainfall. Calculating the force exerted requires locating the loads center of gravity.

Double choker hitch Made from two single choker hatches. Calculate the force exerted on each leg of the hitch by dividing the length of the noose by the height of the noose (height of the choke point above the load) multiplied by the length of the sling from the hook to the choke point divided by the height of the hook above the choke point multiplied by the weight. L_N/H_N x L/H x W.

Double basket hitch Uses two two single basket hitches to blaance the load. If the hitch legs are vertical, the force exerted on each leg is one-third the weight of the load. If the legs are inclined, calculate the force exerted on each leg by dividing the sling's length by the vertical distance from the hook to the attachment point multiplied by the objects weight divided by three. L/H x W/3

Three-leg bridle hitch Used to lift large bulky objects. Attach three slings at evenly spaced points. Calculate the force exerted on each sling by dividing the sling's length by the vertical distance from the hook to the attachment point multiplied by the objects weight divided by three. L/H x W/3
If the object is asymmetrical, be sure to position the sling that carries the greatest load in the center of the hoisting hook between the other two slings. The load on each sling is calculated by dividing the sling's length by the vertical distance from the hook to the attachment point multiplied by the objects weight divided by two. L/H x W/2

Four-leg bridle hitch Uses four slings. The force exerted on each sling by the load is calculated by dividing the sling's length by the vertical distance from the hook to the attachment point multiplied by the objects weight divided by three. L/H x W/3
The four slings can be hung from the hook two ways. 1) Position one diagonal pair of slings in the center of the hook, sandwiched between the other diagonal pair of slings. Not recommended because the load tends to twist during lifting.
2) Position the two slings at the one end of the object in the center of the hook, sandwiched between the two slings for the other end of the object. Recommended method.