82 RIGGING, HOISTING, and SIGNALING PRACTICES
Sling Hitches
ATTACHED AT A SINGLE POINT
ATTACHED TO DIFFERENT HOOKS
ONE SLING ONE SLING
ONE SLING
SLING ANGLE
TWO LEGS
EYEBOLT
BASKET VERTICAL MASTER LINK ATTACHMENT TWO OR MORE SLINGS
CHOKE ANGLE
CHOKE JUNCTION
CHOKER
SLING ANGLE
BRIDLE
Figure 6-7. The four basic sling hitches are different methods to attach a sling to a load.
The type of hitch used for a given application is determined by a number of factors. A load with no preexisting attachment points usually requires the use of a basket or choker hitch. Choker hitches are also used to bundle a number of pieces of material for a single lift. Basket hitches are commonly used when multiple hoist hooks are required. Both choker and basket hitches may also involve additional wraps of the sling around the load in order to shorten the effective length of the sling or to provide additional friction between the sling and the load. Care should be taken that the wraps of the sling body do not cross and create a pinch point, which would reduce the strength of the sling. For web slings, the additional wraps of the sling may overlap but should not cross.
Vertical Hitches The vertical hitch is the simplest rigging arrangement. One end of the sling is connected to a hoist hook and the other end to a load. See Figure 6-8. The vertical hitch allows the use of the full rated load of a sling (provided the attachments to the hook and the load are properly made) because there are no horizontal forces affecting the sling. However, a vertical hitch requires some type of attachment point on a load, such as a ring, an eyebolt, or a lug. The use of a single vertical hitch is more likely than other hitches to result in an unstable load, particularly with wide loads, unless the attachment point is considerably higher than the load’s CG. Any unbalance or