Figure 1-12. - Bridles.
on one end and a pelican hook on the other.
There is also available a 3/4-inch (19.05-mm) chain sling, 22 feet (6.6 m) long, with a grab hook on one end and a Cinch (100-mm) link on the other.
Before doing any lifting with a chain sling, first place dunnage between the chain and the load to provide a gripping surface. In handling rails or a number of lengths of pipe, make a round turn and place the hook around the chain as shown in figure 1-13.
In using chain slings, you must exercise care to avoid twisting or kinking the chain while it is under stress. This condition might cause failure of the chain, even in handling a light load. Before lifting, make sure that the chain is free from twists and kinks. Make sure, also, that the load is properly seated in the hook (not on the point) and that the chain is free from nicks or other damage. Avoid sudden jerks in lifting or lowering the load, and always consider the angle of lift when using a sling chain bridle.
Store chains in a clean, dry place where they will not be exposed to the weather. Before storage, it is a good idea to apply a light coat of lubricant to prevent rust.
Makeshift repairs, such as fastening links of a chain together with bolts or wire, should never be permitted. When links become worn or damaged cut them out of the chain; then fasten the two adjacent links together with a connecting link. After the connecting link is closed and welded, it will be as strong as the other links. For cutting small-size chain links, use bolt cutters. For cutting large-size links, use a hacksaw or oxyacetylene torch.
Slings must be inspected frequently and removed from service whenever defects are detected. Bear in mind that a defective sling may cause serious injury to personnel or extensive damage to equipment in case of failure under load.
You should check FIBER-LINE slings carefully for signs of deterioration caused by exposure to the weather. You should also check closely to determine whether any of the fibers have been broken or cut by sharp-edged objects.
Broken wires are a major defect to look for when inspecting WIRE-ROPE SLINGS. When four percent of the total number of wires in the rope are found to have nicks, or cuts, they should be replaced. However, if a chain shows evidence of stretching or distortion of more than five percent in any five-link section, make sure the entire chain is discarded.
Figure 1-13. - Chain sling.Continue Reading