Instructions for Crane Chain Slings
July 31, 2014
Before lifting an object, choose correct slings first, including such parameters as leg(s) of chain slings, diameter of slings, and working load limit (WLL). For multi-leg chain slings, the operator must know about the working load limits at different angles.
When using the crane chain slings, the operator must follow the laws and regulations as well as relevant safety standards of crane lifting operation.
● The slings must not be twisted or knotted.
● Do not drag the slings from under the load.
● When the slings are encircling the edges of the object, remember to cushion the slings. Otherwise they may be damaged.
● To prevent the load from being impacted or imbalanced, use a regulator when necessary.
● When using the hooks, the load should be applied to the lowest point of the hook slot. Never apply the load directly onto the hook tip.
● Never use chain slings in acid solution or gaseous environment, or it may cause corrosion of the slings or lead to brittle mechanism and cracks.
If the operator must use the slings in such environments, consult the chain sling manufacturer.
● Without permission of the chain sling manufacturer, do not dispose the chain slings in any of the following ways: zinc galvanizing, electroplating, coating, heating, or acid pickling.
● When hoisting important or dangerous objects, professionals must conduct risk assessment and adjust the working load limit accordingly.
To make sure that the lifting load is not twisted or overturned, the operator must comply with the following rules:
● When using single-leg chain slings, the contact point should be vertically above the gravity center of the load.
● When using double-leg chain slings, the contact points should be on both sides above the gravity center of the load.
● When using triple-leg or quadruple-leg chain slings, the contact points should be evenly distributed above the plane around the gravity center of the load, and the chain slings are preferably evenly distributed.
● When using multi-leg chain slings, please select proper kind and contact points of chain slings, so that the dip angles (β) of sling legs are within the permissible range. The dip angles are preferably the same, and the dip angles below 15° (β<15°) must be avoided.
