• There are many different crane rigging methods used to attach loadscranes image by FJ Medrano from Fotolia.com
  
  Rigging on a crane is an attachment that lifts a load safely. This rigging material can use several different methods and types of attachments to lift a load with a crane. There are metal mesh slings, wire rope slings, steel chain slings, synthetic slings and specialty devices or attachments made to lift a specific load. The crane operator is responsible for knowing what type of method to use when lifting a load.
  
  

Choking or Single-leg Method

• The most common crane rigging method is the choking or single-leg method. This method is done with a single leg sling which is wrapped around a load and slid through the eye of the sling, choking it tightly around the load. Knowing the center of gravity when using this choking method is important because the load can tilt and slip out of the sling. This method is primarily used on lighter loads which can easily be controlled, because of the hard time most riggers have in determining the center of gravity of the load.
  
  

Two-leg Method

• The two-leg method of rigging the load onto a crane requires the load to be attached at two different points with two single leg slings or a two-leg sling. The load is attached at a point on each end of the object or load being lifted, making a triangle shape. This method is used on long slender loads such as pipes or construction material. It does not require the crane operator to know the center of gravity and is much safer than the choke method because the load is more stable when being lifted to a new location.
  
  

Three-leg Method

• The three-leg method used to rig loads to a crane is a common method used when lifting large circular objects or loads that have unusual shapes where the center of gravity is hard to determine. A three-leg sling is used at three different attachment points to ensure the load remains stable and does not overload and break one leg of the sling. Using the three-leg method is also one of the safest ways to rig a load to a crane because the weight of the load is equally distributed among three different points. If one point or sling leg breaks, the load does not fall to the ground.