In normal operation, overhead crane hoists are designed to lift an object at a vertical angle. A side pull is when a portion of the hoist acts horizontally, such as when the hoist lifts an object that has not been placed directly underneath it.
OSHA 1910.179 (n)(3)(iv) specifically states that cranes shall not be used for side pulls except when specifically authorized by a qualified person who has determined that the stability of the crane is not thereby endangered and that various parts of the crane will not be overstressed.
When I cover the subject of side pulling in my Crane Operator Training courses, I always tell my students that if someone tells them to do a crane pull, then they are not a responsible party. That’s because side pulling can be damaging to the hoist—and more importantly, it can cause a dangerous situation for any nearby personnel.
When you perform a side pulling action on a crane, you are pushing it past its mechanical limitations. The extreme amount of stress on the crane can cause a wire rope to snap—instantly and without warning. Needless to say, this could cause a very dangerous situation for any nearby personnel, as the wire rope could whip through the air; the load on the crane would swing vigorously and could potentially be dropped.
Unfortunately, side pulling is not an uncommon situation to observe. In fact, a fair portion of the damage I observe as a technician at customer sites is because of side pulling. Side pulling is also dangerous to the equipment itself. It can damage every aspect of the crane, especially the hoist/trolley. It causes the wire rope to dig into the metal of the trolley, and it can add wear to the drums.
Side pulling is like trying to use your car as a pickup truck—it’s not going to last. You will have more maintenance issues, and it will wear out quickly. If a load is lifted more than a few degrees off-center, it multiplies the stress applied to the wire rope. This is very dangerous and can cause premature rope failure.
Side pulling is an issue that starts and stops with crane operators. Crane operators need to be properly trained, and they need to retain what they’ve learned. For each and every lift, crane operators need to be aware of the dangers of side pulling and take extra care to ensure that the crane will lift vertically, not horizontally. Maintenance and plant operations managers need to be aware of these issues and work as a team to prevent safety incidents related to side pulling.