Overhead cranes, sometimes called bridge cranes, are a staple in many shop environments and are among the most heavily used pieces of equipment. Unfortunately, familiarity can breed complacency and overconfidence upon the part of operators and lead to unsafe operating practices.
Sadly, accidents are often the end result of user carelessness. However, accidents can often be prevented by increasing awareness among crane users about dangerous practices. Below are three ill-advised overhead crane operating practices that should be avoided.
Reliance on Safety Devices
Modern overhead cranes contain numerous safety devices that help protect workers from injury. Unfortunately, relying upon safety devices instead of practicing safe operating habits is a prime cause of accidents.
As an example, many overhead cranes contain upper limit switches. These switches are designed to shut down drum rotation during hoisting as a means of preventing the hook from being pulled into the drum mechanism. Some crane operators routinely utilize upper limit switches instead of manually controlling the hoisting process. Should this safety switch fail during a hoist, the hook and load will collide with the drum and cause the load to fall.
Another safety mechanism in overhead cranes is load braking. These devices prevent the uncontrolled release of a load during hoisting. However, many load brakes only slow the rate of descent, not stop it completely. Relying upon a load brake to prevent a crushing injury is simply unwise, and unwary workers below can still be killed by a load descending at a reduce rate of speed. That means keeping workers from entering the space beneath loads is still as important as ever, even when overhead cranes are equipped with load braking.
Failure to Inspect
Another unsafe working habit to adopt when operating overhead cranes is the failure to inspect equipment. It is mandated by law to inspect cranes on a daily basis, and this is for good reason. Crane problems can occur during any shift, and a failure upon the part of a previous shift to notify a subsequent shift can be fatal if inspection isn't a regular part of daily duties. In addition, such failures can occur without anyone's knowledge and will manifest themselves during operation at the next available opportunity.
Inspection doesn't need to be a complex, cumbersome matter. In fact, it mostly involves using the senses of sight and hearing to check for anything out of the ordinary. When inspecting an overhead crane, take note of unusual sounds, such as grinding or hissing, and be on the lookout for out-of-the-ordinary sights, such as leaking fluids or missing components. Also, be sure to check written maintenance logs and records on a daily basis; you may spot an entry that can alert you to possible operational dangers.
Exceeding Crane Capacity
Another dangerous operating practice is overloading the crane. There is a false assumption among some crane operators that crane capacities are only advisory. Unfortunately, this assumption can lead to terrible accidents, such as load drops, wire or chain breaks, and even collapsed support structures.
Always know how much a given crane can safely lift before using it. Capacities are not a secret, but don't make any assumptions about a crane's hoisting ability. Also, accurately measure loads before hoisting them. Knowing a load's exact weight is vital to making a safe lift, so use whatever equipment is necessary to weigh a load if specifications aren't readily available.
In addition, there are load weight-measuring devices that can be incorporated into hoists; these are valuable for providing fast checks on the weight of objects and can make preventing accidents much easier. However, keep in mind that no device can substitute for research ahead of time and the use of conservative hoisting practices.
Follow this hyperlink to learn more about industrial crane operation.