Crane trucks are a complex but useful piece of equipment that can be used to lift heavy and unwieldy objects. A crane truck has a boom with several sections that telescope together. Reinforced steel cables run from behind the cab up and over the boom-the more lines, the higher weight load can be lifted. (A heavy metal ball keeps the lines taut when the crane is not lifting a load.) Beneath the cab is a large gear that enables the crane truck to maneuver 360 degrees. The gear is driven by a hydraulic motor on the cab and is controlled by the operator via a foot pedal. Crane trucks are frequently used in construction, transportation, utilities, mining, drilling for oil, railroad yards, heavy equipment yards and building supply dealers. Crane trucks can be custom ordered and assembled with different specifications that suit the buyer, be it the size of the engine or the length of the boom.
Here are some tips on how to use crane trucks:
- One of the biggest hazards of operating a crane is the possibility of electrocution. When working near overhead power lines, employers, supervisors, and workers must exercise extreme caution. Preventing Electrocutions of Crane Operators and Crew Members Working Near Overhead Power Lines, a publication of the National Institute for Occupational Safety and Health, provides a sobering look at this possibility and discusses how to prevent it.
- And not to dwell on the hazards, but be aware that occasionally trucks are fitted with boom cranes when they have not specifically been designed for such applications. Fortunately, the Occupational Safety and Health Administration (OSHA) is watching out for you and discusses this danger in this Hazard Information Bulletin.
- Outriggers are a very important component of crane stability: Outriggers must always be set up properly on a solid foundation. The outriggers use hydraulics to lift the truck off of the ground.
- Counterweights must be placed beneath the crane cab to prevent the crane from tipping forward. The weight of the counterweights is adjusted according to a formula that includes the boom radius, the weight of the load and the angle the boom is operating at. The crane operator must be able to use mathematical charts to calculate the appropriate counterweights.
- Most cranes have onboard computers that the operator enters information into to determine if he is operating the crane according to manufacturer specifications. The computer is meant to be more of a back-up system to alert the driver if he is exceeding the load limits of the crane truck he is operating.
- Load moment indicator lights will turn on if the crane's operating capacity is being approached. The load needs to be reduced if these lights go on.
- Crane operators maneuver both foot petals and joysticks to control movement of the boom both left to right and forward and back. The foot petals control the telescoping aspects of the boom as well as the pump pressure. Crane operators also control the winding and unwinding of the winch, and any rotating of the cab. All controls should be labeled.
- Don't skimp on crew. Two other workers are necessary for the safe execution of a lift-the oiler and the signalman. The oiler is in charge of the crane's parts while the signalman is what he sounds like-the man who gives hand signals to the crane operator as he performs the lift.