DERRICK CRANE MODEL

Derrick Crane Model



Derrick Crane Model

This apparatus represents the forces in a simple crane and introduces the student to equilibrium of forces and solution by the triangle of forces.

The crane is mounted on a base designed to be stood on a level bench.

Both the jib and tie include spring balances for measuring the internal forces. A load is hung from the end of the jib. (Matheus, 2009)

Re-adjustment of the crane geometry back to its original unloaded layout is possible by a knurled adjuster on the jib and adjusting the links of the chain.

This equipment is part of a range designed to both demonstrate and experimentally confirm basic engineering principles. Great care has been given to each item so as to provide wide experimental scope without unduly complicating or compromising the design. Each piece of apparatus is self-contained and compact. Setting up time is minimal, and all measurements are made with the simplest possible instrumentation, so that the student involvement is purely with the engineering principles being taught. A complete instruction manual is provided describing the apparatus, its application, experimental procedure and typical test results. (O'Connor, 2009)

Cranes and derricks are utilized for lifting service across a wide spectrum of operating conditions. They may be exposed to infrequent duty, as in power plant turbine house service where passive work— maintenance and testing—is the usual use and productive working lifts are occasional, or they may be punished by intense use such as in steel mill service where round-the-clock operations induce millions of loading cycles. The assortment in forms, environments, and operating regimes makes the selection and installation of hoisting equipment an artful skill that is critical to a successful project. An ever-present concern whenever cranes and derricks are at work is safety. By their nature, rigging and lifting loads entail risk, and when accidents occur, they are almost always dramatic and newsworthy. Safety is an abstract notion. The term is easily used in discussion or writings, but the actuality is not always easy to achieve in practice; there are few simple fixes and no panaceas(Lancaster, 2009) . Devices intended to enhance safety may yield no benefit in actual use, or even have a contrary effect. What may improve safety under one set of circumstances can have negative effects under another. In many situations, the most effective safety enhancements are small and subtle measures tailored to the risks associated with the particular operation. ...