Glossary

A triangular structural frame that supports the topping lift on cranes and derricks; in some instances, it can act as a jib strut

A type of wire-rope construction in which the strands are alternately regular lay and lang lay

The angle that the surface of a material in a freely formed pile makes to the horizontal

The angle that the surface of a material takes when it is at rest on a moving conveyor belt as measured from the horizontal

A set of devices that assist in preventing tower-crane booms and suspended loads on two or more cranes from fouling each other

A crane with a boom composed of a series of folding pin connected elements, manipulated by hydraulic cylinders

A secondary crane used to help assemble a larger crane or to perform lesser tasks such as unloading trucks and shaking out hardware

The rate averaged over a relatively long period of time. For example, the number of products that go past a specific point in the system during an hour divided by 60 would be the average rate in CPM. Averaging can also be done over a full 8-hour shift. The average capacity is almost always less than the design capacity. This is caused by a variety of conditions such as a lack of product or inefficiencies of workers loading the system

The vertical line about which a crane or derrick swings. This is the centerline around which the crane’s superstructure revolves. Also called Center of rotation and Swing axis

Resistance to overturning of the crane in rearward direction