Cramp
A common name for any device for holding two or more articles together--as a flask-clamp. See CLAMP.
Crane is a hoist having the capacity of moving the load in a horizontal or lateral direction. They are classed as rotary and rectilinear, and are termed hand when operated by manual power; power, when driven by power derived from a line of shafting; steam, hydraulic, or pneumatic, when driven by steam, water, or air, under pressure carried to the cranes by pipes from a fixed source. Swing-cranes rotate, but have no trolley movement. Jib-cranes rotate, and have a trolley traveller on the jib. Column-cranes are the same as jibs, but rotate round a fixed column that supports a roof or floor above. Pillar-cranes rotate on a pillar secured to a foundation. Pillar-jib-cranes are similar to the latter, but are supplied with a jib and trolley. Derrick-cranes are similar to jibs, excepting that guy-rods hold the mast-head instead of roof-beams. Bridge-cranes have a fixed bridge across an opening, with a trolley traversing the bridge. Tram-cranes consist of a truck or short bridge, which travels longitudinally on overhead rails, but having no trolley. Travelling-cranes consist of a bridge moving longitudinally on overhead tracks, and a trolley moving transversely on the bridge. Gantries are an overhead bridge, carried at each end by a trestle travelling on longitudinal tracks on the ground, and having a trolley moving transversely on the bridge.
The overhead tramrail system of the Yale & Towne Company are a marvel of exactness and efficiency where it is desired to move loads that must be suspended during the operation. These are constructed for both indoor and outside use. The track is composed of "I" beams; special facilities are provided for curving and fitting, switches and turntables being supplied when necessary. The system thus admits of extension and use in the same manner as a surface railroad. A special form of trolley is arranged to run freely on the lower flange of the suspended track, and is provided with four wheels, two on each side, carried in a flexible frame, so that they adapt themselves to the irregularities of the track and pass easily around curves. These trolley-cranes are constructed to carry over ten-ton loads. The above-named company have done much to bring crane engineering to the high state of efficiency now attained; others also have not been slow to note the ever-increasing demands and requirements of this advanced age. The Ridgeway Balanced Steam Hydraulic Crane is a model of simplicity and effectiveness; it is attached to the ordinary steam supply, yet it is a true hydraulic crane, requiring no pumps or accumulators, and no water is consumed. The load is attached directly to the piston-rod, and the cylinder supplied with steam, water, or compressed air by a hose.
Walking cranes consist of a pillar or jib crane mounted on wheels and arranged to travel upon one or more rails. Locomotive cranes are similar to the latter, but are provided with a steam-engine and boiler capable of propelling and rotating the crane, and of hoisting and lowering the load. See IRON CARRIER.