Car Sling - Geared
Sling The sling is the framework which encloses the cab. The ropes, guides, and platform attach to the sling (also called a car frame). The width of the sling depends on the platform width. The height of the sling depends on the cab height. A typical sling consists of: two stiles, a safety plank (called a bolster on a hydraulic equipment type), two strike plates, a cross-head, and brace rods. Let's take a closer look at each of these components. Stiles Sling = stiles, safety plank, cross-head, brace rods, strike plates. Stiles are two vertical channels, one on each side of the car, running parallel to the rails. The stiles connect to the crosshead and the safety plank. They also provide a mounting point for one end of the brace rods. The length of the stiles is based on the cab height. Safety Plank Sling = stiles, safety plank, cross-head, brace rods, strike plates Safety Plank is the bottom member of a sling for a geared traction elevator which contains the safety. The stiles connect to the crosshead and the safety plank. Cross-Head Sling = stiles, safety plank, cross-head, brace rods, strike plates Cross-Head is the name of channels running horizontally between the stiles at the very top of the sling. The cross-head on geared traction elevators is the counterpart to the safety planks. In addition, the cross-head is the attachment point for the top rail guides and hoist ropes. Remember, the cross-head on a hydraulic elevator spaces the stiles apart as a counterpart to the bolsters. The cross-head on a geared traction equipment type, on the other hand, is the load-bearing structural element of the sling. The load of the car must be considered when sizing cross-heads. Brace Rods Sling = stiles, safety plank, cross-head, brace rods, strike plates Normally, there are four brace rods. One end attaches midway up each stile and the other end attaches to a corner of the platform. Brace rods provide stability and ensure that the platform is level. Strike Plates Sling = stiles, safety plank, cross-head, brace rods, strike plates Two strike plates are attached to the underside of the safety planks. The strike plates are the contact points between the car sling and the buffer springs if the car travels too far below the lowest terminal landing. Sling Hitch The car hitch plate secures the ropes to the cross-head. Notice that the ropes are secured in the center of the cross-head. This location is unique to geared traction elevator equipment type.
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