Hoisting Systems

Wire Rope. The size and type of wire rope shall be as specified in API Specification 9A and by API RP 9B (see section titled Hoisting System ). 

A hoisting system, as shown in Figure 4-8, is composed of the drawworks, traveling block, crown block, extra line storage spool, various clamps, hooks, and wire rope. 

Normally, a hoisting system has an even number of working lines between the traveling block and the crown block. The fast line is spooled onto the drawworks hoisting drum. The dead line is anchored to the rig floor across from the drawworks. The weight indicator is a load cell incorporated in the dead line anchor. 

Figure 4-8. Schematic of simplified hoisting system on rotary driiling rig [9].

The mechanical advantage of the hoisting system is determined by the block and tackle and the number of working lines between the crown block and the traveling block [7]. 

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