Drawworks

Drawworks, or draw works, are the hoisting units used on drilling rigs to raise and lower the drill string, casing, and other loads. The core component is a large hoisting drum around which a steel drill line is wound. The drum is typically driven by a prime mover—an electric motor on most modern land rigs or a diesel engine on some offshore units—through a reduction gear train. A brake system, usually consisting of band brakes, holds the load, while a clutch allows engagement and disengagement of the drum. The drill line is wound onto or unwound from the drum as needed to raise or lower the load. The line is routed between the drum and the rig’s top block assembly (crown block and traveling block) to the drill string and hook.

Operation and control are conducted from the drawworks control system, where the operator adjusts line speed and load via the hoist controls. Safety devices, including limit switches, emergency stops, and load-monitoring systems, are integrated to prevent overtravel or overloading. The drawworks works in conjunction with the rig’s rotary system, which may be a rotary table or a top drive, to rotate the drill string while the drawworks handles up-and-down movement.

On modern rigs, drawworks may be electric- or diesel-powered and are often integrated with automated controls and monitoring. They are designed for high reliability, with routine maintenance focusing on the drum winding layers, line wear, brake adjustment, lubrication, and gear oil levels. The drawworks remains a central component of surface drilling equipment, enabling controlled hoisting and lowering during drilling operations.