A drawworks is a machine on a rotary drilling rig that raises and lowers the drill string and other equipment in a well. It’s made up of a large drum, a power source, brakes, and other components.
How it works
- The drawworks drum reels in and out a thick wire rope called the drilling line
- The drilling line goes over the crown block at the top of the rig and down to the traveling block closer to the ground
- Turning the drum raises or lowers the traveling block, which controls the drill string
- Gravity helps lower the drill string when the drum isn’t powered
- An electric motor or diesel engine reels in the drilling line
- Brakes control the movement and stop the drill string
Benefits
- The drawworks uses a block and tackle or pulley system to gain mechanical advantage
- The routing of the drilling line multiplies the pulling force of the drum
