A drilling rig is used to drill a hole in the earth's subsurface to a set depth. In the oil and gas industry, drilling rigs are used to drill oil wells, gas wells and water wells. Larger drilling rigs are classified as singles, doubles or triples. A single means that the derrick holds a single length of drill pipe. A double holds a two lengths of drill pipe and a triple holds three lengths of drill pipe.
Smaller rigs can mobile which means they are mounted on trucks, tracks or trailers. The larger onshore drilling rigs used to drill oil and gas wells are shipped in pieces and constructed onsite with cranes. Some of newest drilling rigs used in the shale oil & gas industry can 'walk' small distances from one dill hole to the next. Offshore drilling rigs are mounted on platforms. These platforms are moved into place by boats.
The main components of a drilling rig used to drill oil & gas wells include:
- Mud tanks
- Mud pumps
- Derrick / mast
- Rotary table / topdrive
- Drill String
- Power generation equipment
- Auxillary Equipment
Onshore vs. Offshore
Both onshore and offshore drilling rigs utilize the same equipment. However, offshore drilling requires a platform. The platform may be a floating platform or fixed platform. Fixed platforms are supported by the sea bed.
1. Drilng Rig - Schlumberger Oilfield Glossary. Retrieved from http://glossary.oilfield.slb.com/Terms/d/drilling_rig.aspx