A derrickhand or derrickman is the person who sits atop the

derrick A derrick is a lifting device composed at minimum of one guyed mast, as in a gin pole, which may be articulated over a load by adjusting its guys. Most derricks have at least two components, either a guyed mast or self-supporting tower, and ...

on a

drilling rig A drilling rig is an integrated system that drills wells, such as oil or water wells, or holes for piling and other construction purposes, into the earth's subsurface. Drilling rigs can be massive structures housing equipment used to drill wa ...

. Though the exact duties vary from rig to rig, they almost always report directly to the driller. Their job is to guide the stands of the drill pipe into the fingers at the top of the derrick. Other duties might include monitoring pH and calcium levels, viscosity and the mud weight (

density Density (volumetric mass density or specific mass) is the substance's mass per unit of volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' can also be used. Mathematical ...

), adding chemicals and oil based fluids, and being responsible for the shale shakers and

mud pump A mud pump (sometimes referred to as a mud drilling pump or drilling mud pump), is a reciprocating piston/plunger pump designed to circulate drilling fluid under high pressure (up to ) down the drill string and back up the annulus. A mud pump is an ...

Details

The name derrickhand comes from the position they typically occupy, which is at the top of the

. From this position they guide the stands of drill pipe, typically 90 feet (27 meters) long, into the fingers at the top of the derrick while tripping (removing the drill string) out of the hole. When tripping into the hole (or "running in") they will pull the pipe out of the fingers and guide it into the elevators suspended from the top drive. Traditionally, the derrickhand also works closely with the mud engineer (see

drilling fluid In geotechnical engineering, drilling fluid, also called drilling mud, is used to aid the drilling of boreholes into the earth. Often used while drilling oil and natural gas wells and on exploration drilling rigs, drilling fluids are als ...

) when not tripping pipe since they are not needed in the derrick. In this capacity it is their responsibility to monitor pH and calcium levels, viscosity and the mud weight (

), adding sacks of chemicals (25-100 lb each) to the mud or oil to maintain the desired properties, and monitor the mud level in the mud pits to aid

well control Well control is the technique used in oil and gas operations such as drilling, well workover and well completion for maintaining the hydrostatic pressure and formation pressure to prevent the influx of formation fluids into the wellbore. This te ...

. They are also responsible for the shale shakers and mud pumps (making sure they run well and fixing them as needed). The derrickhand is also responsible for the transfer of additional fluids or chemicals (e.g.: Barite, Bentonite or oil-based fluids) from bulk silos or tanks (tank farm) to the mud system. Resource extraction occupations Petroleum production Oilfield terminology {{oilfield-stub