Derrickhand
The Derrickhand or Derrickman position varies greatly from one drilling rig to another. He almost always reports directly to the driller. The name derrickman comes from the position that he normally occupies, which is at the top of the derrick. From this position he guides 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) he will pull the pipe out of the fingers and guide it into the elevators suspended from the top drive. Traditionally, the derrickman also works closely with the mud engineer (see drilling fluid) when not tripping pipe since he is not needed in the derrick. In this capacity it is his responsibility for monitoring the pH level, level of Calcium, viscosity and the mud weight (density), 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 in the well control. He is also responsible for the shale shakers and the mud pumps (making sure they run well and fixing them when a fault occurs). The derrickman 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.