Picture of a Well - Definitions
Casing: heavy steel pipe that lines the walls of the hole.
Cement: used to fill the space between the hole and the casing. Together with the casing, this prevents caving of the hole, prevents movement of fluids (water, oil, or gas) between rock layers, confines production to the well bore, and provides a means to controls pressure.
Counter balance: Provides for the even distribution of loads and for the reduction of peak torque requirements.
Gear box: Reduces the speed of the motor to suitable pumping speeds.
Horse head: Allows the joint where the polished rod is attached to move in a vertical pattern instead of an arc.
Motor: Provides power to the gearbox. The motor is the prime mover for the pump to work.
Oil sand: the oil reservoir, generally composed of sandstone rock.
Pitman arm: Provides vertical movement from the rotating counter balance to the walking beam.
Polish rod: Reduces unnecessary wear and friction losses at the stuffing box located at the wellhead.
Pump: Admits fluid from the producing oil sand into the tubing and lifts that fluid to the surface.
Sucker rods: Transmit movement from the surface pumping equipment to the down-hole pump.
Tubing: steel pipe of a smaller diameter than the casing, placed inside the casing string, to provide a path for the produced fluids to reach the surface.
Walking beam: Pivots near its center from motion supplied by the pitman arms causing the horse head to move up and down in near vertical movement.
Well head: Includes the stuffing box, flow line, and various valves and pipes to direct the flow of oil and gas at the surface.