Sucker rods are threaded on each end and manufactured to dimension standards and metal specifications set by the petroleum industry. Basic components are barrel, plunger, valves, and hold-down. Two types of sucker rod pumps are the tubing pump, in which the barrel is attached to the tubing, and the rod, or insert, pump, which is run into the well as a complete unit. See suction tank. Also called a suction pit.
Some states require a minimum length to protect freshwater sands.
Compare conductor pipe. It is caused by the cohesive attraction between the molecules of liquid. The use of surfactants permits the thorough surface contact or mixing of substances that ordinarily remain separate. Surfactants are used in the petroleum industry as additives to drilling mud and to water during chemical flooding. Also called spurt loss.