Sucker Rod

This is an artificial-lift pumping system using a surface power source to drive a downhole pump assembly. A beam and crank assembly creates reciprocating motion in a sucker-rod string that connects to the downhole pump assembly. The pump contains a plunger and valve assembly to convert the reciprocating motion to vertical fluid movement.

A sucker rod is steel rod that is used to make up the mechanical assembly between the surface and downhole components of a rod pumping system. Sucker rods are 25 to 30 ft [7 to 9 m] long and threaded at each end to enable the downhole components to be run and retrieved easily.