Tubing pumps are classified as high volume, heavy duty pumps.
Maximum production can be expected with this type in relation to the size of tubing. However, because of the large plunger diameter, the fluid load will be greater than with an insert pump. Therefore, the depth at which a tubing pump can be run depends on the rod string and size of the surface pumping equipment.
The pump barrel serves as a section of the tubing. The plunger and traveling valve are run in the well with the sucker rods.
The standing valve can be one of two types:
The fixed type is attached below the pump barrel as part of the tubing string. A larger valve can be installed than with a retrievable type but the tubing must be pulled in order to repair it. When barrel repairs are required on a tubing pump, the entire tubing string must be pulled.
The retrievable type standing valve rests in a cup-type or mechanical type seating nipple at the bottom of the pump barrel. It can be removed with the sucker string by means of a valve puller which is permanently attached to the lower end of the plunger.
Pumps are available in different lengths and material to address the different downhole challenges.