Chapter 9 - Hydraulic Pumps

Abstract

This chapter provides an overview of hydraulic-powered downhole pumps, which are powered by a stream of high pressure power fluid supplied by a power fluid (PF) pump at the surface and sent to a downhole pump or pump engine. Hydraulic pumps are basically of two types—piston downhole pumps that are similar to beam down-hole pumps, and jet downhole pumps that reduce the pressure on the formation by high-speed power fluid flow through the throat of a venturi or jet pump nozzle-diffuser combination. Hydraulic pumps can be used to remove liquids from gas wells. A skid-mounted hydraulic pump can be used to kick off a gas well and then be moved to another well for testing, production, or longer term de-watering. Hydraulic pumping is generally not depth limited, and deviated or crooked wells do not present problems. Hydraulic reciprocating pumps can produce a low bottomhole pressure. A jet pump may require a fluid height over the pump of 20% of submergence. A jet pump is more trouble-free than a reciprocating hydraulic pump and can tolerate some solids in the production. Fairly high rates of more than several hundred bbls/day are possible. In general, hydraulic systems are not rate limited when removing liquids from gas wells.