Gas locking Prevention pump

Gaseous-fluid pumps are designed to increase the efficiency of pumps in high
gasto-liquid ratio (GLR) wells.

The stationary part of the gas-fluid pump consists of a short barrel and an
extension, forming a chamber between them. The plunger is long enough to bridge
the chambers and create a seal during the pumping cycle. The plunger moves
completely in and out of each pump barrel throughout the cycle. During the
upstroke, the turbulence and low pressure cause the gases in the fluid to
expand, separate and rise to the top of the suction chamber. In the previous
pump cycle, the fluid in the intermediate chamber was pressurized after
contacting the total liquid column. The remaining gas in this fluid is under
pressure and the gas to liquid volume ratio is lower than the volume ratio of
the fluid entering the pump.

During the downward stroke, the free gas rises towards the top of the
chamber. As the plunger continues downward, gas and liquid are trapped in the
intermediate chamber. When the fluid below the swimming valve is expelled, the
valve opens, allowing gas and fluid to flow up through the plunger. When the
plunger is near the bottom of the stroke and the chamber is open at the top, the
trapped gas escapes and rises through the fluid. When the chamber is closed
again on the upstroke, the fluid gas content in the chamber has been reduced to
a minimum

Proper valve spacing minimizes the clearance between the stroke valve and the
fixed valve, thereby maximizing the compression ratio and increasing the total
volume of fluid delivered per stroke. Gas-fluid pumps are primarily assembled
from API type RH components and are supplied in API cups or API mechanical
holddowns.

Because the chamber of the gaseous fluid pump is too large, it is not
recommended for oil wells that contain a lot of sand or solids, which are prone
to sand sticking.