Preventing Gas Locking in Sucker Rod Pumps using an Actuated Traveling Solenoid Valve

Abstract

Abstract Gas locking has been a problem accompanying the ball and seat Sucker Rod Pump ever since its inception in the oil industry. A gas lock occurs when, contrary to the normal functioning of an SRP, due to a gas influx from the standing valve, the pressure exerted by the fluid below the traveling valve in the closed chamber does not overcome the weight of liquid column lying above the traveling valve in the pump barrel. This fails to lift the ball off the seat. This paper brings forth the design of a Sucker Rod Pump consisting of a solenoid actuated hydraulic valve in the traveling plunger seat to address this failure. The traveling section contains a hydraulic valve in the plunger seat in conjugation with a solenoid actuator at the surface for executing an open or close mode. The electric supply for the valve is provided through a wire conduit in the polish rod connected to a control system installed at the surface. A sensor is placed to sense the event of beginning of each, up as well as down, stroke of the plunger. Based on this trigger, at the beginning of every down stroke, the solenoid is set on to provide power for the valve to open. This external drive for the valve opening compensates for the negative variation in magnitude of the fluid pressure differential between the traveling and standing sections, thus enabling fluid intake into the pump barrel. When the end of the stroke is sensed, the hydraulic valve piston is seated back for the valve to close. This enables the lifting of the fluid in the pump barrel during the upstroke. This design aims at latency free synchronization of the valve opening and closing with pump reciprocation under circumstances of gas interference. From first principle, this mechanism of voluntarily open the traveling valve during the downward motion would prevent the problem of gas lock. This would also increase the efficiency by eliminating non producing compression strokes which are also a cause for pump breakdown.