Sand-Tolerant Pump

When producing in sandy wells with reciprocating rod-lift systems, wear can occur at unacceptable levels. Abrasive sand accumulating within the barrel/plunger interface damages both the barrel and the plunger, thereby shortening pump life, reducing production rates, and increasing operating costs. The Weatherford sand-tolerant pump (STP) restores economic viability to sandy rod-pumped wells. On the basis of ongoing tests, the STP works in sandy conditions more than six times longer than conventional rod pumps by lubricating the plunger/barrel interface with filtered production fluid. The STP features a wiper assembly and filter coupling for efficient, reliable performance. The outside of the wiper assembly creates a barrier that keeps sand out of the plunger/barrel interface by continually wiping the inside of the barrel while the pump produces sandy fluid to the surface. The filter coupling houses an internal screen that allows only clean produced fluid to pass through the equalization ports to the interface and lubricate the pumps. Because the filters move with the plunger, the sweeping action of the fluid on the downstroke cleans the filters and keeps sand suspended within the production fluid. The sand-laden fluid is then produced through the center of the plunger to the surface.

On the basis of recent data, Weatherford’s STP offers six times the run life of conventional rod pumps in sandy, rod-pumped wells.