GB837847A - Deep well reciprocating pump - Google Patents

Abstract

837,847. Deep well pumps. U.S. INDUSTRIES Inc. May 16, 1957, No. 15593/57. Class 102 (1). A structure for anchoring pumps in tubing in a well comprises a tubing extension 20, secured on to the end of a tubing string 15, which includes a cross-over connection 40 to which is secured a seating nipple 61. The seating nipple includes a lower bore 65 of a smaller diameter than an upper bore 68 and a seat 66. The pump unit comprises two separate pumps which pump liquid from two separate zones, these liquids being themselves kept separate, and includes a seating body 52 carrying upper and lower sealing rings 70, 71. When the pumping unit is inserted in the tubing the body 52 engages the seat 66 and the sealing rings engages the bores 68, 65. Liquid pumped from the lower zone passes through passageways 56, 64, 51 and the hydrostatic head acts on the sealing rings, which due to their differential areas, causes a downward force to anchor the pump unit. The lower pump comprises a cylinder 98 which reciprocates over a fixed piston 99 and pumps liquid from an inlet pipe 102 to the passageway 56 and hence to the surface. The upper pump comprises a reciprocating piston 80 which draws liquid from inlets 26 in the crossover connection, past valve 87 to the chamber 85 and delivers the liquid past valve 82 to the surface. The complete pump unit can be withdrawn as a single unit by exerting sufficient pressure against the anchoring means. The tubing extension is housed in the usual wellbore casing 11 provided with inlets 14 for the liquid to be pumped and suitable packings 21, 22 to maintain the liquids separate.