GB724446A - Hydraulic subsurface motor and pump combination - Google Patents

Abstract

724,446. Valve gear for fluid-pressure engines. UNITED STATES STEEL CORPORATION. March 16, 1953 [March 27, 1952], No. 7229/53. Class 122 (2). [Also in Groups XXVIII and XXIX] A motor and pump combination, particularly for a deep well, comprises an hydraulic motor piston 25 operating in a cylinder 22 connected by a coupling, forming a chamber 28, to the pump barrel 15. The piston 25 is connected to the pump bucket 18 by a hollow rod having portions 30a and 30b of different diameters. A hollow rod 26 extends through the cylinder head 23 into the pipe 12 for the pressure liquid supply and the piston 25 contains main distributing valves controlled by auxiliary valves from which stems 35 extend on either side of the piston. Fig. 2 shows the arrangement at the upper end of the piston in which the stem 35 abuts a collar 32 on the reduced portion 34 of the piston so that the auxiliary valves are actuated when the collar 34 engages the cylinder head 23; the arrangement on the lower side of the piston is similar. The pumped liquid passes through the bucket valve 19 and port 31 to the chamber 28 and then through port 29 to the well tube 10 above the packing 21; the motor also exhausts through port 31 to join the pumped liquid. The space above the pump bucket is vented through port 20. Although the pump is single-acting the diameters of the piston 25, bucket 15, rod 26, and rod parts 30a, 30b are chosen so that the ratio of the effective power piston area to the total displacement area is the same on both strokes.