Patent GB-490659-A (GB)
Title: Method and apparatus for pumping wells
IPC: F04B9/10
Filed: 1936-11-16
Abstract: 490,659. Liquid pressure engines. TRIGGS, W. W. (Roko Corporation) Nov. 16, 1936, No. 31324. [Class 69 (ii)] [Also in Groups XXVIII and XXVI] Relates to deep-well pumps of the type in which a pump unit 53, Fig. 1, is operated by an hydraulic motor 57, supplied with liquid under pressure by a surface pump through a line 55, the liquid being distributed to the motor by a concentric liquid-operated master valve, to which operating liquid is supplied by a pilot valve in the form of a tail-rod 98, Fig. 6, on the motor piston. According to the invention, the pump is double-acting, and the master valve is of two diameters, with differential surfaces exposed to liquid pressure. The pump piston 102, Fig. 6, is connected by a rod 99 to the motor piston 97, the tail-rod 98 of which distributes operating liquid to the master valve 93. High pressure liquid supplied through the connection 59 acts constantly on the upper end of the valve 93 and is admitted to the interior of the valve, while a shoulder 150 on the valve is constantly exposed to exhaust pressure, i.e. the pressure in the pump discharge passage 116, through a port 135. In the position shown in Fig. 2a, the high pressure liquid passes through ports 133 in the valve to a passage 78, 80 leading to the lower end of the motor cylinder, while the upper end exhausts through a passage 71, which is connected by a recess 136 in the valve to the passage 135 exhausting to the passage 116. At the same time the space 86 below the valve 93 exhausts through a port 88 in a wall 85, a helical groove 137 in the tail-rod 98 and passages 139, 140. The valve then descends until its flange 147 covers the port 80, whereupon the valve stroke is completed slowly by leakage from the space 86 through passages 151, a helical groove 152 in the wall 85, the port 133 and the port 148. When the descent of the valve is completed, high pressure liquid is admitted to the upper end of the motor cylinder through ports 149 in the valve and the passage 71, while the lower end of the cylinder exhausts through the passage 80, the recess 136 in the valve and the passage 135. When the motor piston has descended, high pressure liquid is admitted to the space 86 through a groove 153 in the tail-red, the space 146 and the passage 151. The valve thereupon rises until the flange 147 closes the port 92, whereupon the valve stroke is completed slowly by leakage liquid passing through a groove 157 and the passage 151. The supply of high pressure liquid to the motor is controlled by the valve structure shown in Fig. 24, comprising a casing 175 connected to the motor by piping 60 and an inner and relatively movable part 181, carried by the high pressure piping 55. The parts can be held in three positions by bayonet joints 190, 193 As shown, a valve face 182 on the body 181 engages a seating in the casing 175 and high pressure liquid passes to the motor by passages 186, 187. Alternatively, the body 181 can be lowered and locked so that both the passages 186, 187 are covered by the bore 180, in which case the high pressure liquid escapes past the valve 182, which is open. Specification 490,726 is referred to.