GB625432A - An improved apparatus for raising liquid from wells by means of gas under pressure - Google Patents

Abstract

625,432. Oil-well pumps. GILMOUR, H. June 27, 1946, No. 19232. [Class 102(ii)] A liquid displacement pump comprises an outer shell 6, Figs. 1A and 1B and 6a, Figs. 1B and 1C, a tubular conduit 16 surrounding a valve casing 24 containing pilot inlet and exhaust valves 21, 26 connected by a spindle 23 and controlling intermittent opening of a main inlet valve 13 secured to a piston 18 by a spindle 17. Gas, under pressure, supplied to the induction space A, Fig. 1A, travels by way of a port C in a housing 3 to a space F and then through ports F<SP>1</SP>, a space G and inlet ports H in the valve 13, to an axial port M in the spindle 17 thereby opening the valve 21 against the upward thrust of a helical spring 37 provided on the spindle 23. The valve 26 which is initially opened, is then closed, and the accumulated pressure within the space N forces the piston upwards thereby opening the valve 13 which in turn causes a tongue 12 secured to the valve to force open the pivoted jaws of a catch 11 against the pressure of a spring 8 until the tongue is retained within the recess in the jaws and the piston 18 held at the top of the cylinder 24. The gas is now free to flow down the annular space between the conduit 16 and the casing 24 to an annular space R, through ports S into a recess X and thence by way of a port T to a liquid collecting chamber. The liquid in the chamber is displaced by the gas through an eduction tube 36 to a port W and thence by way of an annular space E, Fig. 1B, through a port D in the housing 3 to an eduction tube B and so to the surface whereupon the pressure in the tube B falls with a corresponding fall in the spaces A, C, F and M. The valve 26 is then opened, due to the closing of valve 21 on its seat 20 by the spring 37 overcoming the gas pressure in the port M, and the space N opened to atmosphere through a passage Q and a port V. The higher pressure now existing in the space G forces the piston 18 and the tongue 12 downwards thereby closing the valve 13 and the cycle is then complete. A valve, secured to the tube 36, which allows gas within the liquid filling chamber to escape to atmosphere by way of the port W is closed against its spring by the gas pressure during the raising operation.