OIL-WELL SUCKER-ROD PUMP UNIT Russian patent published in 1999 - IPC

FIELD: lifting oil from well, mainly high-viscosity oil by means of drive of pumping unit. SUBSTANCE: pump cylinder is enclosed in pipe casing inside which circular space is formed; delivery valve unit is arranged in lower portion of circular space; valve unit consists of spring-loaded gate, seat and sub. Pipe casing is secured to delivery valve body at one end; at other end it is secured to coupling of first lifting tube. Attachment of pipe casing is effected by means of adjusting screws. Lower portion of pump cylinder is passed through seat and is secured in center of sub. Wall of delivery valve seat is provided with passages for flow of liquid; these passages coincide (in shape) with liquid passages in sub. Sum of areas of straightway passages in seat and in sub separately is equal to or lore than area of plunger. Area of liquid straightway passage in circular space is also equal to or more than area of plunger. Provision is made for reception of mechanical admixture settling in inner cavity of plunger. Plunger is provided with receiving ports at the top and with plug at the bottom. Inner surface of delivery valve body is provided with longitudinal and transversal grooves within stroke of spring-loaded gate. These grooves are intersecting; they are used for accumulation and removal of mechanical admixture from clearance between gate and body of valve. EFFECT: enhanced efficiency due to increase of area of straightway passages in pump to cross section of plunger. 44 cl, 4 dwg