OIL WELL PUMPING UNIT Russian patent published in 1999 - IPC

FIELD: oil-well pumping units; well completion by direct and back flushing at one running-in and one process without killing wells and pulling-out the tubing strings. SUBSTANCE: oil-well pumping unit includes tubing string 1, box-type sub 2, pin-type sub 3 and jet apparatus 4 mounted between them (between 2 and 3); jet apparatus includes split housing 5 with longitudinal passages 6 for delivery of passive medium, stepped insert 7 mounted in housing 5 including inlet diffuser 8, active nozzle 9, mixing chamber 19, diffuser 11 made in form of change bushes and packer 12. Upper and lower stages of insert 7 have through slots 13 and 14 and suction holes 15 in center portion. Housing 5 has bores which form (together with stepped insert 7) inlet chamber 16, main suction chamber 17 and reserve suction chamber 18. Upper portion of housing 5 has longitudinal holes 19 and angular delivery passages 20 under reserve suction chamber 18. Lower portion of housing 5 is provided with additional longitudinal passages 21 for delivery of passive medium. Box-type sub 2 is provided with spacer bush 22 fitted with lock 23 which is connected with stepped insert 7 by means of threaded joint; it includes body 24 with through slots which are used for receiving spring-loaded stops 26. Suction holes 15 are located opposite main suction chamber 17 during direct flushing and opposite reserve suction chamber 18 during back flushing. EFFECT: possibility of completing wells both by direct and back flushing at one running-in of pumping unit and one process without killing the well and without pulling-out tubing string. 2 dwg