FIELD: oil production; plants for pumping emulsion oils and gas-and-liquid mixtures out of deep oil wells. SUBSTANCE: proposed unit includes tubing string with liner and sucker-rod insert pump with main suction valve. Tubing string has bearing taper seat where cylinder of sucker-rod pump is mounted by its mounting taper surface. Radial holes and passage are used for communicating the cylinder cavity with additional suction valve. EFFECT: increased production of oil; increased service life of oil-well equipment. 2 cl, 1 dwg
