DRAIN VALVE FOR DRAINING LIQUID FROM PUMP STRING Russian patent published in 2018 - IPC E21B34/14 F16K15/06 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to the petroleum industry and is intended for draining liquid from a string of pumping pipes before lifting them out of a well. Drain valve for draining liquid from the pump string contains a ball, a branch pipe with a hole, a connection connected in the opening of the branch pipe with a thin part of a two-stage nozzle. Hollow cylinder is connected to the free end of the thick part of the two-stage nozzle. It is made with a chamfer at the lower end of the inner side wall. Hollow cylinder is equipped with spring loaded compression spring with a rod. At the lower end of the rod there is a protrusion in the form of a truncated cone. Washer fixed with a screw wrapped in a radial threaded sampling made on the rod above the washer is at the top of the rod above the compression spring. In this case, the stem is formed integrally with a rod having a conical frustum projection at its lower end.

EFFECT: technical result consists in improvement of reliability of valve.

1 cl, 2 dwg