DRAIN VALVE Russian patent published in 2025 - IPC E21B34/06 E21B34/10 F16K17/40 

FIELD: oil industry.

SUBSTANCE: invention relates to oil industry, in particular, to drain fluid from tubing string during their lifting in process of underground repair. Drain valve includes a body with a projection and a central radial hole, an external main and an internal safety membrane, between which there is an intermediate support ring with a side hole. In the centre of the projection there is an inclined channel made in the form of a cavity of a shut-off valve with a seat and a ball. Inclined channel communicates with side opening. Inclined channel is made in the lower part of the housing projection and is equipped with an additional ball and a seat limiter. Inclined channel from the outside is covered with a metal mesh rigidly fixed to the housing.

EFFECT: increased reliability of the drain valve due to tightness of the shut-off valve, retention of various deposits or mechanical impurities and exclusion of their ingress into the inclined channel.

1 cl, 1 dwg