CASING STRING BOTTOM EQUIPMENT Russian patent published in 2020 - IPC E21B33/14 E21B33/16 

FIELD: oil, gas and coke-chemical industries.

SUBSTANCE: invention relates to oil and gas industry, in particular, to casing string bottom equipment. Casing string bottom equipment includes a valve and a plug. Valve comprises drilled body, through channel made in drilled body, ring, rotary clamp, spring, polyethylene bushing, aluminium ball. Passage channel is made with the possibility of closing by means of a rotary clamp by means of a spring. In the lower part of the bushing there are slots forming a throttling hole. Proposed plug comprises at least one rubber sleeve and aluminium rod. Rubber collar is installed on aluminium rod and fixed on it by means of at least one nut. On the lower end of the aluminium rod there installed is a tip, a sealing ring and a retainer in the form of a split annular spring. Valve and the plug are equipped with a fixation mechanism with each other including projections on the plug tip crosswise, and slots on the cone-shaped valve surface, also located crosswise.

EFFECT: technical result is exclusion of plug rotation during drilling, facilitation of drilling process, reduced time of well construction.

1 cl, 4 dwg