CIRCULATING VALVE Russian patent published in 2014 - IPC E21B34/10 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas producing industry and it can be used for provision of hydraulic connection of annular space with tube side during process operations. The device consists of housing with radial openings; in the axial channel there is narrowing and installed hollow step-type rod with combined sealing equipped with thrust and collar in the upper part, with a row of longitudinal openings covered in the upper part by a circular valve which stroke is limited by a crew nut. Under the collar there is a pocket which is connected hydraulically to annular channel between the collar and screw nut with axial channel of the housing. Outer diameter of the seal tightening is equal to inner diameter of the seal. The hollow step-type rod has thrust which comes in contact with mounting seat in the narrowing spot.

EFFECT: providing formation of hydraulic connection of annular space with tube side and maintenance of seal integrity.

2 dwg