VALVE FOR WELL DEVELOPMENT Russian patent published in 2014 - IPC E21B34/06 F16K15/06 

FIELD: oil-and-gas industry.

SUBSTANCE: valve comprises hollow body with coupling and union threaded ends for coupling with flow string and with radial hole, hollow slide valve with radial bore and piston. Hollow slide valve is arranged off centre relative to said body and rigidly fixed at its outer surface. Radial bores of the body and slide valve are intercommunicated, hollow slide valve being provided with lateral channel. Piston is rigidly secured at rod lower part while rod upper part is provided with outer circular ledge and fitted tightly in adjusting nut for axial displacement relative to adjusting nut. Adjusting nut is screwed in hollow slide inner thread made at its top end. The piston is spring loaded downward from said nut. Fluid chamber communicated with the body inner space is made in said slide valve. Overpressure in said fluid chamber makes piston displace axially upward to communicate said chamber with the well casing annulus via the slide valve lateral channel.

EFFECT: decreased and controlled hydraulic pressure, ease of logging instrument arrangement, combination of several jobs in one lowering of tubing.

1 dwg