ALL-PURPOSE VALVE FOR DOWNHOLE MOTOR Russian patent published in 2007 - IPC E21B4/02 

FIELD: drilling equipment, particularly bypass and check valves for downhole motors.

SUBSTANCE: valve comprises hollow body, shell and piston with bypass orifices, slider, spring and sealing means carried by piston, slider and shell, as well as shock absorber and head. The piston has support. The head has plate-like ledge. Shock absorber and head are joined with piston arranged in hollow body and shell. Slide is provided with seat and joined with hollow body and head having radial through channels. Shock absorber cooperates with spring arranged between shock absorber and slider and adjoins shell and piston stop. Slider seat rests upon plate-like head ledge.

EFFECT: possibility to combine by-pass valve and check valve in single assembly, increased operational reliability and safety, possibility to perform all types of technological operations associated with drill string trips, well drilling in difficult geotechnical conditions under all possible pressure drops in well bore and inside drill string.

1 dwg