CHECK VALVE Russian patent published in 2012 - IPC F16K15/04 E21B34/06 

FIELD: oil and gas industry.

SUBSTANCE: check valve has housing 1 with installed on it shutoff member in the shape of a ball 8. Ball 8 is installed in stepped shell 7 with axial through channel. Shell 7 is provided with upper trap of ball 9 and seat 10. Seat 10 is located in site of coupling of axial channel parts with cross-sections different from each other. Shell has radial through holes 11 in upper part of side wall. Spring 3 is installed inside valve. Spring 3 is located on lower limit stop 2 installed in housing 1 with possibility of axial movement. Valve has additional shutoff member in the form of the second ball 13. Ball 13 is installed in sleeve 12 with axial channel of variable cross-section and seat 14. Seat 14 is located in upper part of sleeve 12 in site of coupling of axial channel parts with cross-sections different from each other. In side walls of sleeve there are through holes 15 made. Stock 16 is installed in axial channel of sleeve 12. Stock 16 interacts with ball 13 and is sprung by spring 3. Flow splitter in the form of bushing 4 is installed in housing 1. Shell 7 is fixed on upper end of bushing 4, sleeve 12 is fixed on lower end of bushing 4. There are at least two channels 5 of forward flow and at least two channels 6 of backward flow inside bushing 4.

EFFECT: increasing reliability of valve operation due to improving of its tightness.

2 cl, 4 dwg