GAS-LIFT PILOT VALVE Russian patent published in 1994 - IPC

FIELD: gas and oil producing industry. SUBSTANCE: gas-lift pilot valve includes body 1 with upper control channel a and lower control channel d, inlet channels b and outlet channels c. Installed in body square to its axis is eat 13 with through channel 14 hydraulically connected by means of transverse channels with body lower control channels d. Installed above seat 13 is rod 9 with drive in upper part and gate 10 on lower end. Located under seat is flexible locking member 15 in form of sleeve. Thrust bearing is disposed under flexible locking member. Installed inside locking member is retainer 17 with channels 18. Retainer is made in form of stepped fork, and thrust bearing is made in form of branch pipe whose axial channel 5 is hydraulically communicated with space beyond body. Sum of cross-section areas of branch pipe axial channel 5 and body outlet channels c is less than that of inlet channels, and cross-section area of lower control channels d is less than that of seat through channel. Flexible locking member has annular corrugation under retainer and stiffening ribs 16 on its inner surface. Valve also has removable retainer 11 of rod upper position. EFFECT: higher efficiency. 2 cl, 2 dwg