STEAM-TURBINE FAST-CLOSING GATE Russian patent published in 2002 - IPC

FIELD: thermal engineering; steam turbines. SUBSTANCE: gate has body, seat, actuator shaft, driven lever, and disk suspended within body from driven lever on actuator shaft. Disk is provided with seat of pressure-relief valve. Gate is also provided with driving lever fitted onto actuator shaft and also with hydraulic actuator incorporating controller with two servomotors; servomotors have spring-loaded differential bushings and disk valves whose rods are arranged unidirectionally and connected to actuator shaft to form annular cavities in actuator and working chambers of servomotors intercommunicating through ducts. Gate seat surface engageable with disk is inclined to center line of seat. Levers have slot and boss forming in assembly grip with two stops and clearance in-between. Controller is provided with movable box joined with one of actuator servomotors. Mounted in box bore are spring and shut-off valve with two spaces between pistons; shut-off valve contacts control gear rod of controller; to this end chamber of non-spring-loaded end of shut-off valve in box communicates with oil line of turbine protective gear. Working chambers of servomotors are connected through first space between pistons of shutoff valve to oil lines running to turbine protective system and to oil tank drain; annular cavities of servomotors communicate through second space between pistons of shut-off valve with high-pressure oil line and turbine protective system oil line. Proposed gate functions as stop valve and its actuator builds up net torque. EFFECT: enhanced reliability. 2 cl, 3 dwg