STEAM TURBINE PROTECTION DEVICE Russian patent published in 2004 - IPC

FIELD: power engineering. SUBSTANCE: device is designed to protect steam turbine with mixing condenser. Proposed device contains stop valve and turbine technological parameters maximum deviation safeguards. Stop valve drive is connected through interpiston spaces along oil line in series with high-pressure oil source. Device is furnished with spring-loaded normally open vacuum popping valve connected through seat with plate to steam space of condenser and ambient atmosphere. Device is furnished with float-type condensate level relay in condenser with control spool valve and impulse spool valve. Interpiston space of control spool valve is connected first in direction of oil flow from high- pressure oil source to stop valve drive. Interpiston space is connected also to drive to vacuum popping valve. Interpiston space of control spool valve is connected through first interpiston space of impulse spool valve to high-pressure oil source and to oil tank. End face chamber is connected through second interpiston space of impulse spool valve and through interpiston space and end face chamber of said spool valve to oil tank. Spool of impulse spool valve is furnished with hydraulic damper. For this purpose bore is made in spool and cylindrical projection is made in housing of impulse spool valve to form ring groove getting into bore with radial clearance. Electromagnet switches off drive from turbine oil tank by electric signal and bypasses high-pressure oil delivery. Hydraulic damper slows movement of spool so that spool can return to its initial position without emergency oil pressure drop in oil line of turbine protection system. EFFECT: improved protection of steam turbine. 3 dwg