CHANGE-OVER DEVICE OF SAFETY VALVE UNIT Russian patent published in 1999 - IPC

FIELD: transportation of gas; gas distributing stations, compressor stations and other objects of gas pipe line transport. SUBSTANCE: device has body with inlet passage and two outlet passages having coaxial seats. Double-acting gate is fitted coaxially between seats; rod of this gate is kinematically linked with drive. Each outlet passage is connected with inlet of safety valve. Gate is made in form of spring-loaded intake valves and double-acting valve which are located concentrically relative to rod and are engageable with each other and with rod in preset sequence by means of stop rigidly linked with rod. Effective area of intake valves is lesser than effective area of double-acting valve; double-acting valve and seats engageable with it are cone-shaped in form. EFFECT: extended field of application; enhanced operational reliability. 2 dwg