GATE VALVE Russian patent published in 1999 - IPC

FIELD: shut-off fittings; shutting-off flows of working medium in main pipe lines. SUBSTANCE: gate valve includes body, shut-off disks and spring-loaded stem. Stem is connected with wedge which is linked with shut-off disks by means of solids of revolution. Cover is connected with body by means of fastening members and is sealed up by first ring which is locked with other rings. Last ring is received by bore of body. Second ring is positioned between outer surface of cover and first ring. Cover is provided with two lugs. Fastening members are connected with above-mentioned lugs by means of thread. They rest against end surface of body. Lugs are located vertically at distance not lesser than thickness of any of above-mentioned rings. According to second versions, gate wedge is movably connected with stem. Spring used for loading the stem is plate-type in construction. EFFECT: effective operation of gate valve at high pressure in main due to modified construction of sealing unit and relief of drive. 8 cl, 5 dwg