SHUT-OFF VALVE Russian patent published in 2003 - IPC

FIELD: oil and gas industry; shut-off fittings for oil fields, gas pipe lines, drain lines. SUBSTANCE: shut-off valve has body, gate, seat with elastic seal and worm drive of gate including worm and worm wheel with motion thread on inner surface. Gate is made in form of bush with motion thread on outer surface. Said thread on motion surface is engageable with motion thread of worm wheel. Body is provided with pin and bush is provided with slot which is engageable with slot. EFFECT: increased throughput flow capacity; enhanced tightness; reduced overall dimensions; reduced closing and opening force. 2 dwg