VALVE Russian patent published in 1998 - IPC

FIELD: manufacture of fittings for opening and closing pipe lines of large diameters for transportation of liquid media. SUBSTANCE: valve includes body 1 with straight-way flow section having inlet and outlet holes 3 and 4 and seat 5; central body 7 mounted in flow section on pylons with cylindrical working chamber 8 where piston 9 is located, shut-off member 10 secured on piston on side opposite to working chamber, valve opening passage 11 and valve closing passage 12; communicating passage 13 brought in communication with working chamber and distributing device for alternate communication of communicating passage with valve opening and closing passages. Seat 5 is located after central body 7 in way of flow and after shut-off member 10 before outlet hole 4; opening passage 11 is brought in communication with flow section in way of flow of medium after seat 5 and closing passage 2 is connected to flow section in way of flow of medium before seat 5. Communicating passage 13 is provided with differential throttle valve 17 with different coefficients of hydraulic resistance (depending on direction of motion) which is made in form of flow-through body with projections of different height and is mounted in body for axial displacement of piston. In zone of connection of closing passage 12 flow section is provided with local widening 24; shut-off member 10 has one or several projections 25 located in flow section. EFFECT: enhanced reliability. 4 cl, 3 dwg