CHECK VALVE Russian patent published in 2002 - IPC

FIELD: pipe line fittings; piping systems handling water, petroleum products and other liquids. SUBSTANCE: check valve has body in form of sealed branch pipe with convex wall, flexible shut-off member and seat. Hollow seat is blanked off at one end. Side walls of seat are provided with ports. On side of liquid outlet, flow-forming cone is provided whose base is engageable with front walls of ports. Outer surface of cylinder on side of liquid inlet is circular shaped groove. Flexible shut-off member is made in form of bush which has thickened section on side of outlet. On opposite side, bush has thinned section with self-sealing edge and circular shaped projection located on its inner surface in circular shaped groove of seat. Thickened section of bush is divided by longitudinal grooves into trapezoidal sections whose large bases are directed towards seat and are provided with reinforcement on side of seat. Seat port axes are located at acute angle in way of motion of liquid towards body axis. Flow-forming cone is made in form of inert. EFFECT: enhanced operational reliability; reduced losses of pressure in passing through check valve. 2 dwg