Ball check valve to be used in the manhole pump system for sewage

摘要

PROBLEM TO BE SOLVED: To prevent biting-in of foreign matter such as small stone between a ball valve element and a guide in the body part by introducing such a structure that the ball valve element moves by its own weight certainly to a seat provided in the body part even in the case the foreign matter is positioned likely to be pinched by the ball valve element and guide. ;SOLUTION: A ball check valve is structured so that a body 1 having a inflow port 2 and outflow port 3 is provided with a seat 4 on the inflow side of the body 1 and a bal valve element 5 seated on the seat 4 is retreated to a retreat path 6 in the body part 1 through a guide 9, wherein the gap 35 between the apex 33 of the center line 32 of the valve element 5 crossing the fluid flow direction 31 when the valve element 5 is guided by the guide 9 and the guide inner surface 34 whereto the center line 32 confronts is made greater than the size of foreign matter 36 included in the fluid.;COPYRIGHT: (C)2001,JPO