What's the difference between a stop valve and a check valve? Is it a valve?
A check valve is a valve that automatically prevents the flow of fluid. The disc of the check valve is opened under the action of fluid pressure, and the fluid flows from the inlet side to the outlet side. When the inlet side pressure is lower than the exit side, the valve automatically closes under the influence of fluid pressure, gravity and other factors to prevent fluid flow backwards. The function of this type of valve is to allow the medium to flow in one direction and to prevent flow in the direction. Usually the valve is automatically work, fluid pressure flow in one direction, the valve open; the opposite direction of fluid flow by gravity, fluid pressure and valve closing effect on the valve seat, thereby cutting off flow. Among them, the check valve belongs to this type of valve, which includes swing check valve and lift check valve. The swing check valve has a hinge mechanism and a gate like valve free against the inclined seat surface.
The cut-off valve has the following advantages: 1. in the process of opening and closing, the friction of the sealing surface is smaller than that of the gate valve, and it is wearable. 2. high opening height. 3. usually only a sealing surface, the manufacturing process is good, easy to repair. The valve is widely used, but because the opening and closing torque is large, the structure length is longer, usually the nominal diameter of DN are limited to the following 200mm. The flow resistance of the stop valve is greater. Thus limiting the wider use of cut-off valves.
The cut-off valve is a common valves, mainly used to connect or disconnect the line of medium, generally not for regulating flows.globe valves for a wide range of pressure and temperature, but are generally used for medium and small diameter pipes. The cut-off valve is closed parts (valve) moving along the centerline of the valve seat valve. The stop valve is mainly used for cutting in the pipeline.
