What's the difference between the cut-off check valve and the stop valve?
The principle difference between the check valve and the cut-off valve is that the non-return valve allows only one-way flow of liquid, allowing only one flow from one end to the other. It is a one-way valve, and the shut-off valve allows two-way flow. The biggest difference is the structure of the valve head and valve closing method is connected by the check valve is separated, the appearance of the cut-off valve import and export in a plane and the cut-off valve is a one-way valve, arrow shell stop check valve on the other.
Purely from the outward appearance is indistinguishable, but if you do not open the valve body, it can still be differentiated. Turn off the check valve and stop valve (turn the handwheel to the open, the valve stem up), and then shake the two valve, which is relatively large movement, then this is the cut-off check valve.
The stop check valve prevents backflow and is indistinguishable from the exterior, but can be separated from the spool.
