Cut-off valve, also known as cut-off valve, is a mandatory sealed valve, so the valve is closed, the pressure must be applied to the valve to force the sealing surface does not leak. When the medium from the bottom of the valve into the valve, the operating force to overcome the resistance is the stem and packing friction and pressure generated by the medium thrust, off the valve force than the valve, so the stem Of the diameter to be large, otherwise there will be stem stem bending failure.Globe Valve
According to the connection is divided into three kinds: flange connection, threaded connection, welding connection. From the self-sealing valve appears, the valve flow of the valve will be changed from the top of the valve into the valve chamber, then under the action of the medium pressure, the valve is small, and open the valve force, stem diameter can be corresponding To reduce.Globe Valve
At the same time, in the role of the media, this form of the valve is more stringent. China's valve "three to" has been provided, the flow of the valve, all from top to bottom. When the valve is opened, the opening height of the valve is 25% ~ 30% of the nominal diameter, and the flow has reached the maximum, indicating that the valve has reached the full position. So the fully closed position of the cut-off valve should be determined by the stroke of the valve.
The opening and closing of the shut-off valve is a plug-shaped valve with a flat or sea conical surface, and the valve flap linearly along the centerline of the valve seat. The movement of the valve stem, as well as the lifting of the rotary rod type can be used to control the air, water, steam, corrosive media, mud, oil, liquid metal and radioactive media and other types of fluid flow.Globe Valve
Therefore, this type of shut-off valve is very suitable for cutting or adjustment and throttling. As the valve stem of the valve opening or closing stroke is relatively short, and has a very reliable cutting function, and because the valve seat changes and the valve seat stroke is proportional to the relationship between the very suitable for the flow of regulation.