Product Structure Of Stainless Steel Globe Valve

The opening and closing parts of the stop valve (Globe Valve) are plug-shaped discs, the sealing surface is flat or conical, and the disc moves in a straight line along the center line of the fluid. The movement form of the valve stem, (common name: dark rod), there is also a lifting and rotating rod type, (common name: open rod) globe valve is only suitable for full open and full closed, and is not allowed to be adjusted and throttled.

The globe valve is a forced seal valve, so when the valve is closed, pressure must be applied to the disc to force the sealing surface not to leak. When the medium enters the valve from the bottom of the valve disc, the resistance that needs to be overcome by the operating force is the friction between the valve stem and the packing material and the thrust generated by the pressure of the medium, and the force of closing the valve is greater than the force of opening the valve, so the diameter of the valve stem should be larger, otherwise the failure of the top bend of the valve stem will occur. In recent years, after the emergence of the self-sealing valve, the medium flow direction of the globe valve has been changed from the top of the valve disc into the valve cavity, at this time, under the action of medium pressure, the force of closing the valve is small, and the force of opening the valve is large, and the diameter of the valve stem can be reduced accordingly. At the same time, under the action of the medium, this form of valve is also tighter. China's valve "three to give" has stipulated that the flow direction of the globe valve is all top-down. This valve should be installed horizontally.

When the globe valve is opened, when the opening height of the valve disc is 25%~30% of the nominal diameter, the flow rate has reached the maximum, indicating that the valve has reached the fully open position. Therefore, the fully open position of the globe valve should be determined by the stroke of the disc.