National standard steam shut-off valve

Introduction to J41H-40C National Standard Steam Stop Valve
The national standard steam globe valve, also known as the shut-off valve, belongs to the forced sealing type valve. Therefore, when the valve is closed, pressure must be applied to the valve disc to force the sealing surface not to leak. When the medium enters the valve from below the valve disc, the resistance that the operating force needs to overcome is the frictional force between the valve stem and the packing, as well as the thrust generated by the pressure of the medium. The force required to close the valve is greater than the force required to open it, so the diameter of the valve stem should be larger, otherwise the valve stem bending fault may occur. There are three types of connections: flange connection, threaded connection, and welded connection. After the appearance of self sealing valves, the flow of the medium in the shut-off valve is changed to enter the valve chamber from above the valve disc. At this time, under the pressure of the medium, the force to close the valve is small, while the force to open the valve is large, and the diameter of the valve stem can be correspondingly reduced. Meanwhile, under the influence of the medium, this type of valve is also relatively tight.

Performance of J41H-40C National Standard Steam Stop Valve

Valves play an important role in cutting off and throttling the medium in the pipeline they are located in. As an extremely important cut-off valve, globe valves seal by applying torque to the valve stem, which exerts pressure on the valve disc in the axial direction, making the sealing surface of the valve disc tightly fit the sealing surface of the valve seat, preventing the medium from leaking along the gaps between the sealing surfaces.

The sealing pair of the globe valve consists of the sealing surface of the valve disc and the sealing surface of the valve seat. The valve stem drives the valve disc to move vertically along the centerline of the valve seat. The opening height of the globe valve is relatively small during the opening and closing process, making it easy to adjust the flow rate, and easy to manufacture and maintain, with a wide range of pressure applications.

Compared with another commonly used shut-off valve in industrial production, the shut-off valve is structurally simpler and easier to manufacture and maintain. In terms of service life, the sealing surface of the globe valve is not easily worn or scratched. During the valve opening and closing process, there is no relative sliding between the valve disc and the sealing surface of the seat, so the wear and scratches on the sealing surface are relatively small, which improves the service life of the sealing pair. The globe valve has a small valve disc stroke and a relatively small valve height during the fully closed process. The disadvantage of globe valves is that they have a large opening and closing torque and are difficult to achieve rapid opening and closing. Due to the tortuous flow path inside the valve body, the fluid flow resistance is high, resulting in significant loss of fluid dynamics in the pipeline.