Globe Valves

Globe valve

Globe valve, also known as shut-off valve, belongs to the forced sealing valve, so when the valve is closed, pressure must be applied to the valve flap to force the sealing surface not to leak. When the medium enters the valve from below the valve flap, the resistance that the operating force needs to overcome is the friction of the stem and packing with the thrust generated by the pressure of the medium, the force of closing the valve is larger than the force of opening the valve, so the diameter of the stem should be large, otherwise the failure of the stem top bend will occur. According to the connection method is divided into three kinds: flange connection, fillet connection, welding connection. From the emergence of self-sealing valves, the media flow direction of the globe valve is changed from above the valve flap into the valve cavity, then under the action of media pressure, the force to close the valve is small, while the force to open the valve is large, 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 has stipulated that the flow direction of the shut-off valve, all use top-down. When the shut-off valve is opened, the opening height of the valve flap, 25% to 30% of the nominal diameter. Flow has reached the maximum, that the valve has reached the full open position. Therefore, the fully open position of the stop valve should be determined by the stroke of the valve flap.

Stop valve (stop valve, Globe Valve) of the opening and closing parts is a plug-shaped valve, sealing above the plane or sea cone surface, the valve flap along the center line of the valve seat for linear motion. The movement of the valve stem form, (common name: concealed rod), there are also lifting and rotating rod type can be used to control the flow of various types of fluids such as air, water, steam, various corrosive media, slurry, oil, liquid metal and radioactive media. Therefore, this type of interceptor shut-off valve valve is ideal for cut-off or regulation as well as throttling. Because the stem opening or closing stroke of this type of valve is relatively short, and has a very reliable cut-off function, and because the change of the valve seat opening is proportional to the stroke of the valve flap, it is very suitable for the regulation of flow.

Flange type globe valve

Threaded globe valve

Welded globe valve