Under what operating conditions should a globe valve be used?

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　　The globe valve is one of the most widely used valves. It is popular because it experiences low friction between its sealing surfaces during opening and closing, is durable, requires little clearance for full opening, is easy to manufacture, and convenient to maintain. It is suitable not only for medium and low pressures but also for high pressures. The closing principle of a globe valve is to rely on the pressure from the valve stem to bring the sealing surface of the valve disc into close contact with the sealing surface of the valve seat, thereby preventing the flow of the medium. It can be used to control the flow of various types of fluids, including air, water, steam, various corrosive media, mud, oils, liquid metals, and radioactive materials. Therefore, this type of isolation globe valve is very suitable for cutting off, regulating, and throttling. Due to the relatively short opening and closing stroke of the valve stem in this type of valve, as well as its highly reliable shut-off function, and because the change in the valve seat orifice is proportional to the stroke of the valve disc, it is highly suitable for regulating flow rate. 　　The axis of the stem of the stop valve is perpendicular to the sealing surface of the valve seat. The valve stem has a relatively short opening or closing stroke, and it provides a very reliable shut-off action, which makes this type of valve highly suitable for shutting off, regulating, or throttling fluids. 　　Once the disc of a globe valve is in the open position, there is no longer any contact between its seat and the sealing surface of the disc, resulting in a very reliable shut-off action; this makes such valves highly suitable for shutting off, regulating, or throttling fluids. 　　Once a globe valve is in the open position, there is no longer any contact between its seat and the sealing surface of the disc; as a result, mechanical wear on these sealing surfaces is minimal. Moreover, since the seat and disc of most globe valves are easy to repair or have their sealing elements replaced without the need to remove the entire valve from the pipeline, this makes them very suitable for situations where the valve is welded to the pipeline. The flow direction of the medium changes as it passes through such valves; therefore, the flow resistance of globe valves is higher than that of other valves. The commonly used globe valves include the following types: 1. Angle globe valve ； In angular stop valves, the fluid only needs to change direction once, resulting in a lower pressure drop across the valve compared to stop valves with conventional designs. 2. DC stop valve ； In straight-through or Y-type globe valves, the flow channel of the valve body forms an angle with the main flow path; as a result, the degree of disruption to the flow pattern is less than that in conventional globe valves, and consequently the pressure loss across the valve is also lower. 3. Plunger-type globe valve: This type of globe valve is a variant of the conventional globe valve. In such valves, the valve disc and seat are typically designed based on the plunger principle. The valve disc is polished to form a plunger that connects with the valve stem, and sealing is achieved through two elastic sealing rings fitted over the plunger. The two elastic sealing rings are separated by a collar, and the sealing rings around the plunger are pressed firmly in place by the load applied to the valve cover by the valve cover nut. The elastic sealing ring can be replaced and is made from a variety of materials. This valve is primarily used for opening or closing, but it also comes with special types of plungers or rings that allow for flow regulation.