1. Overview of globe valve

Globe valves, also known as shut-off valves, work on their unique opening and closing characteristics. During the opening or closing process, the friction between its sealing surfaces is relatively small, ensuring its durability. In addition, the height required for its opening is not large, the manufacturing process is relatively simple, and maintenance is also quite convenient. This makes the globe valve not only suitable for medium and low pressure environments, but also capable of stable operation in high pressure environments. The opening and closing components of the globe valve are plug shaped with a flat or conical sealing surface. When the valve disc moves in a straight line along the centerline of the fluid, the valve can be opened or closed. The closing principle lies in the pressure exerted by the valve stem, which causes the sealing surface of the valve disc to tightly adhere to the sealing surface of the valve seat, effectively preventing the flow of the medium. It is worth noting that globe valves have directionality and usually only allow one-way flow of the medium. Despite its relatively long structural length and high fluid resistance, it is precisely these characteristics that enable the globe valve to maintain high sealing reliability during long-term operation.

When installing a shut-off valve, special attention should be paid to the directionality of the fluid. Choosing the appropriate valve type is crucial for ensuring long-term sealing reliability. Due to the directional nature of the globe valve, it is necessary to ensure that the direction of its medium flow meets the design requirements during installation to ensure its reliability and efficiency.

2. Types and characteristics of globe valves

◆ Straight through globe valve

The characteristic of a straight through globe valve is that its medium inlet and outlet channels are designed in the same direction, forming a 180 ° angle. This design minimizes the degree of disruption to the flow state of the fluid when passing through the valve, effectively reducing the loss of fluid pressure caused by the valve. The straight through design reduces fluid pressure loss and is suitable for general fluids.

◆ DC globe valve

The design of the DC globe valve is unique, with a certain angle between the valve stem and the channel, and a certain inclination angle between the valve seat sealing surface and the inlet and outlet channels. This clever design allows the fluid to pass through the valve almost without changing its original flow direction, greatly reducing the resistance of the fluid in the shut-off valve. Therefore, DC globe valves have the smallest flow resistance characteristics among various globe valves. Especially suitable for conveying pipeline systems containing coking and solid particles. Medium with low flow resistance, suitable for coking and solid particles.

◆ Angle type globe valve

The design feature of the angle type globe valve lies in the 90 ° angle between its medium inlet and outlet channels. Although this design may generate a certain pressure drop, it brings significant convenience. Suitable for installation at pipeline bends, saving bends and facilitating operation.

3. Valve stem type

The design of the threaded stem globe valve is unique, with the stem thread located on the outside of the housing, completely isolated from the working medium, and therefore not affected by medium corrosion. In addition, this design also facilitates lubrication, making the operation process more effortless. The characteristic of a down threaded stem globe valve is that its stem thread is located inside the valve body, in direct contact with the working medium. However, this design makes the valve stem threads susceptible to corrosion by the medium and difficult to lubricate. Therefore, this type of globe valve is usually suitable for situations where the nominal diameter is small and the working temperature of the medium is not high. Divided into upper thread and lower thread, each with its own applicable scenarios.

4. National standard globe valves and other types

◆ National standard globe valve

The national standard globe valve occupies an important position in the globe valve series and is one of the most widely used products. The sealing surfaces of the valve disc and valve seat have undergone special processing, using different hardness Stellite cobalt based hard alloys for welding, ensuring reliable sealing performance. In addition, the valve also has excellent wear resistance, high temperature resistance, corrosion resistance, and abrasion resistance, and is widely used in occasions that require wear resistance, high temperature resistance, and corrosion resistance.

◆ Fluorine lined globe valve

Fluorine lined globe valve, also known as fluoroplastic lined corrosion-resistant valve, is a key technology that cleverly places polytetrafluoroethylene resin (or profile) on the inner wall of steel or iron valve pressure parts and the outer surface of valve internals through molding (or embedding) process. This unique manufacturing process enables the valve to demonstrate excellent performance in resisting strong corrosive media, and is suitable for pipeline systems with various strong acids, strong bases, organic solvents, corrosive gases, and liquid media. The working temperature ranges from -50 to 150 ℃.

Needle valve and low-temperature shut-off valve

Needle valves, with their small diameter design, play a crucial role in instrument measurement pipeline systems. It can not only achieve precise opening and closing functions, but also finely control the flow rate. This type of valve is widely used in various fields, such as power station instruments, oilfield specialized equipment, and American standard series, providing reliable guarantee for instrument measurement. Used for instrument systems that require precise flow control. Low temperature globe valve, designed for environments with working temperatures below -110 ℃, is a key equipment in liquefied natural gas, liquefied petroleum gas, and other low-temperature industries.

◆ Piston type and other types

The unique feature of plunger globe valve, also known as plunger globe valve, lies in the design of its sealing surface. This design adopts a radial sealing structure, which tightly compresses the elastic sealing ring around the plunger by using two elastic sealing rings fitted on the polished plunger and the load applied by the connecting bolts between the valve body and the valve cover, thereby achieving reliable shut-off sealing. The plunger valve design provides reliable sealing and is suitable for industrial and mining environments.