Advantages and Disadvantages of Soft Sealing Gate Valves

Overview of soft sealing gate valves
A soft sealing gate valve is a manual valve used to connect media in water conservancy projects. A soft seal gate valve is composed of valve seats, valve bonnets, wedges, glands, valve stems, handwheels, gaskets, and hexagon socket bolts. The internal and external surface of the valve is all sprayed with electrostatic powder and then baked by a high-temperature furnace, which not only ensures the smoothness of the entire flow channel and internal wedge groove of the gate valve, but also showing a visual sense of color in appearance. The soft sealed gate valve is usually blue for general water conservancy, while the red coating will be coated for fire-fighting pipelines, which is deeply loved by users. It can even be said that the soft sealed gate valve is a valve made for water conservancy.
 
Types and uses of soft sealed gate valves
As a common manual valve on pipelines, soft sealed gate valves are mainly used in water plants, sewage pipelines, municipal drainage engineering, fire-fighting pipeline engineering, and slightly non-corrosive liquids and gases on industrial pipelines. They can be customized according to the situation of on-site use, such as soft sealed gate valves with rising stems, soft sealed gate valves with non-rising stems, soft sealed gate valves with extended stems, buried soft sealed gate valves, electric soft sealed gate valves, pneumatic soft sealed gate valves, etc.
 
What are the advantages of soft sealing gate valves?
1. First, the advantages of soft sealed gate valves are related to their costs. Generally, most of the soft sealed gate valve series adopt ductile iron QT450. The cost of the valve body made from ductile iron will be much more affordable than that of cast steel and stainless steel. This is quite economical compared to engineering batch procurement, and it is under the condition that the quality is also guaranteed.
 

2. Second, the advantages of soft sealed gate valves are related to the performance characteristics. The wedge of the soft sealed gate valve is lined with elastic rubber, and the inside is a wedge structure. The optional installation of the top handwheel mechanism allows the screw rod to drop to drive the elastic wedge to press down, and forms a seal with the inner wedge groove. Because the elastic rubber wedge can be stretched and squeezed to obtain a good sealing effect. Therefore, the sealing effect of soft sealing gate valves for water conservancy and some non-corrosive media is obvious.

 
3.Third, the advantages of soft sealed gate valves concerning the later maintenance. The structure of the soft sealed gate valve is simple and clear, and it is easy to disassemble and install. When the gate valve is used for a long time, the elastic wedge in the gate valve will lose its elasticity due to frequent opening and closing for a long time, resulting in the valve not being closed well and leakage of the valve. At this time, the advantages of the structural design of the soft sealed gate valve can be seen. The maintenance personnel can directly disassemble and replace the wedge without disassembling the entire valve, which saves time, effort, manpower and material resources on site.
 
What are the disadvantages of soft sealing gate valves?
Speaking of the shortcomings of soft sealed gate valves, they should be considered from an objective perspective. The core point of the soft sealed gate valve is that the soft sealed elastic wedge can extend, contract, and automatically compensate. The sealing and air-tightness of the soft sealed gate valve are really good for non-corrosive gases and liquids.
 
Of course, since nothing is perfect, there are advantages and disadvantages. The disadvantage of soft sealed gate valves is that the elastic rubber wedge cannot be used continuously at a temperature exceeding 80°C or conditions with hard particles and corrosiveness. Otherwise, deformation, damage, and corrosion will happen for elastic rubber wedge, resulting in leakage of pipelines. Therefore, the soft sealed gate valve is only suitable media without corrosion, particles, and wear.
 
Conclusion
You should know the characteristics, temperature, pressure, and on-site use of the medium when selecting the valve, combined with the advantages and disadvantages of the soft sealed gate valve described in the article for a comprehensive evaluation, and then choose it further. By doing that,  many details that are overlooked during selection can be avoided, and the valve can be used without worries.