วาล์วประตูมีด, หรือที่เรียกว่าวาล์วประตูมีด, เป็นวาล์วชนิดทั่วไป. เนื่องจากข้อดีของโครงสร้างที่เรียบง่าย, ขนาดเล็ก, และติดตั้งง่าย, it has been widely used in various industrial applications. Let’s introduce its main functions below.
Application of knife gate valve
1. Fluid cutting: Knife gate valve has excellent cutting performance and can quickly and reliably cut off fluid flow. They are widely used in situations where fluid flow needs to be cut off urgently or maintenance work is carried out.
2. Flow regulation: Knife gate valves can be used to regulate the flow of fluids, although their regulation capabilities are relatively limited. It is typically used in applications with lower requirements for fluid flow regulation, such as basic flow control in fluid piping systems.
3. Prevent reverse flow: Knife gate valves usually have good sealing performance and can effectively prevent reverse flow of fluid. This is important in applications where fluid backflow needs to be prevented or equipment protected.
4. Safety equipment: The knife gate valve can be used as an emergency shut-off device to ensure that the fluid flow is quickly cut off in the event of an accident or emergency to protect the safety of personnel and equipment.
5. Pressure control: Knife gate valves can be used to control the pressure in the system. By adjusting the opening of the valve, the pressure of the fluid can be changed to meet specific process requirements.
6. Discharge function: Knife gate valve can be used to discharge waste liquid or waste gas in the pipeline. Open the knife gate valve to drain the fluid from the pipe.
ในระยะสั้น, the main uses of knife gate valves include cutting off pipeline fluid, throttling control, medium regulation, backflow prevention and pipeline cleaning, ฯลฯ. It is widely used in pipeline systems in various fields such as the อุตสาหกรรมปิโตรเคมี, โลหะวิทยา, พลังงานไฟฟ้า, การก่อสร้าง, ฯลฯ. In the mining and steel industries, knife gate valves are used to handle media such as coal and filter slurries. In purification devices, it can be used to treat wastewater, สารละลาย, sewage and clarified water with suspended solids. In the papermaking industry, knife gate valves can be applied to pulp and feed-water mixtures of any concentration. It can be used to treat ash slurry during ash removal in power stations.
Knife gate valve selection
Regarding the selection of the main material, process and structure of the knife gate valve, the main material needs to be selected according to the physical and chemical properties of the medium. Optional materials include WCB, ซีเอฟ8, CF8M, CF3, CF3M and duplex steel 2205. When selecting the process of valve trim, the temperature of the medium should be considered. The processing technology of the gate can be selected from 20Cr13+Cr (ซีลอ่อน, hard seal), 304+Cr (ซีลอ่อน), 316+Cr (ซีลอ่อน) or 2205+Cr (hard seal). The treatment process of the valve seat can be selected from 304 (316) + stl, PTFE or EPDM. Depending on the characteristics of the medium, different types of knife gate valves can be selected. For example, ordinary knife gate valves are suitable for switching solid particles, fibers, and suspended media, and penetrating gate valves are suitable for switching and slag discharge systems for media that are prone to jamming. The square knife gate valve is more suitable for slag discharge systems, while the double knife gate valve is suitable for systems that require fast opening and closing and do not have strict sealing requirements.
1. For water media, general soft-sealed knife gate valves can be used. If the water contains trace particles but the sealing requirements are not high, you can choose the body hard seal; if the sealing requirements are high, you can choose polytetrafluoroethylene or polyurethane.
2. For cement mixtures, a square gate valve can be selected for dry materials at the discharge port. For wet and dry pipeline materials, if the sealing requirements are not high, you can use the body hard seal; if the sealing requirements are high, you can choose PTFE or polyurethane.
3. For plastic particles, generally choose body hard seal and 201 valve plate. If safety is considered, nitriding treatment can be performed, but the sealing performance after treatment is worse than that of hard sealing.
4. For coal, if you consider the corrosion of sulfur, you can choose the SS304 body hard seal; if you do not consider the corrosion, conventional hard-seal knife gate valves can be used. The sealing material of coal slurry should be polyurethane.
ในที่สุด, working with a strong and reputable valve manufacturer will help you choose the most suitable knife gate valve to ensure the smooth operation of your industrial project or system. Farpro Yuanda Industrial Valve Manufacturer is a partner you can’t miss, feel free to contact us at any time.