Valve seal ring common materials and service conditions Valve manual gas gate valve

Valve seal ring common materials and service conditions Valve manual gas gate valve

Valve sealing ring materials have metal and non-metal two categories. Common materials and their conditions of use are as follows:
1. Synthetic rubber
Synthetic rubber is better than natural rubber in oil resistance, temperature resistance and corrosion resistance. General synthetic rubber temperature t ≤ 150℃, natural rubber t ≤ 60℃, rubber used for nominal pressure PN ≤ 1MPa globe valve, gate valve, diaphragm valve, butterfly valve, check valve, clamp valve and other valves seal.
2, nylon
Nylon has the characteristics of low friction coefficient and good corrosion resistance. Nylon is mainly used for temperature t ≤ 90℃, nominal pressure PN ≤ 32MPa ball valve, globe valve.
3. Teflon
Ptfe is mainly used in globe valves, gate valves and ball valves with temperature T ≤ 232℃ and nominal pressure PN ≤ 6.4MPa.
4, cast iron
Cast iron is used for gate valves, globe valves and plug valves for gas and oil, with temperature T ≤ 100℃ and nominal pressure PN ≤ 1.6mpa.
5. Babbitt alloy
Babbitt alloy is used for ammonia stop valves with temperature T-70 ~150℃ and nominal pressure PN ≤ 2.5MPa.
6. Copper alloy
Common materials of copper alloy are 6-6-3 tin bronze and 58-2-2 manganese brass. Copper alloy wear resistance, suitable for temperature T ≤ 200℃, nominal pressure PN ≤ 1.6MPa water and steam, often used in gate valves, globe valves, check valves, plug valves, etc.
7, chrome stainless steel
Chrome stainless steel commonly used brands are 2Cr13, 3Cr13 after quenching and tempering treatment, good corrosion resistance. Often used for temperature t ≤ 450℃, nominal pressure PN ≤ 32MPa water, steam and oil and other media valves.
8, chromium nickel titanium stainless steel
The commonly used brand of chromium nickel stainless steel is 1Cr18Ni9ti, which has good corrosion resistance, erosion resistance and heat resistance. Suitable for temperature T ≤ 600℃, nominal pressure PN ≤ 6.4MPa steam, nitric acid and other media, used for globe valve, ball valve, etc.
9, nitriding steel
The common grade of nitriding steel is 38CrMoAlA, which has good corrosion resistance and abrasion resistance after carburizing. It is usually used for power station gate valves with temperature T ≤ 540℃ and nominal pressure PN ≤ 10MPa.
10, boronizing
Boronizing by the body or disc body material directly processed sealing surface, boronizing surface treatment, sealing surface wear resistance is very good. Used for power plant blowdown valve.
Gas gate valve Manual valve Manually turn the handwheel by hand to make the stem rise and fall, so as to drive the gate plate up and down to open and close the valve. The VALVE IS EQUIPPED WITH “OPEN” AND “CLOSE” INDICATING MECHANISM, ROTATE CLOCKWISE, THE GATE FALLS, THE pointer POINTS TO THE “CLOSE” POSITION, and THE VALVE IS CLOSED. Turn COUNTERCLOCKWISE, THE GATE RISES, THE NEEDLE points TO THE “ON” POSITION, AND THE VALVE OPENS. When testing the pressure of the pipeline, it is necessary to use the extended rod handwheel. Close valve and must close in place (observe pointer position). Turn the handwheel clockwise to close, and turn it counterclockwise to open.
Range of 1.
Manual operated gas gate valves with nominal diameter DN100mm~300mm and nominal pressure PN0.8mpa flanged end connection are included in this specification.
2. Use
2.1 This valve is used as the opening and closing device on the town gas and natural gas pipelines.
2.2 Select the material of the valve according to the medium.
2.2.1 Ductile iron valve is suitable for gas, natural gas and other media.
2.3 Applicable temperature:
2.3.1 The applicable temperature of ductile iron valve is ≤120℃
Structure of 3.
3.1 Basic structure of gas gate valve is shown in Figure 1
3.2 The gasket of wearing parts is filled with rubber asbestos board and fluorine rubber to ensure reliable sealing.
4. Operating
Manual VALVES TURN THE HANDWHEEL BY HAND TO RAISE AND LOWER THE STEM, thus DRIVING THE GATE UP AND down TO OPEN AND CLOSE THE VALVE. The VALVE IS EQUIPPED WITH “OPEN” AND “CLOSE” INDICATING MECHANISM, ROTATE CLOCKWISE, THE GATE FALLS, THE pointer POINTS TO THE “CLOSE” POSITION, and THE VALVE IS CLOSED. Turn COUNTERCLOCKWISE, THE GATE RISES, THE NEEDLE points TO THE “ON” POSITION, AND THE VALVE OPENS.
5. Storage, maintenance, installation and use
5.1 The valve shall be stored in a dry and ventilated room, and both ends of the valve passage shall be blocked.
5.2 Long-term stored valves should be regularly inspected for dirt. Special attention should be paid to the cleaning of the sealing surface to prevent the damage of the sealing surface.
5.3 Before installation, carefully check whether the valve mark is in accordance with the use requirements.
5.4 Before installation, the inner chamber and sealing surface of the valve should be checked. If there is dirt, it should be cleaned with a cleaning cloth.
5.5 Pipes must be cleaned before and after installation to ensure that there is no residue in the pipes
5.6 When testing the pressure of the pipeline, the extended rod handwheel must be used. Close valve and must close in place (observe pointer position). Turn the handwheel clockwise to close, and turn it counterclockwise to open.
5.7 The valve should be blown regularly to prevent coking.
5.8 The valve should be lubricated regularly (10~15 days) to lubricate the sealing pair and the valve stem and other moving pairs to reduce the switching torque and protect the sealing pair.
6. Possible faults, causes, and troubleshooting methods are listed in the table
Table 1 Possible faults, causes, and troubleshooting methods 1
The warranty of 7.
The manufacturer is responsible for the warranty of the valve within one year after it is put into use, but not more than 18 months after delivery. During the warranty period, due to product quality reasons can be repaired or replaced.
8. Ordering instructions
Please state when ordering
Nominal pressure MPa
Nominal diameter mm
Structure length standard
Flange connection size standard
With non-oiling device
Handwheel device and dimensions with or without extension rod