Most forged steel valves use flange connections,
According to the shape of the connecting surface, it can be divided into the following types:
1. Lubrication type: used for forged steel valves with low pressure. Processing is relatively convenient
2. Concave convex type: With high homework pressure, medium hard gaskets can be used
3. Mortise and tenon type: It can use gaskets with large plastic deformation, which are widely used in corrosive media and have good sealing effect.
4. Trapezoidal groove type: using elliptical metal rings as gaskets, used for valves with operating pressure ≥ 64 kg/cm2 or high-temperature valves.
5. Lens type: The gasket is in the shape of a lens and made of metal. Used for high-pressure valves or high-temperature valves with a working pressure of ≥ 100 kg/cm2.
6. O-ring type: This is a relatively new flange connection method that developed with the emergence of various rubber O-rings, and it is used in sealing effect connection.
The connection method and maintenance details of forged steel valves
Attention to details in the maintenance of forged steel valves:
1. Attention should be paid to the storage environment of forged steel valves, which should be stored indoors in dry and ventilated areas, and the two ends of the passage should be blocked.
2. Forged steel valves should be inspected regularly, and any dirt on them should be removed. They should also be coated with rust proof oil on their surface.
3. The forged steel valve after device application should be repaired regularly to ensure its normal operation.
4. The valve sealing surface should be checked for wear and repaired or replaced according to the condition.
5. Check the trapezoidal thread wear condition of the forged steel valve stem and stem nut, whether the packing is outdated or ineffective, and make necessary replacements.
6. Conduct experiments on the sealing performance of valves to ensure their performance.
7. The valve in operation should be intact, the bolts on the flange and bracket should be complete, the threads should be intact, and there should be no looseness.
8. If the handwheel is lost, it should be promptly equipped and cannot be replaced with an adjustable wrench.
9. The packing gland is not allowed to be skewed or have no pre tightening gap.
10. If the valve is used in a harsh environment and is susceptible to infection by dirt such as rain, snow, dust, and sandstorms, a protective cover for the valve stem device should be used.
11. The ruler on forged steel valves should be intact, accurate, and clear, and the lead seal and cap of the valve should be intact.
12. Doubts about dents and cracks in insulated forged steel valves.
13. During operation, forge steel valves and avoid hitting them or supporting heavy objects.
