Product Instruction Manual
Name: Swing Check Valve
A swing check valve is a valve that automatically prevents fluid backflow. Its disc opens automatically under fluid pressure, allowing fluid to flow from the inlet side to the outlet side. When the pressure on the inlet side is lower than that on the outlet side, the disc closes automatically under the combined effect of fluid pressure difference and self-weight to prevent fluid reverse flow. It is widely used in piping systems for metallurgy, power stations, refineries and petrochemical plants.
1.Main Features
1.Simple structure and reliable operation. Its flow resistance is lower than that of lift check valves, suitable for large-bore applications.
2.It can open automatically by means of fluid pressure.
3.It is only applicable for unidirectional medium.
2.Technical Specifications
1.Nominal Pressure：1.6-75MPa
2.ominal Diameter：DN50-1000mm
Casting Materials：CF3m、CF3、CF8m、CF8、CF8c、WCB、20crmov、15cr1mov、WC6、WC9
Forging Materials：A105、20#、12cr1mov、F22、F91、304、316、316L
3.Applicable Standards
1.Design Standard：GB 12236-89
2.Inspection and Test Standard：JB/T 9092-1999
3.Face-to-Face Dimension：GB 12221-1989
4.Flange Connection Dimensions：JB79-1994
4.Material of Main Parts, Applicable Medium and Temperature
| Part Name |
Material |
|
Body, Bonnet, Disc, Lever, Bracket |
WB36 |
|
Bolt |
35CrMo |
|
Nut |
35CrMo |
|
Gasket |
Flexible Graphite + 304 |
|
Applicable Temperature |
-29~425℃ |
|
Applicable Medium |
Water, Steam, Oil Products, etc. |
5.Storage, Installation, Operation and Maintenance
1.Valves shall be stored indoors in a relatively dry environment.
2.For valves stored for a long time, regularly check whether the end protectors are intact, remove dust and dirt, and apply anti-rust oil on machined surfaces to prevent corrosion.
3.Before installation, verify the valve marking to confirm compliance with requirements, then remove the end protectors and thoroughly clean the valve.
4.When closed, the valve only needs to cut off the medium flow.
6.Possible Malfunctions and Troubleshooting
| Malfunction |
Cause |
Remedy |
|
Leakage at joint between valve body and bonnet |
1. Bolts not tightened or unevenly tightened2. Flange surface damaged or contaminated3. Gasket failure |
1. Re-tighten bolts evenly after system depressurization2. Repair sealing surface and remove contaminants3. Replace gasket |
|
Leakage at disc sealing surface |
1. Foreign matter trapped on sealing surface2. Damage to sealing surface |
1. Clean thoroughly2. Repair the damaged sealing surface |
|
Sticky operation of valve (not opening/closing smoothly) |
1. Worn, bent or deformed pin shaft |
1. Replace the pin shaft |
Safety Operation:
Loosen and adjust the connecting bolts between bonnet and valve body, as well as the connecting bolts of side flange and pipeline only after the system is depressurized.
