Maintenance Procedures:
Pre-use cleaning
Flush pipelines and the valve's flow passage with water before operation to remove residual metal shavings or debris.
Pressure release during maintenance
When closed, the valve retains residual media under pressure. Before maintenance:
Close the upstream shutoff valve
Open the ball valve fully to release internal pressure
Disconnect power and air supply for electric/pneumatic valves.
Seal protection during cleaning
Soft-sealed valves use PTFE seals; hard-sealed valves feature welded metal surfaces
Exercise extreme caution when disassembling to avoid damaging seals.
Flange bolt tightening sequence
Tighten flange bolts uniformly in a cross pattern. Sequential tightening causes uneven force distribution, damaging gaskets and causing leaks.
Cleaning solvent selection
| Valve Type | Solvent | Notes |
|---|---|---|
| Gas valves | Gasoline | Avoid corrosive chemicals |
| General valves | Water/Alcohol | Ensure complete solvent evaporation before reassembly |
Minor stem seal leakage
Slightly tighten the stem nut until leakage stops. Do not overtighten.
Storage requirements
Prevent rust by storing indoors with flange protectors installed
Avoid rain, moisture, and humidity
Re-test valves stored >12 months before use.
Key Technical Nuances:
Seal preservation: Abrasive media accelerates PTFE seal wear; hard-sealed variants suit particle-laden flows.
Actuator maintenance: Regularly lubricate pneumatic cylinders (ISO VG68 grease recommended).
Performance verification: Post-storage testing must include seat leakage checks per API 598 standards