Troubleshooting Common Petrochemical Air Release Valve Issues

Solving Air Valve Issues in Petrochemical Systems

Valve Not Releasing Air Properly

Symptoms:

• Persistent air pockets in the pipeline
• No audible venting or release sounds
• Flow instability or surging

Possible Causes:

• Blocked or clogged orifice (due to salt, sediment, or scale)
• Float mechanism stuck or corroded
• Incorrect valve sizing or placement

Solutions:


• Remove and clean the orifice and internal chamber
• Inspect and free up or replace the float mechanism
• Confirm correct installation at the highest pipeline point
• Consider a self-cleaning or corrosion-resistant valve for severe environments

2. Continuous Water Leakage from the Outlet

Symptoms:

• Dripping or spraying water from valve vent
• Decreased line pressure or volume loss
• Water damage near installation area

Possible Causes:

• Worn or damaged seal
• Debris stuck in the seat
• Float not sealing fully due to wear or misalignment

Solutions:

• Shut off the line and disassemble the valve
• Inspect and clean seat and sealing surfaces
• Replace worn seals or float assemblies
• Review maintenance schedule for routine inspection

3. Valve Fails During Startup or Shutdown

Symptoms:

• No air release during filling
• Vacuum not broken during draining
• System alarms or sudden pressure spikes

Possible Causes:

• Kinetic (large orifice) function not working
• Air trapped due to incorrect orientation
• Valve undersized for rapid air movement

Solutions:

• Use combination air valves for both small and large air volumes
• Ensure vertical, upright installation with proper support
• Recalculate system parameters to confirm sizing adequacy

4. Corrosion or Premature Material Failure

Symptoms:

• Pitting or degradation of valve housing
• Stuck or immobile components
• Valve failure in less than expected service life

Possible Causes:

• Incompatible material for seawater or chemical exposure
• Poor-quality coatings or manufacturing defects
• Lack of routine flushing or cleaning in harsh environments

Solutions:

• Use corrosion-resistant materials such as Super Duplex, Titanium, 6Mo, or Aluminium Bronze
• Replace with valves specifically rated for seawater firefighting systems
• Add periodic maintenance procedures to remove buildup and prevent scaling

5. Erratic Valve Operation

Symptoms:

• Inconsistent release patterns
• Valve opens and closes rapidly (chatter)
• Audible banging or vibration

Possible Causes:

• Valve oversized or undersized
• Turbulent flow near valve
• Improper positioning or orientation

Solutions:

• Assess valve sizing based on real flow and pressure conditions
• Install valve away from elbows or tees to reduce turbulence
• Fit dampeners or arrestors if vibration persists

Preventative Maintenance Tips

• Inspect valves quarterly in high-demand environments
• Flush seawater lines regularly to prevent salt buildup
• Use only manufacturer-approved spare parts and kits
• Keep a maintenance log to track performance and replacements
• Schedule a full service annually for firewater and safety-critical systems