VALVE AUXILIARIES
Figure 5 : External leak in the weld heat effected zone of equalizing line led to external leak .
Figure 6 : Crack of the vent valve due to flow induced vibration .
Inspection and maintenance
Develop comprehensive inspection programs covering both the main valve and associated auxiliaries . Key aspects include :
• Regular cleaning , lubrication , and gasket replacement
• Integrity checks of piping and connections
• Visual inspections for damages and abnormalities
• Periodic non-destructive examination ( NDE ) methods , such as ultrasonic testing
• Flushing programs to minimize dead leg impacts
• Monitoring for corrosion , leaks or blockages
The frequency of inspection and maintenance should be tailored based on factors such as :
• Pipeline operating conditions
• Environmental factors
• Valve usage patterns
• Material durability and corrosion resistance
Conclusion
Ensuring the integrity and reliability of valve auxiliaries is as crucial as maintaining the main valve itself . Any risk imposed on these components can lead to unplanned outages and shutdowns . By implementing proper design , material selection , specification , inspection and maintenance practices , operators can ensure the readiness of valve auxiliaries and prolong their design life , ultimately sustaining operations and production .
Figure 7 :
condition and performance across the design life of the main line . To maintain the condition of the auxiliaries throughout the intended valve life , valve auxiliaries should be subject to robust inspection programs . These include visual inspections for signs of rust , external corrosion , oxidation , external leakages , damage , cracks and general condition and integrity of the coating . Non-destructive examination ( NDE ) methods such as wall thickness volumetric examination ( RT / UT ) are recommended to confirm the remaining wall thickness . When feasible , a cavity flushing program is recommended to drain accumulated products and minimize dead leg impacts . The frequency of inspection and maintenance for auxiliary systems can vary
depending on several key factors , including material of construction and pipeline operating conditions .
Specifications and design considerations
To prevent the highlighted risks and associated failures , valve auxiliaries should be designed and specified through robust standards . Key considerations include :
• Appropriate features for buried service ( e . g ., stem / shaft extensions , sealed interfaces )
• Suitable sealant injection fittings with safety features
• High-grade materials ( e . g ., SS 316L minimum for piping , valves and fittings )
• Consistent coating systems
• Proper configuration of drain , vent and sealant injection lines
About the authors Bader Al-Jarallah is a Valve Engineering Consultant at Saudi Aramco Central Engineering . He served as the Chairman of the Valve Engineering Standards Committee and is a member of several engineering standards committees . Bader holds a B . S . in Mechanical Engineering and an M . S . in Materials Engineering . Since joining Saudi Aramco in 2000 , he has dealt with various aspects of design , commissioning , operations , troubleshooting and maintenance .
Essam Arfaj is an Engineering Consultant with 25 years of experience in the oil and gas industry . His expertise spans technical leadership , management , professional engineering and human resources .
Mohanned Tarabzouni is a Piping and Valves Engineer in the Pipeline Technical Support Division of Saudi Aramco . He holds a B . S . in Mechanical Engineering and an M . S . in Pipelines , working for the Projects & Technical Support Department .
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