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Maintenance
• Inspection QA / QC will indicate on the inventory sheet which bundles need to be re-sprayed with rust inhibitor .
Pressurized N2 canister . Photo courtesy of Saudi Aramco .
• All tube bundles stored at the facility shop yard will be protected using a rust inhibitor that will be applied by spraying .
• Blow dries the surface to be sprayed using compressed air .
• Apply a liberal spray coating of the inhibitor to all surfaces that will rust .
• Apply a coating of grease to all gasket surfaces
• On carbon steel tube bundles that have been tube side tested , the ID of the tubes require to be blown dry and have rust inhibitor sprayed in each tube from both ends . ( The actual application of the rust inhibitor shall be done outside the shop preferably in the hydrojetting area ( Open yard )
• After the bundle is sprayed and approved for storage by the Shop Supervisor and Inspection QA / QC Team , an inventory and inspection tag will be added . It is advisable to store the tube bundle in close area warehouse and / or use heat shrink wrapping when stored in open yards .
• It will be the responsibility of proponent Engineer / Inspection QA / QC to inspect the stored bundles .
• Inspection QA / QC will check and verify each bundle against the inventory and mark the tag on the bundle that has been inspected including signing the inventory sheet .
Sample of an N2 canister fabrication drawing . For the full resolution , please contact editor at i . mukha @ kci-world . com .
B ) Using pressurized nitrogen ( N2 ) canister
• Shop Supervisor to develop and inventory sheet of all tube bundles at the facility shop yard .
• Determine the required canister dimensions that will fit the stored bundle .
• The canister shall be visually inspected for any defects ( Corrosion , coating failure , lifting lugs damage , weld seams imperfection , sliding bar damaged , etc .)
• Flanged connections and all other machined surfaces area will be protected using an appropriate lubricant with rust preventive compound such as Cortec VpCI-369 or equivalent .
• Place the bundle inside the canister and close it using flanges and seal compound .
• Shop personnel should ensure a proper pressure gauge is installed on top of the canister including it has calibration sticker .
• Depressurize the canister and then repressurize with nitrogen ( N2 ) until pressure gauge reaches 2 to 5 Psig .
• It will be the responsibility of Proponent Engineer / Inspector QA / QC to inspect the stored bundles
• Inspection QA / QC will frequently check and verify each canister pressure reading and log it and sign on the inventory sheet .
References
1 . SA MSSD Shop Department – Shop Heat Exchanger Bundle Storage Procedure
2 . API 660 – Shell and Tube Heat Exchangers for General Refinery Services
3 . ASME PCC-2 - Repair of Pressure Equipment and
Piping 4 . NB23 - National Board Inspection Code
About the author
Miguel Gutierrez is a Senior Mechanical Engineer with over 30 years of experience in the oil and gas industry , particularly in the
Downstream Business showcasing his expertise in stationary equipment . His focus on piping / pipelines , pressure vessels , heat exchangers and storage tanks , along with hands-on troubleshooting during plant operations and turnarounds , reflects a comprehensive skill set . His international experience in Venezuela , the Caribbean Basin and the last 18 years in the Middle East adds a global dimension to his professional profile .
22 Heat Exchanger World March 2025 www . heat-exchanger-world . com