Air-Cooled Heat Exchangers
Refer to vendor's recommendations.
The following are recommendations that can be used for protecting finned air coolers:
1) Pump light oil through the tubes. Drain and seal or spray internally with Shell Ensis H oil with 2% VSI 8233 and cap.
2) Open, drain the tubes, dry and close. Fill with inert gas 0.5 bar(g). Verify pressure periodically.
3) Spray the exterior parts with a suitable rust preventive such as Shell Ensis Oil 158.
4) Coat bolts with a heavy grease such as Shell Rhodina.
5) Damaging of finned tubes has to be prevented. Therefore leave the tube bundles in the storage area for as long as possible, properly protected by means of steel plates covering the protection screen of the bundles. These plates shall be reinstalled when tube bundles are fitted and shall be removed during precommissioning activities.
Motors shall have separate preparation and follow up as described under motors (9.10).
Operating mechanisms on the louvers shall be coated with a heavy grease such as Shell Rhodina, to ensure operability when put to service. Operate louvers periodically and verify functioning. Since airfin coolers are generally installed at elevated positions, attention shall be paid to connect earthing at an early stage for lightning protection.
Since deformation of louvers may result in blocking of louver vanes, care should be taken during bolting up. Protection steel plate shall only be removed prior to final installation.
During installation of fans and prior to operating, grease-lines shall be loosened at the bearing ends and be pumped through until clean grease comes out of the grease line ends.
The fan blades and blade insert reinforcement shall be protected by Shell Ensis Oil 158 or Autoseal 1894.
If idle time exceeds two years, grease will be changed and ball joints checked/regreased.
Protect the hubs from infiltration of dust, sand and water. Protect the bearing discharge screws by grease and cover these with rubber bands or denso tape.
The fan shall be rotated periodically.
V-Belts shall be stored in a loose condition in a dry stock room away from direct heat and sunlight.
They will be properly tagged for identification and installed only shortly before precommissioning.
Separately lubricated gears shall be filled with Shell Ensis Oil 158 with 2% VSI 8235. The oil shall be applied by circulating, flushing or brushing. All openings shall be closed thoroughly afterwards.
Shell and Tube Heat Exchangers
Refer to vendor's recommendations.
The exchanger shall be drained and dried. Blank off all nozzles and plug all vents and drains.
Coat all exposed bolts and flanges with heavy grease (such as Shell Rhodina). Determine the exterior protective measures as dictated. Provide when specified nitrogen pressure of 0.5 bar(g). Verify blanket pressure.
If nitrogen supply is impractical, dry air can be used combined with moisture absorbents. The equipment shall be
pressurized as for nitrogen. Every month the moisture absorbent shall be checked and replaced if required. Location of moisture absorbent shall be noted so that it can be removed easily and completely when the commissioning is started. Other methods can also be selected in conjunction with client representative.
