Determine oxidation stability of steam turbine oils by rotating pressure vessel
16. Preparation of Apparatus
16.1 Catalyst Preparation - Before use, polish approximately 3 m of the copper wire with a silicon carbide abrasive cloth and wipe free from abrasives with a clean, dry cloth. Wind the wire into a coil having an outside diameter 44 to 48 mm and weight of 55.6 more or less 0.3 g and stretched to a height of 40 to 42 mm. Clean the coil thoroughly with isopropyl alcohol, air-dry, and insert inside the glass sample container by a turning motion, if necessary. A new coil is used for each sample. For extended storage, the prepared coil may be packaged in a dry, inert atmosphere. For overnight storage (less than 24 h), the coils may be stored in n-Heptane or cyclo-Hexane.
NOTE 10 - Commercially available and prepackaged coils prepared as described in 8.1 can also be used for the test.
16.2 Cleaning of Pressure Chamber - After a test is completed, remove any deposits from inside of the chamber by using the forceps and the cleaning pad to scrub off the deposits. Spray clean cold water down the walls of the chamber using the aspiration cleaning bottle until the water level almost reaches the oxygen inlet hole in the upper bottom of the chamber. After a few minutes, use the empty aspiration cleaning bottle to remove the water mixture by compressing the bottle then dip the water extraction tube on the bottle into the water and release the compression. Varclean can be used for difficult deposits. Rinse the chamber several times with water and one final rinse with methanol. To ensure all the water has been removed from the oxygen inlet, press the oxygen fill valve several times to blow out any water. Dry the inside with a paper towel.
16.3 Cleaning of Glass Container - Drain and rinse with a suitable solvent (for example, cyclo-hexane or acetone). Soak or scrub in a Varclean solution. Brush thoroughly and flush thoroughly with tap water. Rinse with isopropyl alcohol, followed by distilled water and air dry. If any insolubles remain, soak overnight in Varclean10 and repeat the above procedure.
16.4 Cleaning of Polytetrafluoroethylene (PTFE) Disk, Magnetic Cup and Spring Clip - Remove any residual oil with a suitable solvent and clean by brushing with Varclean. Rinse thoroughly with tap water, followed by distilled water rinse and air dry.
