SH/T 0560-1993 Test method for thermal stability of lubricating oils

AI-translated method card — human verification pending. This is not an official translation of the standard. Unclear source values remain unverified; check the original standard and product certificate before use.

Card type: Test method

1. Method number / full title / English title / replacement relationship

• Standard number: SH/T 0560-93
• Chinese title: Test method for thermal stability of lubricating oils
• English title: not provided in the available source
• Replacement relationship: not provided in the available source (the source reads '(confirmed in 20P4)', suspected to mean 'confirmed in 2004'; confirmation is pending (source-text extraction)).
• Approval/implementation: approved by China Petrochemical Corporation on 1993-06-” (the date is suspected source-text extraction noise and requires confirmation (source-text extraction)); implemented on 1994-05-01.
• Standard used as a reference: Japanese Industrial Standard JIS K2540-1989, Test method for thermal stability of lubricating oils.

2. Scope and exclusions

• This standard specifies a test method for the thermal stability of lubricating oils.
• This standard applies to mineral-oil-based and synthetic lubricating oils.
• Exclusions: not provided in the available source.

3. Principle

At the temperature specified in the product standard, place two test cups, each containing 20g of sample, on the turntable in a lubricating-oil thermal-stability oven that has reached the specified temperature. Rotate at 5～6r/min. After the time specified in the product standard, visually examine the cooled samples and the bottoms of the test cups for sediment to assess thermal stability.

4. Reagents and materials (purity / preparation)

• 4.2.1 Solvent oil: meeting the requirements of SH 0005.
• 4.2.2 Distilled water: double-distilled or ion-exchanged water.
• Other reagents: not provided in the available source.

5. Apparatus

• 4.1.1 Lubricating-oil thermal-stability oven (see Figure 1): a rectangular, double-walled, electrically heated constant-temperature oven capable of temperature control within ±1℃. The front has a tightly closing, double-walled hinged door with a double-glazed viewing window measuring 150mm×150 (unit apparently missing; requires confirmation (source-text extraction)) for observing the temperature and the interior. A switchable lamp is fitted on an inside wall. Exhaust openings at the top have a total area of 1.3～12.9cm² (the value may contain source-text extraction noise; requires confirmation (source-text extraction)); two air inlet openings at the bottom each have a total area greater than 1.3cm², allowing natural-convection ventilation. A motor mounted on the oven drives a vertical shaft suspended centrally in its upper interior, rotating the turntable fitted to the shaft at 5～6r/min.
• 4.1.2 Turntable: construction and dimensions as shown in Figure 2; a flat, circular aluminium-alloy plate of diameter 250mm. It has 9 circular positions for test cups, with φ3 and φ9 circular ventilation holes on their inner and outer sides (units apparently missing; require confirmation (source-text extraction)). Reinforcing ribs between the cup positions strengthen the turntable and secure the cups. A central mechanism fixes the turntable to the shaft; ensure that the turntable is level when installed.
• 4.1.3 Thermometer: see Appendix A.
• 4.1.4 Test cup: a transparent, flat-bottomed glass cup with a fire-finished level rim; internal diameter 51～55mm, external height 55～59mm, wall thickness 1.0～2.0mm; heat-resistant to a temperature no lower than 200℃. A frosted band 10mm high and 25mm wide is located 10mm below the rim.
• 4.1.5 Balance: sensitivity 0.5g.
• 4.1.6 Desiccator: diameter 300mm.
• 4.1.7 Fluorescent desk lamp.

6. Recommended operating conditions

• Test temperature: the temperature specified in the product standard, controlled within ±1℃ of the specified test temperature.
• Turntable speed: 5～6r/min.
• Test duration: as specified in the product standard.
• Sample amount: 20g±1g (weighed to the nearest 0.1g).
• The lower end of the thermometer mercury bulb is approximately 2～3mm above the bottom of the test cup.
• Start of timing: start when the sample temperature reaches 1℃ below the specified temperature.

7. Sampling and sample preparation

• 5.2 Sample preparation: visual examination should show no water, sediment or foreign matter; otherwise remove them by centrifuging or filtration.
• 5.1 Preparation of test cups: wash with solvent oil to remove oil, traces of gum or residues from the previous test. If carbonaceous residue is present, soak in chromic acid cleaning solution for 2～3h, then clean with tap water and detergent, rinse finally with distilled water and dry in an oven before use.
• Note: a cup whose walls still contain deposits after cleaning must not be reused.

8. Analytical procedure

• 5.3 Adjustment of test temperature: adjust the oven so that the turntable is level. Place a test cup containing 20g±1g of sample (weighed to the nearest 0.1g) for temperature measurement at the designated position on the turntable. Insert the thermometer so that the lower end of its mercury bulb is approximately 2～3mm above the bottom of the cup, and secure the thermometer to the shaft support. Start the motor to rotate the turntable at 5～6r/min. Adjust the oven temperature controller to keep the sample within ±1℃ of the specified test temperature. When the temperature is stable, stop the turntable, open the oven door and remove the cup, then restart the motor so the turntable continues rotating. Fix the temperature-control setting to maintain a constant oven temperature.
  • Note ①: if the test temperature is the same as the temperature used for sample adjustment, do not readjust it; regard the oven temperature as the same as in the previous determination.
  • Note ②: when different samples are tested simultaneously, select the sample with the highest viscosity or density for temperature measurement.
• 6.1 Weigh 20g±1g of sample (to the nearest 0.1g) into each of three clean, dry test cups. Place all the cups in the cup positions on the turntable. Insert the thermometer into one cup used for temperature measurement as specified in 5.3, and secure it to the shaft support. Close the oven door and start the motor to rotate the turntable.
• 6.2 Start timing when the sample temperature reaches 1℃ below the specified temperature. Maintain constant temperature for the specified test duration. To observe the sample temperature and the interior during the test, switch on the lamp and stop the turntable, then observe through the window; do not open the oven door. After observation, promptly restart the turntable and switch off the lamp. Throughout the test, the temperature-measurement sample must remain within ±1℃ of the specified test temperature; otherwise the test is invalid.
  • Note: samples requiring different test durations must not be tested simultaneously.
• 6.3 At the end of the specified time, remove the two cups without thermometers and place them in a desiccator. Move the desiccator to a dark location until the samples cool to room temperature. Examine the cooled samples and the bottoms of the cups for sediment by transmitted light. If the observation is unclear, use a fluorescent lamp to judge whether sediment is present.

9. Qualitative and quantitative determination and calculation

• 7.1 Assessment: report 'no sediment' if neither of the two parallel samples nor the bottoms of their test cups show sediment; otherwise report 'sediment present'. If the results disagree, repeat the procedure in 6.1～6.3 until the results agree. Take two matching parallel results as the test result.
• 7.2 Report the test temperature and test duration with the result.
• Calculation equation: not provided in the available source.

10. Precision

Not provided in the available source.

11. Report

• Report the test temperature and test duration with the result (see 7.2).
• Other reporting requirements: not provided in the available source.

12. Referenced documents

• SH 0005 Solvent oil for the paint industry
• Standard used as a reference: JIS K2540-1989, Test method for thermal stability of lubricating oils.

13. Source and verification

This page is an AI translation of the available Chinese method card. Human verification is pending. It is not an official translation of the standard. Check the source standard and product certificate before use.

14. Quick questions and answers