SH/T 0190-1992 Determination of the coefficient of friction of liquid lubricants (MM-200 method)

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.

Source limitations: The available source has unresolved roller dimensions, surface roughness, heating-tube and paddle dimensions, temperature tolerance and reference-oil standard designation. Ambiguous values are reproduced with explicit verification notes; they are not confirmed operating specifications. Check the original standard before use.

Card type: Test method

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

• Standard number: SH/T 0190-92
• Chinese title, translated: Determination of the coefficient of friction of liquid lubricants (MM-200 method)
• English name in the source: not found in the available source.
• Replacement relationship: replaces ZBF34 008-87.
• Approval/implementation: approved by China Petrochemical Corporation on 1992-05-20; implemented on 1992-05-20.

2. Scope and exclusions

• Applies to determining the coefficient of friction of rolling oils, drawing oils, emulsifying oils and similar liquid lubricants.
• Exclusions: not found in the available source.

3. Principle

A pair of steel test rollers with spherical contact surfaces, different diameters and different rotational speeds is installed on the test machine. The sample is introduced between the contact surfaces. The rollers operate under combined rolling and sliding friction. Applying a load produces a friction torque, from which the coefficient of friction of the sample is calculated.

4. Reagents and materials (purity / preparation)

• 5.1 Solvent oil: grade 190 specified in GB 1922.
• 5.2 Petroleum ether: 60~90 ℃, analytical grade.
• 4.7 Metallographic abrasive paper: grade W10.
• 4.8 Machine oil: N32 specified in GB 443.
• Appendix A, reference oils (supplementary):
  • Oil A: produced by Dalian Petrochemical Company; meets the N22 requirements of GB 443.
  • Oil B: oleic acid produced by Shanghai Yan'an Oil and Fat Factory, stated to meet Shanghai Q/HG-102-{5, Oleic Acid. The extracted standard number is uncertain and requires confirmation against the source standard (source-text extraction).
  • Reference-oil coefficient-of-friction ranges:
    • Oil A: low speed 0.083±0.003; high speed 0.075±0.003.
    • Oil B: low speed 0.058±0.003; high speed 0.049±0.003.

5. Apparatus

• 4.1 MM-200 wear tester:
  • Driven by a two-speed motor with speeds of 2870 r/min±20 r/min and 1440 r/min±10 r/min.
  • Applied-load range: 0~1960 N (0~200 kgf).
  • Upper roller speed: high speed 360 r/min, low speed 180 r/min; lower roller speed: high speed 400 r/min, low speed 200 r/min.
  • Equipped with scales indicating the applied load and friction torque (see Figure 1).
  • Install horizontally on a firm foundation to prevent vibration.
• 4.2 Test rollers:
  • The upper and lower rollers are annular; their contact surfaces are spherical, with a radius of curvature equal to the maximum radius of the ring.
  • Upper roller diameter: extracted as 40_[unreadable]OS mm; lower roller diameter: extracted as 50.8_[unreadable]05 mm. Both numerical specifications remain uncertain and require confirmation against the source standard (source-text extraction).
  • Roller thickness: 10 mm±0.02 mm; bore diameter extracted as 16+0.015.0. The bore specification is uncertain and requires confirmation against the source standard (source-text extraction).
  • Material: 40CrMnMo; hardness HRC48~54.
  • Roughness requirements: the extracted specifications for the friction surface, bore and side faces are unreadable and require confirmation against the source standard (source-text extraction).
• 4.3 Constant-temperature water bath: maximum operating temperature 95 ℃. The inlet and outlet circulation lines use latex tubing with an extracted specification of [unreadable prefix]7×2, connected to a heating coil made from copper tubing with an extracted specification of [unreadable prefix]6×1. These specifications require confirmation against the source standard (source-text extraction). The coil must fit conveniently into and out of the oil box.
• 4.4 Oil box and oil-box cover (see Figures 3 and 4).
• 4.5 Stirring paddle (see Figure 5).
• 4.6 Electric air dryer: 220 V, 450 W.
• Figure 3, oil box: galvanized sheet steel, thickness extracted as 0.7s. The numerical specification requires confirmation against the source standard (source-text extraction).
• Figure 4, oil-box cover: organic glass, thickness 3 mm.
• Figure 5, stirring paddle: galvanized sheet steel; thickness extracted as [unreadable prefix]7. Twist the two blades clockwise by an angle extracted as 3[unreadable suffix]. Both numerical specifications require confirmation against the source standard (source-text extraction).

6. Recommended operating conditions

• For oil-type lubricants, use the low-speed setting: upper roller 180 r/min, lower roller 200 r/min. The test-temperature text is extracted as 25 ℃±1090; this value is unresolved and requires confirmation against the source standard (source-text extraction).
• For emulsions, use the high-speed setting: upper roller 360 r/min, lower roller 400 r/min; test temperature 40 ℃±2 ℃. The extraction reads '40C 1 2C'; confirmation against the source standard is required (source-text extraction).
• Loading: apply the load continuously with the loading lever, reaching 1960 N (200 kgf) within 3 min.

7. Sampling and sample preparation

• 7.1 Pour about 180 mL of the thoroughly shaken sample into the oil box, immersing the lower roller to a depth of about 3 mm.
• Note: when measuring oil-type lubricants, if less than 180 mL of sample is available, oil may instead be applied to the upper and lower rollers with clean filter paper. The source states that the measured coefficient of friction is equally reliable, provided room temperature is within the specified test-temperature range.
• Other sampling and preparation details: not found in the available source.

8. Procedure

• 6.1 Clean the upper and lower rollers, oil box, oil-box cover, stirring paddle, heating coil and other parts that contact the sample with grade 190 solvent oil. Rinse again with petroleum ether, then dry with the electric air dryer.
• 6.2 Before using new rollers, polish their spherical surfaces with W10 metallographic abrasive paper at the machine's low-speed setting for 5 min. The extracted time reads '5nun' and requires confirmation against the source standard (source-text extraction). Run in under a load of 1960 N (200 kgf) for 30 min using N32 machine oil as the lubricant. Calibrate with reference oil before carrying out formal tests.
• 6.3 Check the water level in the constant-temperature bath, connect the heating coil, set the contact thermometer to the specified temperature, switch on the heater and start the motor-driven pump to circulate the water.
• 6.4 Before the test, turn the friction-torque flywheel by hand so that the shaft turns freely through two revolutions. Start the motor and run the tester unloaded for 2 min, then stop it.
• 7.1 Place the heating coil in the oil box and install the oil box on the tester. Pour about 180 mL of the thoroughly shaken sample into it, immersing the lower roller to a depth of about 3 mm.
• 7.2 Connect the loading mechanism and adjust the upper loading screw by hand to leave approximately 2 mm between the rollers. Install the oil-box cover.
• 7.3 When the sample reaches the specified temperature, start the motor and select the test conditions given in Section 6.
• 7.4 Apply the load continuously with the loading lever, reaching 1960 N (200 kgf) within 3 min. Record the friction torque at loads of 490 N (50 kgf), 980 N (100 kgf), 1470 N (150 kgf) and 1960 N (200 kgf). Hold the 1960 N load for 1 min, then record the friction torque again and observe its change. The source refers to the test-record table below it.
• 7.5 After recording the friction torque, remove the load with the loading lever, stop the machine and disconnect the power.
• 7.6 Remove the oil box and discard the sample. Clean the oil box, rollers and heating coil according to the specified procedure, first with solvent oil and then with petroleum ether. Dry with the electric air dryer for the next test.

9. Determination and calculation

• 8.1 Calculate the sample's coefficient of friction from the friction torque recorded immediately upon reaching the 1960 N (200 kgf) load.
• 8.2 Calculate the coefficient of friction μ using equation (1):
  • μ = M / (P·R)
  • Where M is the friction torque, N·cm; P is the load, N; and R is the radius of the lower roller, cm.
• With a test load P of 1960 N and a lower-roller radius of 2.54 cm, the coefficient-of-friction equation simplifies to equation (2):
  • μ = 0.000201 M

10. Precision

Judge the reliability of test results using the following provisions, at a confidence level of 95%.

• 9.1 Repeatability: for the same operator using the same tester under the specified conditions, the difference between two successive results on the same sample shall not exceed 3% of their mean.
• 9.2 Reproducibility: for different operators in two laboratories under the specified conditions, the difference between results on the same sample shall not exceed 11% of their mean. The extraction reads 'll%' and requires confirmation against the source standard (source-text extraction).

11. Report

Report the coefficient of friction of the tested sample to 0.0010.

12. References

• GB 443 Oils for L-AN total-loss lubrication systems.
• GB 1922 Solvent oil.
• Appendix A (supplementary), reference oils.
• Additional notes: technical coordination by the Research Institute of Petroleum Processing; drafted by the Refining Research Institute of Luoyang Petrochemical Engineering Corporation; principal drafter Fan Chuifan.

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 reference questions