SH/T 0643-1997 Determination of water spray resistance of lubricating grease

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 name / replacement relationship

• Standard number: SH/T 0643-1997
• Chinese title: Determination of water spray resistance of lubricating grease
• English title: Lubricating greases — Determination of resistance to water spray
• Replacement relationship: not provided in the available source (the foreword only states equivalent adoption of ASTM D4049-93, and does not mention replacement of an old standard)
• Adoption relationship: equivalent adoption of ASTM D4049-93 "Determination of water spray resistance of lubricating grease"
• Main differences from ASTM D4049-93: the washing solvent naphtha is changed from conforming to ASTM D235 "Solvent naphtha (petroleum spirit) (hydrocarbon dry-cleaning solvent naphtha)" specification to conforming to SH 0005 "Solvent naphtha for paint industry" standard; because the two solvent naphthas are similar in quality and are only used for cleaning instruments, a domestic solvent naphtha is used instead
• Proposed by / administered by: Petrochemical Research Institute of China Petrochemical Corporation
• Drafting organization: Petrochemical Research Institute of China Petrochemical Corporation
• Main drafter: Li Xianming
• Approval date: 1997-07-12
• Implementation date: 1997-12-01

2. Scope of application and non-application

• 1.1 This standard evaluates, under specified test conditions, the adhesion ability of lubricating grease to metal surfaces when water is sprayed on the lubricating grease.
• 1.2 Values expressed in International System of Units (SI) are considered standard values. Values given in parentheses are for reference only.
• 1.3 This standard does not address all safety issues associated with its use. Users of this standard are responsible for establishing appropriate safety and health measures before use and for determining the applicable restricted scope.
• Non-application scope: not provided in the available source.

3. Method principle

A lubricating grease is coated on a stainless steel plate and subjected to water spray at the specified test temperature and pressure. After 5min, the percentage spray mass loss of the lubricating grease is determined as a measure of the water spray resistance of the lubricating grease. (Chapter 3 Method summary)

4. Reagents and materials (purity / preparation)

• 6.1 Reagents
  • n-Heptane: analytical reagent. Note: flammable, harmful if inhaled.
• 6.2 Materials
  • Solvent naphtha: conforms to SH 0005 "Solvent naphtha for paint industry" standard. Note: flammable, vapors harmful.
  • Adoption note: solvent naphtha replaces ASTM D235 solvent naphtha (petroleum spirit) (hydrocarbon dry-cleaning solvent naphtha).
• Preparation method: not provided in the available source.

5. Apparatus and equipment

• 5.1 Stainless steel plate: as shown in Figure 1 (the source contains a figure; dimensions are in the original figure).
• 5.2 Mold: used for coating lubricating grease on the stainless steel plate, as shown in Figure 2 (the source contains a figure).
• 5.3 Water spray apparatus: as shown in Figure 3. The labeled components in the figure include:
  1. Pressure gauge (0 to 414kPa)
  2. Spray cover (plexiglass)
  3. Water tank
  4. Circulating gear pump
  5. Drain pipe
  6. Motor
  7. Shutoff valve
  8. High-pressure hose
  9. Bypass needle valve
  10. Nozzle
  11. Heater
• 5.4 Nozzle: as shown in Figure 4. The labeled components in the figure include: 1— cap; 2— blade; 3— body; 6.35 (1/4") standard pipe thread.
• 5.5 Thermometer or thermocouple: the thermometer used to measure the water spray temperature shall be placed in a position that does not affect the spray pattern.

6. Recommended operating conditions

• Water tank water temperature: 38℃±0.5℃
• Water circulation time: 2 to 3min (after reaching 38℃±0.5℃, allow the water temperature to equilibrate before spraying)
• Pump pressure: 276kPa±7kPa (40psi±1psi)
• Bypass valve position requirement: must be before the pressure gauge, not between the pressure gauge and the nozzle
• Spray time: 5min±15s
• Drying conditions: in an oven at 66℃±1℃ for 1h±5min (the drying temperature is garbled in the source transcription; its displayed interpretation is provisional)
• Lubricating grease coating thickness: 0.794mm
• Amount of water added: at least 8000mL tap water

7. Sampling and specimen preparation

• 7.1 Clean the stainless steel plate with a brush and solvent naphtha, then rinse with n-heptane, and dry in air.
• 7.2 Rinse the water tank clean with water, and wipe off residual oil film on the surface of the water tank and the surface of the spray chamber.
• 7.2.1 After each test, clean the apparatus in accordance with clause 7.2.
• 8.1 Weigh the mass of the clean stainless steel plate to the nearest 0.1g, record as M1, then use a metal mold (as shown in Figure 2) to coat a lubricating grease layer of thickness 0.794mm on the stainless steel plate. Remove lubricating grease on the stainless steel plate that extends beyond the scribed lines. Weigh again and record as M2.
• Sampling method: not provided in the available source.

8. Analytical procedure

• 8.1 Weigh the mass of the clean stainless steel plate to the nearest 0.1g, record as M1, then use a metal mold to coat a lubricating grease layer of thickness 0.794mm on the stainless steel plate. Remove lubricating grease on the stainless steel plate that extends beyond the scribed lines. Weigh again and record as M2.
• 8.2 Add at least 8000mL tap water to the water tank, and adjust the temperature to 38℃±0.5℃. When the water temperature in the water tank reaches 38℃±0.5℃, circulate the water for 2 to 3min, so that the water temperature equilibrates before spraying onto the stainless steel plate. Use the bypass valve to adjust the pump pressure to 276kPa±7kPa (40psi±1psi). The bypass valve must be before the pressure gauge, not between the pressure gauge and the nozzle. Turn off the motor.
• 8.3 Insert the stainless steel plate, making sure that the stainless steel plate is placed horizontally and centered below the nozzle. Start the motor and spray water onto the stainless steel plate for 5min±15s.
• 8.4 Turn off the motor to stop spraying, and remove the stainless steel plate. Remove excess lubricating grease outside the scribed lines on the stainless steel plate, along the edges, and at the bottom of the stainless steel plate. Place the stainless steel plate horizontally in an oven at 66℃±1℃ for 1h±5min (the drying temperature is garbled in the source transcription and remains unverified).
• 8.5 Remove the stainless steel plate from the oven and allow it to cool to room temperature. Weigh the stainless steel plate again and record as M3.

9. Qualitative and quantitative determination and calculation formula

The percentage spray mass loss of the lubricating grease x[%(m/m)] is calculated according to formula (1):

x = (m2 − m3) / (m2 − m1) × 100

Where:

• m1 — initial mass of the clean stainless steel plate, g
• m2 — mass of the stainless steel plate plus lubricating grease before spraying, g
• m3 — mass of the stainless steel plate plus lubricating grease after spraying, g

(In the source source-text extraction, the unit symbols for m1, m2, and m3 contain noise, such as "B+", "9", and "Ko"; requires confirmation against the source standard (source-text extraction); according to context they should be g)

10. Precision

• 10.1 Judge the reliability of test results according to the following provisions (95% confidence level).
  • 10.1.1 Repeatability: under long-term, normal, and correct operation in accordance with this standard, the difference between two test results obtained by the same operator using one apparatus on the same test material under the specified operating conditions shall not exceed 6.0% of their average value.
  • 10.1.2 Reproducibility: under long-term, normal, and correct operation in accordance with this standard, the difference between two single and independent test results obtained by different operators in different laboratories on the same test material shall not exceed 18.0% of their average value.
• 10.2 Bias: there is no bias in the procedure of this test method, because the spray mass loss value depends only on the test method itself.

11. Report

Report the percentage spray mass loss calculated according to Chapter 9 as the result.

12. Referenced documents

• SH 0005 Solvent naphtha for paint industry
• ASTM D4049-93 (equivalent adoption object, see foreword)
• ASTM D235 (mentioned in the foreword, the replaced solvent naphtha specification)

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 Q&A reference