NB/SH/T 0904-2015 Determination of Oxidation Stability of Automatic Transmission Fluids

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: NB/SH/T 0904—2015
• Chinese title: Determination of Oxidation Stability of Automatic Transmission Fluids
• English title: Testing methods for oxidation stability of automatic transmission fluid
• Replacement relationship: This standard is first published (not provided in the available source regarding replacement of other standards)
• Drafting rules: Drafted according to the rules given in GB/T 1.1—2009
• Reference relationship: Prepared using the redrafting method with reference to JIS K2514-1996 "Determination of Oxidation Stability of Lubricating Oils", and the degree of consistency with JIS K2514-1996 is non-equivalent
• Differences from reference standard: The test principle is basically the same as the oxidation stability test part for internal combustion engine lubricating oils in Chapter 4 of JIS K2514-1996, but the test conditions are different; JIS K2514-1996 specifies test temperature 165.5 ℃ and test time 24 h; this standard, according to JASO M315 "Automatic Transmission Fluid Product Specification", modifies the test temperature to 150 ℃ and the test time to 96 h
• Publication/implementation: Published on 2015-10-27, implemented on 2016-03-01
• Issuing authority: National Energy Administration
• Secretariat: National Technical Committee for Standardization of Petroleum Products and Lubricants, Subcommittee on Petroleum Fuels and Lubricants (SAC/TC 280/SC 1)
• Proposed by: China Petrochemical Corporation
• Drafting organization: Dalian Lubricant Research and Development Center of PetroChina Company Limited
• Main drafter: Zhao Zhiyu

2. Scope of application and non-applicability

• Scope of application: This standard specifies a test method for evaluating the oxidation stability of automatic transmission fluids; it is applicable to automatic transmission fluids and related lubricating oil products.
• Non-applicability: not provided in the available source.

3. Method principle

Immerse steel and copper catalysts and a glass rod in the test oil, and stir the test oil at a temperature of 150 ℃ for 96 h to oxidize it. Measure the kinematic viscosity and acid value of the oxidized oil and compare them with the unoxidized oil, and calculate the viscosity ratio and the change in acid value. At the same time, observe the adhesion state of lacquer-like substances or sludge on the glass rod. (Note: This paragraph in the original text has heavy source-text extraction noise, and individual words require confirmation against the source standard (source-text extraction).)

4. Reagents and materials (purity / preparation)

4.1 Reagents

• n-Heptane: analytical grade.
• Petroleum ether: meets the requirements of GB/T 15894, boiling range 60 ℃~90 ℃, analytical grade.
• Water: meets the grade three water requirements specified in GB/T 6682—2008.

4.2 Materials

• Catalysts:
  • Steel: material Q195 or Q215 specified in GB/T 3094—2000, thickness 0.5 mm, width 26 mm, length 121.4 mm.
  • Copper: material T2 specified in GB/T 4423—2007, thickness 0.5 mm, width 26 mm, length 60.4 mm.
  • Note 1: Drill fixing holes at both ends of the steel and copper catalysts (φ1.0 mm).
  • Note 2: Catalysts of the shape shown in Figure 7 may also be used. Bend the copper catalyst at the fold lines at both ends (marks formed by bending) into claws, make holes at both ends of the steel catalyst for inserting the claws, and when combining the two catalysts, insert the copper catalyst claws into the grooves/holes of the steel catalyst, and bend the claws down firmly along the fold lines to fix them.
• Abrasive material: The abrasive material is alumina abrasive or garnet abrasive meeting the requirements of GB/T 15305.1, with a particle size of P400 abrasive cloth or abrasive paper.
• Cotton: medical absorbent cotton meeting the requirements of YY 0330.

5. Apparatus and equipment

• The lubricating oil oxidation stability tester is as shown in Figure 1 (schematic diagram, unit: millimeters). The components labeled in Figure 1 include: 1— motor; 2— rotor; 3— oil storage beaker holder; 4— insulation material; 5— insulation wall; 6— thermometer; 7— temperature regulator; 8— stirring rod; 9— glass oil storage beaker; 10— overflow tube; 13— bath; 15— glass rod; 16— control panel. (Numbers 11, 12, 14 not provided in the available source)
• 5.1 Heating bath: equipped with a stirrer, heater, and temperature regulator. The oil bath temperature should be maintained at 150.0 ℃±0.5 ℃, and the height from the top of the heating bath to the bottom of the oil storage beaker should be set to 120 mm, so that the oil storage beaker is immersed in the bath liquid by at least 90 mm.
• 5.2 Thermometer: a GB-59 rod-type thermometer meeting the requirements specified in GB/T 514—2005.
• 5.3 Glass oil storage beaker and oil storage beaker cover
  • 5.3.1 Glass oil storage beaker: as shown in Figure 2 (dimension labels include φ84±2, φ73±2, etc., source-text extraction has heavy noise, requires confirmation against the source standard (source-text extraction)).
  • 5.3.2 Oil storage beaker cover: shape and dimensions as shown in Figure 3, made of phenolic resin, with insertion holes for the stirring rod and glass rod on the cover. Note: A deformed or damaged cover can change the internal air replacement ratio, which may sometimes cause deviation in test results, and attention should be paid to this.
• 5.4 Stirring rod: shape and dimensions as shown in Figure 4, made of borosilicate glass or 0Cr18Ni9 stainless steel (304 stainless steel).
• 5.5 Rotor: shape as shown in Figure 1, inserted into the stirring rod from below, fixed with a chuck at a position 10 mm from the bottom of the oil storage beaker. Rotate at 1300 r/min±15 r/min, in the direction in which the blades press down the test oil.
• 5.6 Glass rod: shape and dimensions as shown in Figure 5, made of borosilicate glass.

6. Recommended operating conditions

• Test temperature: 150.0 ℃±0.5 ℃ (the heating bath temperature should be controlled at 150.0 ℃±0.5 ℃).
• Test time: 96 h.
• Stirring speed: 1300 r/min±15 r/min, in the direction in which the blades press down the test oil.
• Note: When an individual product standard differs from this standard, operate according to its specified temperature; when the test time in an individual product standard differs from this standard, operate according to its specified time.

7. Sampling and sample preparation

• Test oil amount: Into two oil storage beakers containing the catalysts, pour test oil 250 mL separately at room temperature.
• The samples are divided into unoxidized oil (test sample before the oxidation test) and oxidized oil (test sample after the oxidation test).
• Note: If it is known that the difference between the kinematic viscosity ratios of two measurement results does not exceed 14% of the average value, and the difference between the acid values before and after measurement is within the allowable difference in Table 1, and the adhesion degree is consistent, one oil storage beaker may also be used for testing; in this case, the result in Chapter 9 takes the result of one test oil.

8. Analysis procedure

• 7.1 Place the oil storage beaker, stirring rod, and glass rod in chromic acid cleaning solution or an equivalent cleaning agent, soak for at least 2 h, rinse thoroughly with tap water, then rinse several times with distilled water and dry.
  • Note 1: If the stirring rod is made of stainless steel, clean it with solvent and then dry it.
  • Note 2: When chromic acid cleaning solution is discarded, harmless treatment of the waste liquid should be carried out.
• 7.2 Use absorbent cotton dipped in an appropriate solvent (petroleum ether, n-heptane, etc.) to carefully wipe the two catalysts, then grind out a new surface with abrasive cloth or abrasive paper, then completely wipe off the grinding powder with absorbent cotton, and assemble as shown in Figure 6. The ground catalysts should be used for the test immediately. When touching the ground catalysts, clean dry absorbent cotton or cotton gloves should be used; do not touch them directly with hands.
• 7.3 The temperature of the heating bath should be controlled at 150.0 ℃±0.5 ℃. Insert the thermometer as deeply as possible within the range where the temperature can be read.
• 8.1 Into two oil storage beakers containing the catalysts, pour test oil 250 mL separately at room temperature, and cover the two oil storage beakers. After the stirring rod passes through the cover, cover the oil storage beaker, install the stirring rod on the rotor so that the lower end of the blades is at least 10 mm from the bottom of the container, and then install the glass rod. After installing the stirring rod and glass rod, do not directly touch with hands the parts immersed in the test oil.
• 8.2 Rotate the stirring rod at a speed of 1300 r/min±15 r/min in the direction that presses down the test oil, and stir the test oil. Record the time when the stirring rod starts rotating as the test start time.
• 8.3 After 96 h, remove the oil storage beaker from the heating bath, withdraw the glass rod, remove the catalysts with clean tweezers, and cool the oxidized oil to room temperature.
• 8.4 For the unoxidized oil, the cooled oxidized oil, and the glass rod, promptly perform the following tests:
  • 8.4.1 Determine the kinematic viscosity of the unoxidized oil and oxidized oil at 40 ℃ according to the provisions of GB/T 265.
  • 8.4.2 Determine the acid value of the unoxidized oil and oxidized oil according to the provisions of GB/T 7304.
  • 8.4.3 Wash the glass rod with petroleum ether, remove the oxidized oil, and dry. Check whether lacquer-like or sludge-like substances are attached; if there is attached matter, compare it with the glass rod color comparison chart (Figure 8) to obtain the color number corresponding to the degree of coloration of the glass rod, and record it.

9. Qualitative and quantitative determination and calculation formulas

9.1 Viscosity ratio

• 9.1.1 Calculate the viscosity ratio from the kinematic viscosity of the test oil before and after oxidation according to formula (1), retaining two decimal places.
  • R = D2 / D1 (Formula 1)
  • Where: R— viscosity ratio; D1—40 ℃ kinematic viscosity of the unoxidized oil, in square millimeters per second (mm²/s); D2—40 ℃ kinematic viscosity of the oxidized oil, in square millimeters per second (mm²/s).
  • (Note: In the original text source-text extraction, the arrangement of D1, D2 and the formula is suspected to be misaligned, requires confirmation against the source standard (source-text extraction).)
• 9.1.2 When the difference between two test results does not exceed 14% of the average of the two test results, the average of the two test results is recorded as the viscosity ratio.
• 9.1.3 When the difference between the two test results exceeds 14% of the average of the two test results, the group of tests is considered invalid.

9.2 Acid value increase

Calculate the difference in acid value of the test oil before and after oxidation, retaining three significant figures. However, when it is less than 1 mgKOH/g, retain two decimal places. When the difference between the two test results does not exceed the tolerance in Table 1, the average of the two test results is recorded as the acid value increase. When the difference between the two test results exceeds the tolerance in Table 1, the group of tests is considered invalid.

Table 1 Tolerance values

9.3 Adhesion degree

• 9.3.1 According to Figure 8, the degree of coloration of the glass rod is divided into 9 levels.
• 9.3.2 The adhesion state of the paint-like or mud-like substance on the glass rod can be classified according to Table 2, and the result is expressed as adhesion degree.
• 9.3.3 When the two test results are inconsistent, take the side with the larger color number in the color comparison card as the result.

Table 2 Classification standard for adhesion degree

10. Precision

• Viscosity ratio: When the difference between the two test results does not exceed 14% of the average of the two test results, take the average as the result; when it exceeds 14%, the group of tests is invalid (see 9.1.2, 9.1.3).
• Acid value increase: When the difference between the two test results does not exceed the tolerance in Table 1, take the average as the result; when it exceeds the tolerance in Table 1, the group of tests is invalid (see 9.2, Table 1).
• Adhesion degree: When the two test results are inconsistent, take the side with the larger color number in the color comparison card as the result (see 9.3.3).
• Other precision indicators: not provided in the available source.

11. Report

The test result report shall at least include the following contents:

• Laboratory information and test date;
• Application of this standard;
• Name of the test oil;
• Results obtained in Chapter 9;
• Special matters.

12. Reference documents

• GB/T 265 Petroleum products—Determination of kinematic viscosity and calculation of dynamic viscosity
• GB/T 514—2005 Technical conditions for glass liquid thermometers for petroleum product testing
• GB/T 3094—2000 Cold-drawn special-shaped steel tubes
• GB/T 4423—2007 Copper and copper alloy drawn rods
• GB/T 6682—2008 Specifications and test methods for water for analytical laboratory use
• GB/T 7304 Determination of acid value of petroleum products—Potentiometric titration method
• GB/T 15305.1 Coated abrasives—Abrasive paper
• GB/T 15894 Chemical reagent—Petroleum ether (the source text writes CB/T 15894, requires confirmation against the source standard (source-text extraction))
• YY 0330 Medical absorbent cotton
• Reference: JIS K2514-1996 "Determination of oxidation stability of lubricating oils"
• Reference: JASO M315 "Automatic transmission fluid product specifications"

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