SH/T 0649-1997 Marine lubricating oil corrosion test 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.

Card type: Test method

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

• Standard number: SH/T 0649-1997
• Chinese name: Marine lubricating oil corrosion test method
• English name: Marine lubricating oils — Test method of corrosiveness
• Replacement relationship: not provided in the available source
• Other: 2004 year confirmation; approved by China Petrochemical Corporation 1992-10-27, implemented 1998-07-01 (original text as such, the approval year number and the standard year number are inconsistent, requires confirmation against the source standard (source-text extraction))

2. Scope of application and non-applicability

• Scope of application: This standard specifies the method for determining the corrosion performance of marine lubricating oils using alloy test pieces of four materials; it is applicable to marine trunk piston diesel engine oils and marine crosshead diesel engine oils.
• Not applicable: not provided in the available source.

3. Method principle

In a test cup containing 170 mL sample, four alloy test pieces of different materials are immersed. The test cup is placed in a marine lubricating oil corrosion tester and kept at a constant temperature of 140 ℃ 100 h. The corrosion performance of the sample is evaluated according to the discoloration of the test pieces after the test.

4. Reagents and materials (purity / preparation)

• 5.1 Petroleum ether: 60～90 ℃, analytical reagent.
• 5.2 Anhydrous ethanol: analytical reagent.
• 4.2.2 Metallographic abrasive paper: specification W20, meeting the requirements of JB 3368.
• 4.2.3 Absorbent cotton.
• 4.2.4 Qualitative filter paper: diameter 11 cm.
• 4.2.1 Test piece: alloy material, length 60 mm±1 mm, width 15 mm±1 mm, thickness 2 mm±0.2 mm; each test piece has a hole of diameter 5 mm at the center 5 mm from the short edge. Test piece alloy grades:
  • Tin-based alloy test piece: ZSnSb11Cu6, meeting the requirements of GB/T 1174
  • Lead bronze alloy test piece: ZCuPb30, meeting the requirements of GB/T 1174
  • Tin bronze test piece: ZCuSn10P1, meeting the requirements of GB/T 1174
  • Aluminum-based alloy test piece: AlSn20Cu, meeting the requirements of GB/T 1151

5. Instruments and equipment

• 4.1.1 Marine lubricating oil corrosion tester: a solid heating device made of aluminum alloy. The bottom and surroundings of the heating body are heated by an electric heater with good durability, and are protected by insulation and heat-insulating layers. Under test conditions, it ensures a constant temperature accuracy of ±1 ℃, and can be used continuously for more than 100 h without loss of control. The heating body is uniformly arranged with 12 holes in the vertical direction (hole diameter 52 mm±1 mm, hole depth 160 mm), and the temperature of each hole position is balanced, with a temperature difference not greater than 0.5 ℃.
• 4.1.2 Test cup: made of glass, outer diameter 50 mm±1 mm, height 200 mm±2 mm, with a graduation line at 170 mL.
• 4.1.3 Support: made of glass. Column diameter 6 mm±0.5 mm, height 180 mm±2 mm, base diameter 40 mm±1 mm, with a protruding part at 75 mm from the base, used to support the hanging ring. See Figure 1.
• 4.1.4 Hanging ring: a glass ring, fitted over the protruding part of the support. There are four hooks equally spaced around the outer circumference, used for hanging the test pieces. See Figure 2.
• 4.1.5 Bamboo tweezers.

6. Recommended operating conditions

• Test temperature: 140 ℃±1 ℃
• Constant temperature time: 100 h
• Sample amount: 170 mL
• Preheating: after placing in the tester, preheat for 1 h then start timing
• Temperature recording: record the test temperature once every 2 h

7. Sampling and sample preparation

• Sample amount: 170 mL (pour into the test cup to the graduation line), and record the sample number.
• Test piece treatment (6.2): polish the six surfaces of the test piece with metallographic abrasive paper (W20) until the surface is smooth and free of marks, then hold the test piece with bamboo tweezers, repeatedly scrub it in petroleum ether with absorbent cotton until there is no residue on the surface of the test piece, then rinse with anhydrous ethanol. After treatment, the test piece is naturally dried and placed in a desiccator 24 h for later use.
• Note: When polishing and scrubbing the test piece, gloves should be worn to avoid direct contact with the skin.
• Vessel preparation (6.1): wash the test cup, support, and hanging ring in sequence with cleaning solution, then rinse with tap water and distilled water, and dry for later use.

8. Analysis procedure

• 7.1 Raise the temperature of the marine lubricating oil corrosion tester to 140 ℃±1 ℃.
• 7.2 Pour 170 mL sample into the test cup (to the graduation line), and record the sample number.
• 7.3 Put the hanging ring on the support, use bamboo tweezers to hang the four treated test pieces on the four hooks of the hanging ring respectively, and record the numbers of the four test pieces. Place this support into the test cup. Cover the mouth of the test cup with qualitative filter paper.
• 7.4 Place the test cup into the marine lubricating oil corrosion tester that has reached the specified temperature, preheat for 1 h then start timing, and record the test temperature once every 2 h.
• 7.5 After testing for 100 h, turn off the power and take out the test cup.
• 7.6 Take out the test pieces from the test cup, wash off the oil with petroleum ether, then rinse with anhydrous ethanol, and naturally dry.
• 7.7 Evaluate the corrosion performance of the sample according to the color change of the test pieces.

9. Qualitative and quantitative and calculation formula

• Result judgment (8.1 pass): all four test pieces are bright and colorless (compared with new pieces) or have colored streaks such as blue on the surface; within this range, they can be considered "pass", i.e., the sample corrosion performance is qualified.
• Result judgment (8.2 fail): if any one test piece has any degree of blackening, scaling, or flaky deposits on the surface, it is considered "fail", i.e., the sample corrosion performance is unqualified.
• Calculation formula: not provided in the available source.

10. Precision

Not provided in the available source.

11. Report

According to the evaluation of the color of the test pieces after the test, report the test result of the sample: sample corrosion performance "pass", or sample corrosion performance "fail".

12. Referenced documents

• GB/T 1151 Technical conditions for internal combustion engine main bearing shells and connecting rod bearing shells
• GB/T 1174 Cast bearing alloys
• JB 3368 Page-form metallographic abrasive paper

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