SH/T 0330-1992 Determination of mechanical impurities in lubricating grease (extraction method)

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Card type: Test method

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

• Standard number: SH/T 0330-92
• Full title: Determination of mechanical impurities in lubricating grease (extraction method)
• English name: not provided in the available source
• Replacement relationship: replaces SY 2709-62(82)
• Other: approved in 1992-05-20, implemented in 1992-05-20; (confirmed in 2004)

2. Scope of application and non-applicability

• This standard specifies the determination of mechanical impurities in lubricating grease (extraction method).
• This standard is applicable to the determination of the content of substances in lubricating grease that are insoluble in ethanol-benzene mixed liquid and hot distilled water.
• Not applicable: not provided in the available source.

3. Method principle

• Extract the lubricating grease with ethanol-benzene mixed liquid, treat the precipitate on the filter with hot distilled water, and determine the mass of the insoluble residue.

4. Reagents and materials (purity / preparation)

• 3.1 95% Ethanol: analytical grade.
• 3.2 Benzene: analytical grade.
• 3.3 Ethanol-benzene mixed liquid: volume ratio is 1:40.
• Other reagents and materials: not provided in the available source.

5. Apparatus and equipment

• 4.1 Soxhlet extractor: flask with 500 mL.
• 4.2 Support: for placing the glass microporous filter, made of glass or aluminum; the total length of the support must match the length from the extractor to the ground joint.
• 4.3 Porcelain evaporating dish.
• 4.4 Spatula.
• 4.5 Watch glass: diameter 125～175 mm (depending on the diameter of the porcelain evaporating dish).
• 4.6 Beaker: 300～500 mL.
• 4.7 Conical flask: 250～500 mL.
• 4.8 Glass microporous filter: crucible type, pore size 4.5～9 μm (the source source-text extraction is "Ean", requires confirmation against the source standard (source-text extraction)), barium sulfate does not pass through under normal pressure.
• 4.9 Wash bottle: 500～1000 mL, with rubber bulb.
• 4.10 Glass rod: length 150～200 mm, diameter 3～4 mm, both ends fire-polished round.
• 4.11 Water bath or electric heating plate.
• 4.12 Thermostatic oven.

6. Recommended operating conditions

• Thermostatic oven drying temperature: 105～110 ℃.
• During extraction, the rate at which the condensate flows from the condenser into the filter: 3～5 drops per second.
• Extraction time: at least 1.5 h, until the solution in the extractor changes from yellow to colorless.
• Other operating conditions: not provided in the available source.

7. Sampling and specimen preparation

• 5.1 Use a spatula to scrape off the surface layer of the specimen. Then, from at least three places in the specimen not close to the container wall, take approximately equal amounts of specimen into a porcelain evaporating dish, mix carefully, and cover with a watch glass. The total mass of the specimen after mixing shall be not less than 200 g.
• 6.1 Weigh 1.5～2.0 g of specimen into a glass microporous filter, and weigh to the nearest 0.0002 g.

8. Analysis procedure

• 5.2 Preparation of the glass microporous filter: first soak with chromic acid cleaning solution, then wash with distilled water until the filter plate is white. Place the cleaned glass microporous filter in a thermostatic oven at 105～110 ℃ and leave it for 2～3 h, then cool in a desiccator for at least 30 min, and weigh its mass to the nearest 0.0002 g. Repeat the operations of drying, cooling, and weighing until the difference between two consecutive weighings is not greater than 0.0004 g.
• 5.3 Connect the Soxhlet extractor to the flask; this flask is placed on a water bath or electric heating plate, and pour ethanol-benzene mixed liquid into it until the mixed liquid begins to flow from the side tube into the flask, then add a volume of mixed liquid equal to half the volume of the extractor, and pour it into the flask.
• 6.2 Place the filter containing the weighed specimen into the support, then insert the support together with the filter vertically into the extractor, and fill the filter with hot benzene so that the specimen swells better. Then, attach the condenser to the extractor, connect cooling water, check whether all connections of the apparatus are tight and whether it is firmly seated on the support, and then heat.
• 6.3 The heating intensity of the flask shall be such that the rate at which the condensate flows from the condenser into the filter is 3～5 drops per second. The extraction shall continue for at least 1.5 h, until the solution in the extractor changes from yellow to colorless. When the solvent begins to flow from the extractor into the flask, stop heating, then remove the condenser, and carefully take the support and filter out of the extractor. Remove the filter from the support, insert it into a conical flask or place it on a ring, with a beaker underneath, so that the residual solvent flows into the flask or beaker.
• 6.4 After removing the solvent, place the filter on the support, wash first with hot 95% ethanol, then with hot distilled water.
• 6.5 Place the glass microporous filter in a thermostatic oven at 105～110 ℃, leave it at this temperature for 2 h, then cool in a desiccator for at least 30 min, and then weigh to the nearest 0.0002 g. Then place the filter back into the thermostatic oven and leave it for 1 h, cool for 30 min, and weigh. Repeat this operation until the difference between two consecutive weighings is not greater than 0.0004 g.

9. Qualitative and quantitative determination and calculation formula

• The mechanical impurity content in the specimen X [%(m/m)] is calculated according to the following formula:
• The original formula source-text extraction is severely incomplete; only the symbols M1, m2, m3, X can be identified; among them, M1 is the mass of the glass microporous filter and residue, m2 is the mass of the glass microporous filter, and m3 is the specimen mass.
• Complete formula form: requires confirmation against the source standard (source-text extraction).

10. Precision

• Repeatability: the difference between two results of repeated determinations shall not exceed 0.1%(m/m).
• Reproducibility: not provided in the available source.

11. Report

• Take the arithmetic mean of two results of repeated determinations as the mechanical impurity content in the specimen.

12. Referenced documents

• Not provided in the available source.

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 Q&A