GB/T 8022-2019Determination of demulsibility characteristics of lubricating oils (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard replaces GB/T 8022-1987 "Determination of anti-emulsification performance of lubricating oil". This standard is compared with GB/T 8022-1987. The technical changes are as follows.

--- Added introduction;

--- The method is divided into two parts. Method A and Method B. Method A is applicable to samples without extreme pressure agent, and Method B is applicable to Samples with extreme pressure agents (see Chapter 1);

--- Add a chapter on normative references (see Chapter 2);

--- Added the content of the test containing the extreme pressure agent (see Chapter 3, Chapter 7);

--- Modified the preparation temperature of the toluene water saturated solution, the temperature of the centrifuge tube and the temperature during centrifugation (see Chapter 7, Appendix B);

--- Increased the requirements for the calibration of centrifuge tubes (see Chapter 7);

--- Revised the calculation of the percentage of water in the oil (see Chapter 8);

--- GB/T 8022-1987 Appendix A "Extreme Pressure Lubricating Oil Detergency Performance Determination Method" into the standard text, the original GB/T 8022-1987 Appendix B was changed to Appendix A;

--- Increase the preparation of Appendix B toluene water saturated solution.

Introduction

Lubricating oil is susceptible to water contamination during use, and pumping and circulating turbulence may result in the formation of water-in-oil emulsions. This method is for this The determination of the anti-emulsification properties of lubricating oils is instructive.

Caution - Personnel using this standard should have practical experience in formal laboratory work. This standard does not indicate all possible security questions. It is the responsibility of the user to take appropriate safety and health measures and to ensure compliance with the conditions set by the relevant national regulations.

1 Scope

This standard specifies the determination of the anti-emulsification ability of lubricating oil products.

This standard is applicable to the determination of the separation of oil and water from high and medium viscosity lubricants. Method A is suitable for samples that do not contain extreme pressure agents. Method B is suitable for samples containing extreme pressure agents.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this document. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 4756 petroleum liquid manual sampling method

GB/T 6682-2008 Analytical laboratory water specifications and test methods

3 Method summary

3.1 Method A. Add 405mL oil sample and 45mL secondary water in a special separatory funnel, stir at a certain speed at 82 °C 5 min, after standing for 5 h, measure and record the volume of water separated in the oil, the volume of the emulsion and the percentage of water in the oil.

3.2 Method B. Add 360 mL oil sample and 90 mL secondary water to a special separatory funnel and stir at a certain speed at 82 °C 5 min, after standing for 5 h, measure and record the volume of water separated in the oil, the volume of the emulsion and the percentage of water in the oil.

4 Instruments

4.1 Stirrer. The speed meets 4500r/min±500r/min and 2500r/min±250r/min. The detailed structure is shown in Figure 1, Figure 2 and image 3.

Note: Air motors are recommended to avoid spark damage.

4.2 Separating funnel. 500mL, the minimum scale is 5mL; borosilicate heat-resistant glass tube, standard wall thickness, outer diameter of about 54mm, as shown in Figure 4.

4.3 Constant temperature bath. At least two separatory funnels should be immersed, and the constant temperature medium can be immersed in the 500 mL mark line of the separatory funnel. Thermostatic bath Maintain at 82 ° C ± 1 ° C, and can fix the separatory funnel. When mixing oil and water, the vertical centerline of the separatory funnel should be with the agitator The vertical axis coincides.

Note: Silicone oil is not recommended as a constant temperature medium because any contamination into the oil-water mixture can lead to erroneous results.

4.4 Centrifuge. The specific technical requirements are as follows.

a) enable two or more liquid-filled centrifuge tubes to produce 500-800 relative centrifugal force (rcf) at the tip of the centrifuge tube Rotate down.

b) The rotor, trunnion, trunnion cup and cushion of the centrifuge should be tightly coupled to withstand the maximum centrifugal force. Trunnion cup when centrifuged And the buffer should be firmly fixed to the centrifuge tube. In order to reduce the damage caused by broken parts, the centrifuge should be metal with a certain strength.