1. LUBRICATING OILS CRITICAL TEST PARAMETER OF LUBRICATING OIL LIKE ENGINE OILS, GEAR OILS, HYDRAULIC OILS, MACHINARY OILS ETC. SNCRITICAL TESTPART SPECTION 1Visual ExaminationVisual examination 2 Kinematic Viscosity @ 100 °C IS:1448: P:25/ASTM D445 3 Kinematic Viscosity @ 40 ° C IS:1448: P:25/ASTM D445 4Viscosity IndexIS:1448 P:56/ ASTM D 2270 5Pour PointIS:1448 P:10 6Sulphated ash % by massIS:1448 P:4 7Flash Point COC and PMCCIS:1448 P:69/ P:21 8Copper Strips CorrosionIS:1448 P:15 9 Aniline PointIS:1448 P:3 10TANIS:1448 P:1 D664 11 TBNIS:1448 P:86 D2896 12SAP valueIS:1448 P:55 13Emulsion characteristicIS:1448 P:91 14ERBP Annexure – ‘A’ of IS :8654 : 2001(Second Revision) RA -2011 15Rust preventiveIS:1448 P:96 16TEAJSS: 9150-11 : 2009 17Oleic AcidJSS: 9150-11 : 2009 18PH of aqueous extractsJSS: 9150-11 : 2009 19 Presence of Ca, Ba, Zn, S, P etc.. ICP, CHN,GC,XRF,AAS, UV, FTIR

2. VISUAL EXAMINATION APPEARANCE./ COLOUR: METHOD ASTM D 1500 / IS 1448 P:12, IP 196 Appearance gives visual indication of product clarity. As far as possible the oil should appear clean and without suspended particles and globules to the naked eye. Colour of the product is no indication of the quality of the product. Generally oils become black during service. Same batch of oil should have same colour in fresh oil. Same brand may have slightly different colour. if they are of different batches. Some time, colours are added just for fancy like engine oils are modern.

3. KINEMATIC VISCOSITY @ 100 0 C & 40 0 C Viscosity is most important characteristic for lubrication For engine oil/gear oil/brake fluid etc.. it will be at 100 o C & for industrial lubes it is at 40 0 C. During service, lubricants thicken due to oxidation, nitration, sulfonation, soot loadings, deposits, polymerization, insoluble, waxes, high viscosity fuel dilution additive separation additive disintegration etc. Low viscosity fuel dilution reduces viscosity. Change in viscosity affects lubrication. Lower viscosity results in lubrication failure. Higher viscosity results in additional and significant power consumption. UNIT: kv= T x C

4. VISCOSITY INDEX VISCOSITY INDEX METHOD ASTM D 2270/ IS 1448 P: 56, IP 226 Viscosity Index indicates temperature viscosity behavior of the oil with reference to the behavior of the two reference oils. Higher the viscosity index, lower will be change in viscosity with respect to temperature.

5. POUR POINT Lowest temperature at which the fluid will flow Indicates lowest operating temperature Measured in °C. It indicates low temperature flow property of the fluid. The hydrocarbons of wax type dissolved in the oils crystalize and precipitate at lower temperature affecting flow property. This has significance in low temperature regions when the system is kept off for few hours and restarted in the morning. It is also important in refrigeration systems. The pour point can be suppressed by additives. But this does not prevent wax precipitation-it only avoids their agglomeration or forming mat like network. Hence pour point depressants are not used in refrigeration oils.

6. Flash Point COC and PMCC FLASH POINT (COC)/PMCC METHOD ASTMD92/D93 IS1448 P:69, IP36 Note: PMCC method only to be use for engine oils in service since fuel contaminate ions suspected. For other oils including new engine oils only COC method to be used. Flashpoint (by PMCC ASTM D93Method) gives indication of fuel dilution since fuels have lower flash point than the engine oils. It may also indicate contamination/cracking of the oil.

7. COPPER STRIPS CORROSION 2,3 HRS AT 100 °C To evaluate the degree to which a lubricant will corrode copper-containing materials ie bronze, brass SIGNIFICANCE: This test help to determine the suitability Of a lubricant for use in equipment containing copper- based components. It may also be used with silver bearing metals.

8. Aniline Point : Aniline point is the lowest temperature at which aniline and a solvent (gasoline) are completely miscible & which serve as an indication of the type of hydrocarbons present in the solvent the content of the aromatic being higher According as the temperature is lower. Aniline also called phenyl amine Total Acid Number (TAN)

9. TOTAL ACID NUMBER (TAN) The Total Acid Number (TAN) is a measurement of Acidity that is determined by the amount of potassium hydroxide in mg that is needed to Neutralize the acids in one gram of oils. TAN value may also be useful in s to determine oxidation and the subsequent corrosion risk in machinery.

10. TOTAL BASE NUMBER (TBN) TOTAL BASE NUMBER (TBN) METHOD ASTM D 2896/ IS 1448 P: 86, IP 276 TBN is measurement of basicity that is expressed in terms of the equivalent no of mg of KOH per gram of oil (mg KOH/g) TBN generally range from 6-80 mg KOH/g in modern lubricant 7-10 mg KOH/g in general Automotive 10-15 mg KOH/g in Diesel Operation and TBN is typically higher for marine grade lubricant. It Indicates alkalinity of the engine oil to combat the effects of acids produced due to combustion of fuels. Fuels contain Hydrogen, Carbon, and small quantity of Sulphur. Air contains Nitrogen and Oxygen. The combustion of fuel produces oxides of Carbon, Sulphur, Nitrogen and Hydrogen which are acidic and corrosive particularly when they combine with water. Engine Oil has to neutralize the acids thus possibly coming in contact with the engines surfaces. Hence alkalinity is provided and is measured as TBN-mg of KOH equivalent per gram of engine oil.

11. Emulsion characteristic Emulsion is a mixture of two or more liquids that are normally immiscible Two liquid can form different type of emulsions Oil and water can form. i- oil in water emulsion Wherein the oil is dispersed phase & water is the dispersion medium ii- water in oil emulsion wherein water is the dispersed phase oil is the dispersion medium

12. SAPONIFICATION VALUE, SAP) Saponification value represent the number of mg of KOH required to saponify 1 gm of fat under the condition specified to Measure all the fatty acid present Exmp : soap are sodium or potassium salt of long chain Fatty acids. When triglycerides in fat/ oil react with aqueous NaOH, they are converted into soap and Glycerol. This is called alkaline hydrolysis of esters. Since this reaction leads to formation of soap, it is called saponification process In simple term:- saponification is the name for chemical reaction between an acid and a base to form a salt.