1、Designation: D 5763 95 (Reapproved 2006)An American National StandardStandard Test Method forOxidation and Thermal Stability Characteristics of Gear OilsUsing Universal Glassware1This standard is issued under the fixed designation D 5763; the number immediately following the designation indicates th
2、e year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the
3、oxida-tion characteristics of extreme pressure and non-extreme pres-sure gear oils and includes the quantitative determination oftotal sludge, viscosity change, and oil loss.NOTE 1While the round-robin tests used ISO VG 220 extremepressure gear oils for developing precision data, the test method can
4、 beextended to other viscosity grades and to non-extreme pressure gear oils.Refer to Classification D 2422 for viscosity grades.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not purport to address a
5、ll of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 445 Test Method f
6、or Kinematic Viscosity of Transparentand Opaque Liquids (and Calculation of Dynamic Viscos-ity)D 2422 Classification of Industrial Fluid Lubricants byViscosity SystemD 2893 Test Methods for Oxidation Characteristics ofExtreme-Pressure Lubrication OilsD 4057 Practice for Manual Sampling of Petroleum
7、andPetroleum ProductsD 4871 Guide for Universal Oxidation/Thermal StabilityTest ApparatusE1 Specification for ASTM Liquid-in-Glass Thermometers3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 adherent sludge, nsludge that is formed on the wallsof a container and is not easily r
8、emoved.3.1.2 aliquot, nportion of sample being tested that is arepresentative portion of the whole.3.1.3 extreme pressure gear oil, ngear oil that containschemical additives, such as sulfur and phosphorus compounds,which produce a protective film on the metal surface to provideanti-scuffing and anti
9、-scoring properties.3.1.4 filterable sludge, nsludge that is formed in the oil.3.1.5 non-extreme pressure gear oil, n, ngear oil thatcontains no extreme pressure additives.3.1.6 oxidation, nthe process by which oxygen chemi-cally reacts with materials.3.1.7 sludge, nin gear oils, a precipitate that
10、sometimesforms as the oil ages or oxidizes.3.1.8 universal glassware, nthe glassware that is de-scribed in the universal oxidation thermal stability test. Referto Guide D 4871.4. Summary of Test Method4.1 The viscosity of the gear oil being tested is determined.A100-g aliquot of the oil in a weighed
11、 apparatus is subjected toa temperature of 120C for 312 h while dry air is passedthrough the aliquot at 3 L/h.4.2 At the end of the stress period, the aliquot is cooled toroom temperature. The apparatus is reweighed to determine oilloss. Filterable sludge is recovered by vacum filtration using a2.8-
12、m glass fiber filter medium. The viscosity of the filteredoil is determined. Sludge adhering to the oxidation cell andassociated glassware is rinsed with heptane and the washingspassed through the same filter used to filter the filterablesludge. The filter is dried in an oven to a constant weight to
13、determine the total filterable sludge.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.09.0D on Oxidation of Lubricants.Current edition approved Nov. 1, 2006. Published January 2007. Originallyap
14、proved in 1995. Last previous edition approved in 2001 as D 5763 95 (2001).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe
15、 ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.3 The apparatus is dried and weighed to determine theamount of adherent sludge. The sum of the filterable sludge andadherent sludge is reported as total sludge. The perc
16、entagechange in viscosity and percent oil loss are also reported.5. Significance and Use5.1 Degradation of gear oils by oxidation or thermal break-down, or both, can result in sludge buildup and render the oilunsuitable for further use as a lubricant.5.2 This is the only test method that employs gla
17、ssware tomeasure the amount of sludge produced during oxidation andthermal degradation. This test method is a modification of TestMethod D 2893 which measures the viscosity increase andprecipitation number of the oil stressed at 95C, but does notmeasure the amount of sludge formed.5.3 This test meth
18、od can be used to evaluate the oxidation/thermal stability of gear oils. However, the test results may notcorrelate with the performance of gear oils in field service.6. Apparatus6.1 Heating Bath or Block,3thermostatically controlled,capable of maintaining the oil sample in the oxidation cell at aun
19、iform temperature of 120 6 1C and large enough to hold aminimum of two oxidation cells and sufficiently deep to allowapproximately 120 mm of the test tubes to extend above theheating liquid or block. The heating block is further describedin Test Method D 4871.6.2 Oxidation Cell,3consists of borosili
20、cate glass; a 38- mminside diameter and a 300 6 5-mm length is required.NOTE 2While the round-robin test used the oxidation cell from aspecific equipment manufacturer in determining the precision statement,the test method permits the use of other oxidation cells that meet therequirements of 6.2.6.3
21、Air Delivery Tube,3a borosilicate glass tube having aninside diameter of 5 mm and a minimum length of 320 mm,with the lower tip cut at a 45 angle.NOTE 3The oxidation cell and delivery tube are further described inTest Method D 4871.6.4 Flowmeters,3one for each oxidation cell, capable ofmeasuring an
22、air flow of 3 L/h6 0.5 L/h.6.5 Air DryerBefore being supplied to the flowmeters, theair shall be passed through a drying tower packed withindicating grade anhydrous calcium sulfate or equivalent. Thequantity of desiccant should be sufficient to last for the entiretest. It is recommended that the dry
23、ing tower be filled withfresh desiccant prior to the test.6.6 Filter, glass fiber, 2.8-m porosity, 47 mm in diameter.6.7 Balance, electronic, top-loading, capable of weighing tothe nearest centigram (0.01 g) and having the capacity to weighup to 2000 g.6.8 Filter Holder, 47 mm, consisting of a boros
24、ilicate glassfunnel and a funnel base with a coarse-grade fritted glass filtersupport or stainless steel screen support such that the filter canbe clamped between the ground glass sealing surfaces of thefunnel and its base by means of a metal clamp.6.9 Oven, explosive-proof, capable of heating from
25、50 to60C and of a sufficient size to hold oxidation cells.6.10 Thermometer, ASTM solvent distillation thermometerhaving a range from 98 to 152C and conforming to therequirement for Thermometer 41C in accordance with Speci-fication E1.6.11 Vacuum Source, to provide pressure reduction to 100 65 mm Hg
26、absolute pressure.7. Reagents and Materials7.1 Air Supply, dried air, oil free, at constant pressure topermit 3 L/h air flow through the system. House air supply orpressurized air cylinders can be used.7.2 Calcium Sulfate Desiccant,Anhydrous, indicating grade(desiccant that changes color when it nea
27、rs saturation withwater). Desiccants equivalent to calcium sulfate can be used.7.3 Heptane, minimum purity99.75 %. (WarningHeptane is flammable and a health hazard.)8. Sampling8.1 Samples for this test method can come from tanks,drums, small containers, or operating equipment. Therefore,use the appl
28、icable apparatus and techniques described inPractice D 4057 to obtain suitable samples.8.2 Special precautions to preserve the integrity of a samplewill not normally be required. It is good practice to avoidundue exposure of samples to heat, sunlight, or strong directlight. Visibly heterogeneous sam
29、ples should not be used.8.3 It is recommended that a 200-mL representative beobtained. To ensure the aliquot being tested is representative ofthe sample, agitation; for example, stirring or shaking of the oilprior to obtaining an aliquot, is recommended.9. Preparation of Apparatus9.1 Cleaning Glassw
30、are:9.1.1 Clean new glassware by washing with a hot detergentsolution (using a bristle brush) and rinse thoroughly with tapwater. When any visible deposits remain, soaking with a hotdetergent solution can be helpful. After final cleaning bysoaking with a suitable cleaning solution rinse thoroughly w
31、ithtap water and then distilled water, and allow to dry at roomtemperature or in an oven.9.1.2 Used glassware should be cleaned immediately fol-lowing the end of a test. When additional cleaning is necessary,use a non-chromic acid containing cleaning solution.9.2 Heating Block or BathEnsure that the
32、 heating blockor bath is able to heat the oxidation cell at the controltemperature of 120C.9.3 FlowmeterEnsure that the flowmeter is capable ofdelivering the desired flow rate of 3.0 L of air per hour.10. Procedure10.1 Using Test Method D 445, determine the viscosity ofthe oil at 100C. Record as V2.
33、3The sole source of supply of the apparatus (universal glassware and heatingbath with flowmeters as a complete unit) known to the committee at this time isFalex Corp., 1020 Airpark Drive, Sugar Grove, IL 60554. If you are aware ofalternative suppliers, please provide this information to ASTM Interna
34、tionalHeadquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee,1which you may attend.D 5763 95 (2006)210.2 Adjust the heating bath or block to a temperature highenough to maintain the oil in the desired number of oxidationcells at the required
35、 temperature of 120 6 1C.10.3 Place and weigh a 1000-mL beaker on the balance.Zero the tare of the beaker and place the oxidation cell in thebeaker. Insert the air delivery tube in the cell. The angled tip ofthe air delivery tube should rest on the bottom of the oxidationcell. Obtain the weight of t
36、he cell and delivery tube. Record asB1.10.4 Slowly pour 100.00 6 0.1 g of oil sample into theoxidation cell which contains the air delivery tube. Obtain theweight of the oil sample, air delivery tube, and oxidation cell,A2.10.5 Place the oxidation cell containing the oil sample andair delivery tube
37、in the heating block or bath.10.6 Connect the air delivery tube to the air source from theflowmeter. Adjust the flow of dried air to 3 6 0.5 L/h.10.7 Monitor the temperature of the oil sample and adjustthe heating block/bath thermostat, if necessary. Observe thetemperature of the oil sample twice du
38、ring the first hour, thenonce every hour for at least 3 h, making the necessaryadjustment each time until a constant temperature of 120 61C is read twice in succession. Check the air flow andtemperature at least twice a day and adjust the control flow,when necessary.10.8 At the end of 312 h (13 days
39、), remove the oxidationcell containing the oxidized oil and delivery tube from the bathor block, and allow the oxidized oil to cool to room tempera-ture. When an oil bath is used, rinse the outside of the oxidationcell with heptane and wipe dry. Place the cell and its contentsin a tared 1000-mL beak
40、er and obtain the weight of the oilsample, oxidation cell, and delivery tube as in 10.4. Record thisweight, A1.10.9 Weigh a 2.8-m glass fiber filter to the nearest 0.01 gand record, F1. Using the filter holder apparatus, vacuum filterthe cooled oxidized oil through the glass filter. Determine thevis
41、cosity at 100C of the filtered oil by Test Method D 445.Record the viscosity result, V1.NOTE 4The viscosity and sludge determinations for the oxidized oilshould be done within four days after removing the cell from the heatingbath or block. It has been found that extending storage time beyond fourda
42、ys can give variable test results.10.10 Wash the oxidation cell and air delivery tube withheptane and filter the washings through the same filter. Con-tinue washing until the heptane is no longer colored by theoxidized oil. Draw air through the filter until the precipitateappears dry. Place the filt
43、er in an operating hood for 0.5 h toevaporate heptane. Transfer the filter to a 50 to 60C explosive-proof oven for 0.5 h. Let cool to room temperature and weigh,F2.10.11 Allow heptane to evaporate from the oxidation celland then place the cell in an explosive-proof oven at 50 to 60Cfor 1 to 2 h. Dry
44、 the air delivery tube by passing air through thetube. Let the oxidation cell cool to room temperature. Weighthe oxidation cell and air delivery tube, B2.11. Calculations11.1 Determine the amount of sludge, viscosity change, andoil loss by the following equations.11.1.1 Filterable sludge on filter,
45、g.D25 F2 F1(1)where:D2= amount of sludge on filter pad, g,F2= weight of filter pad and sludge, g, andF1= weight of filter, g.11.1.2 Adherent sludge on oxidation cell and air deliverytube, g.D15 B2 B1(2)where:D1= amount of sludge on oxidation cell and air deliverytube, g,B2= weight of oxidation cell
46、and air delivery tube, solventwashed and dried, g, andB1= original weight of oxidation cell and air delivery tube,g.11.1.3 Total sludge, g.D35 D11 D2(3)where:D3= total amount of sludge, g.11.1.4 Viscosity at 100C increase, mm2,%V35V1 V2V23 100 (4)where:V3= viscosity increase, %,V2= original viscosit
47、y of oil sample, andV1= viscosity of oxidized oil sample.11.1.5 Oil loss, g.C35 A2 A1(5)where:C3= oil loss, g,A2= original combined weight of oil sample, oxidationcell, and air delivery tube, g, andA1= combined weight of oxidized oil, oxidation cell, andair delivery tube, g.12. Report12.1 Report the
48、 amount of filterable sludge on the filter tothe nearest 0.01 g.12.2 Report the amount of adherent sludge on the oxidationtubes to the nearest 0.01 g.12.3 Report the total amount of sludge to the nearest 0.01 gor to the nearest 0.01 %.12.4 Report the viscosity increase in percent.D 5763 95 (2006)312
49、.5 Report oil loss to the nearest 0.01 g or percent.13. Precision and Bias413.1 PrecisionThe precision of this test method as deter-mined by the statistical examination of the inter-laboratory testresults is as follows.13.1.1 Total Sludge:13.1.1.1 RepeatabilityThe difference between successiveresults obtained by the same operator with the same apparatusunder constant operating conditions on identical test materialswould in the long run, in the normal and correct operation ofthe test method, exceed the following values only in one casein twent
