1、Designation: D 2070 91 (Reapproved 2006)An American National StandardStandard Test Method forThermal Stability of Hydraulic Oils1This standard is issued under the fixed designation D 2070; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revi
2、sion, 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 method2is designed primarily to evaluate thethermal stability of hydrocarbon based hydrau
3、lic oils althoughoxidation may occur during the test.1.2 The values stated in SI units are to be regarded as thestandard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-p
4、riate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D 4057 Practice for Manual Sampling of Petroleum andPetroleum Products2.2 Copper Development Association Standard4UNS C11000 Electrolytic Tough Pitch C
5、opper2.3 American Iron and Steel Institute Standard (AISI)5W-1 Carbon Tool Steel3. Summary of Test Method3.1 A beaker containing test oil, copper and iron rods isplaced in an aluminum block in an electric gravity convectionoven for 168 h at a test temperature of 135C. At thecompletion of the test, t
6、he copper and steel rods are ratedvisually for discoloration and the oil is analyzed for thequantity of sludge.4. Significance and Use4.1 Thermal stability characterizes physical and chemicalproperty changes which may adversely affect an oils lubricat-ing performance. This test method evaluates the
7、thermalstability of a hydraulic oil in the presence of copper and steelat 135C. Rod colors are the evaluation criteria. Sludge valuesare reported for informational purposes. No correlation of thetest to field service has been made.5. Apparatus5.1 An aluminum block with equally spaced holes is used.A
8、n example is described in Fig. A1.1 of Annex A1.5.2 Electric gravity convection oven capable of maintainingthe aluminum block at a test temperature of 135C 6 1C.5.2.1 Calibrated thermocouple and temperature indicatorcentered in aluminum block.5.3 250 mL Griffin beakers of borosilicate glass.5.4 Copp
9、er test specimens are to be UNS C11000, 99.9 %pure electrolytic tough pitch copper, 6.35 mm in diameter by7.6 cm in length (0.25 in. by 3.0 in.).5.5 Steel test specimens are to be AISI W-1 1 % carbonsteel, 6.35 mm in diameter 7.6 cm in length (0.25 by 3.0 in.).5.6 Silicon carbide abrasive 320 grit w
10、ith cloth backing.5.7 Crocus cloth.5.8 No. 41 Whatman filter paper,647 mm diameter.5.9 Millipore filter,78 micron Type SC, 47 mm diameter.5.10 Millipore glass filter holder, 47 mm, Cat #XX10.04700or equivalent.5.11 Cincinnati Milacron color chart.85.12 25 mL pipette.6. Reagents6.1 Reagent Grade Hept
11、ane(WarningFlammable.Health hazard.)6.2 Reagent Grade Acetone(WarningFlammable.Health hazard.)1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.N0.08 on Thermal Stability.Current edition approved
12、Nov. 1, 2006. Published December 2006. Originallyapproved in 1991. Last previous edition approved in 2001 as D 2070 91 (2001).2This procedure was adopted from the Cincinnati Milacron Thermal StabilityTest, Cincinnati Milacron Manual 10-SP-89050.3For referenced ASTM standards, visit the ASTM website,
13、 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 ASTM website.4Available from Copper Development Assoc., 2 Greenwich Office Park, Box1840, Greenwich, CT 06836.5Available from Ame
14、rican Iron and Steel Institute (AISI), 1140 ConnecticutAve., NW, Suite 705, Washington, DC 20036, http:/www.steel.org.6Whatman Int. Ltd., Maidstone, England.7Millipore Filter Corp., Bedford, MA.8Cincinnati Milacron, 4701 Marburg Ave., Dept 97B Lubricants and Tribology,Cincinnati, Ohio, 45209, 513-84
15、1-8660.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7. Preparation of Apparatus7.1 Handle the rods at all times using forceps or clean cottongloves.7.2 Catalyst preparationClean the iron and copper cata-lyst rods, whether new or p
16、reviously used, prior to use. Cleanthe rods with the 320 silicon carbide abrasive cloth whilerotating the rods in a drill chuck at 1700 to 1800 r/min. Cleanthe surface until it has a bright copper or steel appearance.Discard rods when diameter is less than 6.2 mm.7.3 Prepare surface finally with a c
17、rocus cloth. Remove allgrind marks. Finish the rods to a lightly polished surface finish.7.4 Wash the rods individually with acetone and air dry oncompletion of the polishing operation.8. Procedure8.1 Place a representative 200-mL sample of test oil ob-tained per D 4057 sampling procedure in a clean
18、 250-mLGriffin beaker containing one each of the cleaned and polishediron and copper rods.8.2 Place the rods totally below the surface of the oil andcrossed. Place them in contact with each other at one pointonly.8.3 Place the beaker and its contents in the pre-heatedaluminum block test fixture in t
19、he oven.8.4 Maintain the test fixture at 135 6 1C for 168 h. Startthe time when the test sample is placed in the oven.8.5 Keep the oven doors closed during the entire test period.Monitor the temperature continuously via thermocouple in thecenter of the test block.8.6 At the completion of 168 h, remo
20、ve the beakers from theoven and allow to cool to room temperature before proceeding.Individually remove the rods from the oil sample. Remove anyloose sludge clinging to the rods with a plastic or rubberpoliceman and return the sludge to the oil.8.7 Copper Rod AnalysisWash the rod with heptane toremo
21、ve all oil and allow to air dry. Discard the heptane wash.Make a visual evaluation of the condition of the rod against theCincinnati Milacron color chart (available from CincinnatiMilacron7) and record.8.8 Steel Rod AnalysisWash the steel rod with heptane toremove all oil and allow to air dry. Disca
22、rd the heptane wash.Make a visual evaluation of the rod against the CincinnatiMilacron color chart and record.8.9 For each sample, dry a #41 Whatman filter for1hinanoven at 70C and cool in a dessicator. Weigh to the nearest 0.1mg. Vacuum filter at a nominal 200 mm of Hg vacuum oilthrough the pre-wei
23、ghed #41 Whatman filter. Do not rinse thebeaker at this time. Remove the oil filtrate and set aside.Replace the filter flask with a clean one and wash all remainingresidue from the beaker with heptane. Wash the residue on thefilter paper with heptane until all evidence of oil is removed.Oven dry the
24、 residue and filter paper at 70C, 1 h, allow to cooland weigh to nearest 0.1 mg. For each sample pre-weigh an 8micron Millipore filter pad to the nearest 0.1 mg. From the oilfiltrate, pipet 25 mL of oil and vacuum filter at a nominal 200mm of Hg vacuum through the pre-weighed 8 micron Milliporefilte
25、r pad. Wash residue with heptane, air dry, and weigh to thenearest 0.1 mg.9. Calculation9.1 Total Sludge DeterminationThe weight of the sludgeon the No. 41 Whatman paper is reported as milligrams per 100mL of oil. Therefore, the weight of the original filter paper issubtracted from the dried filter
26、paper plus residue and thedifference divided by two. The weight of the sludge on the 8micron Millipore filter pad is also reported as milligrams per100 mL. The weight of the original filter pad is subtracted fromthe weight of the dried residue plus filter pad and the differencemultiplied by four. To
27、tal sludge is the summation of the sludgefrom the No. 41 Whatman filter paper plus the sludge from the8 micron filter pad. Weight of total sludge (mg/100 mL of oil)T 2 W 3 0.5 1 M 3 4 (1)where:W = weight of sludge on Whatman filter in mgM = weight of sludge on 8 micrometer millipore filter inmgT = t
28、otal weight of sludge in mg/100 mL10. Report10.1 Report the color of the copper and steel rods aspreviously determined.10.2 Report the total sludge in mg/100 mL oil.11. Precision and Bias11.1 The precision of this test method was determined by astatistical analysis of interlaboratory test results. T
29、he followingcriteria should be used for judging the acceptability of data.11.2 RepeatabilityThe difference between successive testresults obtained by the same operator with the same apparatusunder constant operating conditions on identical test material,would in the long run, in the normal and corre
30、ct operation ofthe test method, exceed the following values only in one casein twenty:Copper rod color 1 unitSteel rod color 1 unitTotal sludge 1.04 (X +1)where X denotes mean value.11.3 ReproducibilityThe difference between two singleand independent results obtained by different operators work-ing
31、in different laboratories on identical test material would, inthe long run, exceed the following values only in one case intwenty:Copper rod color 4 unitsSteel rod color 2 unitsTotal sludge 3.25 (X +1)where X denotes mean value.11.4 BiasSince there is no accepted reference materialsuitable for deter
32、mining the bias for the procedure, bias has notbeen determined.12. Keywords12.1 thermal stability; hydraulic oils; oil sludging; coppercorrosion; steel corrosion; Cincinnati Milacron; heat testD 2070 91 (2006)2ANNEXA1. ALUMINUM TEST FIXTUREFIG. A1.1 Aluminum Test Fixturein. mmA Overall diameter 12.0
33、0 304.8B Thickness 5.500 139.7C Edge thickness 0.7500 19.05D Recess diameter 10.50 266.7E Recess depth 1.750 44.45F Diameter of hole 3.000 76.20G Depth of hole 2.750 69.85H Distance from center to hole center 3.500 88.90D 2070 91 (2006)3ASTM International takes no position respecting the validity of
34、 any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to
35、revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Y
36、our comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is co
37、pyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 2070 91 (2006)4
