1、Designation: D 7097 09Standard Test Method forDetermination of Moderately High Temperature PistonDeposits by Thermo-Oxidation Engine Oil Simulation TestTEOST MHT1This standard is issued under the fixed designation D 7097; the number immediately following the designation indicates the year oforiginal
2、 adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the procedure to determine themass of depos
3、it formed on a specially constructed test rodexposed to repetitive passage of 8.5 g of engine oil over the rodin a thin film under oxidative and catalytic conditions at 285C.The range of applicability of the Moderately High TemperatureThermo-Oxidation Engine Test (TEOST MHT2) test method asderived f
4、rom an interlaboratory study is approximately 10 to100 mg. However, experience indicates that deposit valuesfrom 1 to 150 mg or greater may be obtained.1.2 This test method uses a patented instrument, method andpatented, numbered, and registered depositor rods traceable tothe manufacturer3and made s
5、pecifically for the practice andprecision of the test method.41.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3.1 The values stated in SI units are to be regarded asstandard. Although not an SI unit, the special name, litr
6、e (L) isallowed by SI for the cubic decimetre (dm3) and the millilitre(mL) for the SI cubic centimetre (cm3).1.4 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-priate safety
7、 and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:5D 4485 Specification for Performance of Engine OilsD 6335 Test Method for Determination of High Tempera-ture Deposits by Thermo-Oxidation Engine Oil SimulationTest
8、3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 bubble airflow gauge, na precision bore glass tubemarked in tenths of a millilitre used to measure accurately theflow rate of air around and past the depositor rod and tocalibrate mass air flow controllers recommended for use in
9、theprocedure.3.1.2 depositor rod deposits, nparticulate matter formedon the depositor rod surface by oxidation of the thin film ofpassing oil exposed to the rod temperature and air, and weighedafter appropriate washing and drying to obtain the net massgain.3.1.3 filter deposits, nparticulates washed
10、 from the de-positor rod after the test and collected on a special multi-layerfilter cartridge.3.1.4 TEOST2, nan acronym for Thermo-Oxidation En-gine Oil Simulation Test.3.1.5 total rod deposits, nthe mass of deposits collectedon the depositor rod plus any mass of deposits washed from thedepositor r
11、od and later extracted on a filter.3.1.6 volatilized oil, noil vapor coalesced on the mantlewall, and subsequently collected in a vial.3.2 Abbreviations:3.2.1 MHT2, nmoderately high temperature.3.2.1.1 DiscussionThe TEOST MHT procedure evaluatesdeposit formation at temperatures that are closely rela
12、ted tothose of the piston ring zone in reciprocating engines (asdistinguished from the much higher temperatures associatedwith the TEOST 33C, Test Method D 6335, procedure fordetermining potential deposits in turbochargers).1This test method is under the jurisdiction of ASTM Committee D02 onPetroleu
13、m Products and Lubricants and is the direct responsibility of SubcommitteeD02.09.0G on Oxidation Testing of Engine Oils.Current edition approved June 1, 2009. Published July 2009. Originally approvedin 2005. Last previous edition approved in 2006 as D 709706a.2TEOST and MHT are registered trademarks
14、 of the Tannas Co. (Reg. 2001396),Tannas Company, 4800 James Savage Rd., Midland, MI 48642.3The sole source of supply of the apparatus known to the committee at this timeis Tannas Company, 4800 James Savage Rd., Midland, MI 48642. If you are awareof alternative suppliers, please provide this informa
15、tion to ASTM InternationalHeadquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee,1which you may attend.4The TEOST instrument, method and rod are patented. Interested parties areinvited to submit information regarding the identification of an
16、 alternative(s) to thispatented technology to ASTM Headquarters. Your comments will receive carefulconsideration at a meeting of the responsible technical committee,1which you mayattend.5For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceas
17、tm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Summary of Test Method4.1 Deposit-forming tendencies of a
18、n engine oil underoxidative conditions are determined by circulating an oil-catalyst mixture comprising a small sample (8.4 g) of the oiland a very small (0.1 g) amount of an organo-metallic catalyst.This sample mixture is then circulated for exactly 24 h in theTEOST MHT instrument over a special wi
19、re-wound depositorrod heated by electrical current to a controlled temperature of285C at the hottest location on the rod. The depositor rod isweighed before and after the test and any deposit formation onthe rod as well as any deposits collected from rod washings aredetermined. During the test, prec
20、isely controlled and directedair is caused to bathe the oil flowing down the depositor rodand, thereby, to provide opportunity for oxidation. Precision ofthe test is strongly influenced by the care in manufacture of thewire-wound steel depositor rods and the treatment of thecoating of the wound wire
21、, the rate of air flow, and the amountand degree of mixing of the catalyst.5. Significance and Use5.1 The test method is designed to predict the deposit-forming tendencies of engine oil in the piston ring belt andupper piston crown area. Correlation has been shown betweenthe TEOST MHT procedure and
22、the TU3MH Peugeot enginetest in deposit formation. Such deposits formed in the ring-beltarea of a reciprocating engine piston can cause problems withengine operation and longevity. It is one of the required testmethods in Specification D 4485 to define API Category-Identified engine oils.66. Apparat
23、us6.1 TEOST MHT Instrument,3with specific fittings for theMHT procedure including parts and assemblies are as follows:6.1.1 Depositor Rod Casing Assembly:6.1.1.1 Ceramic Isolators, special non-conductive fittingsthat compress the depositor rod O-rings into the end-caps andcenters the depositor rod i
24、n the end-caps to prevent leakage ofoil from the lower end-cap. (See Figs. 4 and 5.)6.1.1.2 Depositor Rod, Wire-Wound, a specially patented,numbered, and registered steel tube wound with pretreatedsteel wire. The steel tube is formed to a selected interiordiameter to precisely contact the surface of
25、 a metal-sheathedthermocouple. The registered depositor rods are required to runthe TEOST MHT procedure. (See Fig. 4, Fig. 5, and Fig. 7.)NOTE 1Precision of the TEOST MHT procedure is highly dependenton the uniformity of manufacture and use of patented and registereddepositor rods. Each depositor ro
26、d is numbered and traceable to themanufacturer and raw steel tubing mill.6.1.1.3 End-cap, Upper, holds the upper end of the glassmantle and depositor rod in place and allows air and oil to enterthe deposit-forming zone separately. (See Fig. 4 and Fig. 7.)6.1.1.4 End-cap, Lower, holds the lower end o
27、f the glassmantle and depositor rod in place and provides an outlet for theoil to pass into the sample flask and subsequently to therecirculating pump inlet tubing. (See Fig. 6.)6.1.1.5 End-cap Nuts, Four, used for compressing smallO-rings around depositor rod and for positioning and sealingthe oil
28、feed tube and sealing the air inlet tubing. (See Fig. 4 andFig. 5.)6.1.1.6 Glass Mantle, the glass casing that surrounds thedepositor rod and diverts volatilized oil into a collecting vial.(See Figs. 4-6.)6.1.1.7 Mantis Clip, a wire-spring device holding thesample flask in place on the lower end-cap
29、. (See Fig. 2 and Fig.6.)6.1.1.8 Oil Feed Tube, the avenue for oil to be deliveredfrom the pump to the top of the depositor rod.6.1.1.9 End cap O-rings, Large, Petroleum-resistant, createa seal between the end-caps and glass mantle. (See Fig. 5.)6.1.1.10 End cap O-rings, Small, Petroleum- and Heat-r
30、esistant, creates an air and fluid seal between depositor rodand end-caps. (See Fig. 5.)6.1.1.11 Pump Outlet Tubing, a flexible transparent vinyltube of 3.2 mm outer diameter with a flared end used totransport the oil sample from the oil pump to the oil feed tube.(See Fig. 6.)6.1.1.12 Sample Flask,
31、a small (25 mL), modified form ofan Erlenmeyer flask with sidearm into which the catalyst andsample are first weighed, then later used to feed the sample tothe circulating system. (See Fig. 2 and Fig. 6.)6.1.1.13 Stainless Steel Hex Screws and Busbar End Piece,these secure the depositor rod to the b
32、usbars.6.1.1.14 Thermocouples, Two, stainless steel sheathed, 1.57mm diameter by 150 mm length. One, a J-type, is used forcontrolling the test temperature (depositor rod) while the other,a K-type, is used to protect against an over-temperaturecondition.6.1.1.15 Thermocouple Locking Collar, a fitting
33、 that can betightened on the thermocouple to ensure the thermocouple tipis at the correct position when placed inside the depositor rod.(See Fig. 4.)6.1.1.16 Volatiles Vial Clip, the device that holds the vola-tiles collection vial in place on the mantle. (See Fig. 4.)6.1.2 Airflow Control Assembly,
34、 sets air flow at chosen flowrate.6.1.2.1 Bubble Airflow Gauge, a device for precisely estab-lishing the airflow rate and calibrating the flow meter from 1 to30 mL/min. (See Fig. 1.)6.1.2.2 Calibrated Flow Meter, capable of measuring ap-proximately 1 to 20 mL/min of air and providing a continuousrea
35、ding on airflow rate when calibrated.6.1.2.3 Handheld Digital Flow Meter, an optional device tomonitor air flow to or out of the mantle, capable of reading aflow rate of 10.0 6 0.1 mL/min of air.6.1.2.4 Precision Digital Mass Flow Controller, an optionaldevice that allows the precise control of the
36、input air flow. (SeeFig. 1a.)6.1.2.5 Stopwatch, reading to 1/100 s.6.1.3 Filtering Flask Assembly, provides the means forfiltering particles washed from the depositor rod. (See Fig. 8.)6Selby, T. W., and Florkowski, D. F., “The Development of the TEOST ProtocolMHT Bench Test of Engine Oil Piston Dep
37、osit Tendency,” Supplement to theProceedings of the 12th Esslingen Colloquium, Esslingen, Germany, January 11-13,2000, pp. 55-62.D70970926.1.3.1 Filter Cartridge, a special multilayer filter made forthe TEOST MHT procedure fitting the end of the filter funnelalso made for the TEOST procedure. (See F
38、ig. 8.)6.1.3.2 Filter Funnel, a special combination funnel of400-mL capacity, necking down to a 10-mL graduated ornon-graduated section that, in turn, ends in a glass or Luer-locktip fitting the special filter cartridge used in the procedure. (SeeFig. 8.)6.1.3.3 Filter Tube Assembly, a metal or poly
39、ethylene tubeinserted through a No. 8 rubber stopper in the vacuum flask tofit the lower outlet of the filter cartridge. (See Fig. 8.)6.1.3.4 Vacuum Flask, 1000-mL capacity for collecting thehydrocarbon solvent and oil during the filter rinse.6.1.3.5 Vacuum Source, a vacuum source sufficient to draw
40、the hydrocarbon solvent and oil through the filter and providethe necessary filter drying.FIG. 1 Bubble GaugeD70970936.1.3.6 Wire Rod, stainless steel, 1 to 1.5 mm diameter, 300to 350 mm length, for dislodging any deposits trapped in thenarrow portion of the filter funnel just above the filter.6.2 A
41、ncillary Equipment, needed or helpful:6.2.1 Balance, capable of weighing deposits to the nearest0.1 mg with a minimum capacity of 100 g.6.2.2 Catalyst Syringe, a syringe of 100 L capacity, forcarefully metering the catalyst being weighed into the sampleflask.6.2.3 Oil Sample Transfer Pipettes, dispo
42、sable glass orplastic pipettes or droppers.6.2.4 Oil Extraction Test Tubes, three, 120-mm tall, made ofglass or hydrocarbon solvent-resistant plastic.6.2.5 Temperature Recorder, an optional device for trackingthe temperature of the upper depositor rod thermocouple overthe 24-h period of the test.6.2
43、.6 Thermocouple Depth Insertion Gauge, an optionalmeasurement device fabricated for simple setting and checkingof the thermocouple insertion depth, using a millimetre gradu-ation scale.6.2.7 Vials and Caps, a vial and matching cap of 10 mL ormore in volume with an 11.5 mm diameter mouth and an outer
44、diameter of 20 mm to collect the volatile material emitted bythe oil and collected on the mantle wall during the test as wellas the recovered, end-of-test oil sample. (See Fig. 4.)6.2.8 Weighing Boat, a light, circular or oblong weighingcontainer, preferably made of aluminum with a diameter orlength
45、 of 7 to 10 cm and notched in two diametrically opposedplaces to prevent the rod from rolling. (See Fig. 3.)6.2.9 Air-Flow Restrictora small PTFE washer designedto limit the amount of air allowed to pass between the sampleflask and the drain on the lower end-cap.7. Reagents and Materials7.1 Abrasive
46、 Paper, 800-grit emery (aluminum oxide).7.2 Acetone, particle-free, reagent grade, for final cleaningof new depositor rods. (WarningFlammable. Health haz-ard.)7.3 Air, oil-free, clean, and dry, obtained from cylinder gasor house line, regulated to 15 to 100 kPa (2 to 15 psi) at morethan 690 kPa (100
47、 psi).7.4 Cyclohexane or Other Alkane Hydrocarbon Solvent ofEquivalent Volatility, reagent grade. (WarningFlammable.)Do not use naphthenic or aromatic hydrocarbons. Throughoutthe test, this solvent is referred to as “hydrocarbon solvent.”7.4.1 DiscussionThe volatility of the alkane hydrocarbonsolven
48、t ensures timely evaporation of the deposits on the rodand filter.7.5 Catalyst3Catalyst contains iron, lead, and tin in ratioschosen for emulating engine deposit conditions.7.5.1 DiscussionFor long term storage, it is acceptable torefrigerate the catalyst until a few hours before use (let catalystwa
49、rm to room temperature before opening to eliminate con-densation). Temporary unopened storage, up to four weeks,may be at room temperature.7.6 Certified Reference Oils,3certified low deposit fluid(LDF, about 10 to 15 mg), medium deposit fluid (MDF, about40 to 50 mg), and high deposit fluid (HDF, about 70 to 90 mg).7.7 Combination Pump Calibration and Temperature Con-trol Thermocouple Depth Setting Oil, TPC-1,3a highlydeposit-resistant oil used in setting pump calibration andtemperature control calibration without forming significantdeposits on the depositor rod d
