1、Designation: D3829 17D3829 18Standard Test Method forPredicting the Borderline Pumping Temperature of EngineOil1This standard is issued under the fixed designation D3829; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、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. Scope*1.1 This test method covers the prediction of the borderline pumping temperature (BPT) of engine oils through the use of
3、a 16 hcooling cycle over the temperature range from 0 C to 40 C. The precision is stated for temperatures from 34 C to 15 C.1.2 Applicability to petroleum products other than engine oils has not been determined.1.3 The values stated in SI units are to be regarded as standard. No other units of measu
4、rement are included in this standard.1.3.1 ExceptionThis test method uses the SI based unit of milliPascal second (mPas) for viscosity, which is equivalent tocentipoise (cP).1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsib
5、ilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standard
6、izationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:E563 Practice for Preparation and Use of an Ice-Poin
7、t Bath as a Reference TemperatureE644 Test Methods for Testing Industrial Resistance ThermometersE1137 Specification for Industrial Platinum Resistance ThermometersE2877 Guide for Digital Contact Thermometers2.2 ISO Standards:2ISO 17025 General Requirementsrequirements for the Competencecompetence o
8、f Testingtesting and Calibration Laboratories-calibration laboratoriesISO Guide 34 General Requirementsrequirements for the Competence of Reference Material Producerscompetence of referencematerial producers3. Terminology3.1 Definitions:3.1.1 apparent viscosity, nthe determined viscosity obtained by
9、 use of this test method.3.1.2 digital contact thermometer (DCT), nan electronic device consisting of a digital display and associated temperaturesensing probe.3.1.2.1 Discussion1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and
10、is the direct responsibility of SubcommitteeD02.07 on Flow Properties.Current edition approved May 1, 2017June 1, 2018. Published May 2017July 2018. Originally approved in 1979. Last previous edition approved in 20142017 asD3829 14.D3829 17. DOI: 10.1520/D3829-17.10.1520/D3829-18.2 Available from Am
11、erican National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be
12、technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of
13、this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1This device consists of a temperature sensor connected to a measuring instrument; this instrument measures the temperature-dependent quantity of the sensor, computes the tem
14、perature from the measured quantity, and provides a digital output. This digitaloutput goes to a digital display and/or recording device that may be internal or external to the device. These devices are sometimesreferred to as “digital thermometers.”3.1.2.2 DiscussionPET is an acronym for portable e
15、lectronic thermometers, a subset of digital contact thermometers (DCT).3.1.3 Newtonian oil or fluid, nan oil or fluid that at a given temperature exhibits a constant viscosity at all shear rates or shearstresses.3.1.4 non-Newtonian oil or fluid, nan oil or fluid that at a given temperature exhibits
16、a viscosity that varies with changingshear stress or shear rate.3.1.5 viscosity, nthe ratio between the applied shear stress and rate of shear. It is sometimes called the coefficient of dynamicviscosity. This value is thus a measure of the resistance to flow of the liquid. The SI unit of viscosity i
17、s the pascal second (Pas).3.2 Definitions:Definitions of Terms Specific to This Standard:3.2.1 apparent viscosity, borderline pumping temperature, nthe determined viscosity obtained by use of this testmethod.maximum temperature at which the critical yield stress or critical viscosity occurs, whichev
18、er is the higher temperature.3.2.2 calibration oils, nthose oils for establishing the instruments reference framework of apparent viscosity versus speedfrom which the apparent viscosities of test oils are determined.3.2.3 digital contact thermometer (DCT), critical viscosity, nan electronic device c
19、onsisting of a digital display and associatedtemperature sensing probe.the maximum viscosity at a defined shear rate to allow adequate flow of oil to the oil pump in anautomotive engine. A higher viscosity can cause failure to maintain adequate oil pressure through the limiting of flow through theoi
20、l screen or oil inlet tubes.3.1.2.1 DiscussionThis device consists of a temperature sensor connected to a measuring instrument; this instrument measures the temperature-dependent quantity of the sensor, computes the temperature from the measured quantity, and provides a digital output. This digitalo
21、utput goes to a digital display and/or recording device that may be internal or external to the device. These devices are sometimesreferred to as “digital thermometers.”3.1.2.2 DiscussionPET is an acronym for portable electronic thermometers, a subset of digital contact thermometers (DCT).3.2.4 Newt
22、onian oil or fluid, critical yield stress, nan oil or fluid that at a given temperature exhibits a constant viscosity atall shear rates or shear stresses.the maximum yield stress that allows oil to flow to the inlet oil screen in an automotive engine.With a higher yield stress, air may be drawn into
23、 the pump and cause failure to maintain adequate oil pressure through air-bindingof the pump.3.1.4 non-Newtonian oil or fluid, nan oil or fluid that at a given temperature exhibits a viscosity that varies with changingshear stress or shear rate.3.2.5 shear rate, nthe velocity gradient in fluid flow.
24、 For a Newtonian fluid in a concentric cylinder rotary viscometer in whichthe shear stress is measured at the inner cylinder surface (such as the apparatus being described), and ignoring any end effects, theshear rate is given as follows: 5 2Rs2Rs22R r2! (1) 5 4piRs2tRs22Rr2! (2)where: = shear rate
25、at the surface of the rotor in reciprocal seconds, s1, = angular velocity, rad/s,Rs = stator radius, mm,Rr = rotor radius, mm, andt = time in seconds for one revolution of the rotor.For the specific apparatus being described in 6.1.1,D3829 182 563t (3)3.2.5.1 DiscussionFor a Newtonian fluid in a con
26、centric cylinder rotary viscometer in which the shear stress is measured at the inner cylinder surface(such as the apparatus described in 6.1), and ignoring any end effects, the shear rate is given as follows: 5 2Rs2Rs22R r2! (1) 5 4piRs2tRs22Rr2! (2)where: = shear rate at the surface of the rotor i
27、n reciprocal seconds, s1, = angular velocity, rad/s,Rs = stator radius, mm,Rr = rotor radius, mm, andt = time in seconds for one revolution of the rotor.For the specific apparatus being described in 6.1.1, 563t (3)3.2.6 shear stress, nthe motivating force per unit area for fluid flow. Area is the ar
28、ea under shear. For the rotary viscometerbeing described, the rotor surface is the area under shear.Tr59.81MRo1Rt!31026 (4) 5 Tr2piRr2h 3109 (5)where:Tr = torque applied to rotor, Nm,M = applied mass, g,Ro = radius of the shaft, mm,Rt = radius of the thread, mm, = shear stress at the rotor surface,
29、Pa, andh = height of the rotor, mm.For the dimensions given in 6.1.1,Tr 531.7M 31026 (6) 53.5M (7)3.2.6.1 DiscussionFor the rotary viscometer being described in 6.1, the rotor surface is the area under shear or the shear area. For this test method,end effects are not considered.Tr59.81MRo1Rt!31026 (
30、4) 5 Tr2piRr2h 3109 (5)where:Tr = torque applied to rotor, Nm,M = applied mass, g,Ro = radius of the shaft, mm,Rt = radius of the thread, mm, = shear stress at the rotor surface, Pa, andh = height of the rotor, mm.For the dimensions given in 6.1.1,Tr531.7M 31026 (6)D3829 183 53.5M (7)3.2.7 test oil,
31、 nany oil for which the apparent viscosity and yield stress are to be determined by use of the test method underdescription.3.2.8 viscosity, yield stress, nthe ratio between the applied shear stress and rate of shear. It is sometimes called the coefficientof dynamic viscosity. This value is thus a m
32、easure of the resistance to flow of the liquid. The SI unit of viscosity is the pascalsecond (Pas).shear stress required to initiate flow.3.2.8.1 DiscussionFor all Newtonian fluids and some non-Newtonian fluids, yield stress is zero. An oil can have a yield stress that is a function ofits low-temper
33、ature cooling rate, soak time, and temperature.3.2 Definitions of Terms Specific to This Standard:3.2.1 borderline pumping temperature, nthe maximum temperature at which the critical yield stress or critical viscosityoccurs, whichever is the higher temperature.3.2.2 calibration oils, nthose oils for
34、 establishing the instruments reference framework of apparent viscosity versus speedfrom which the apparent viscosities of test oils are determined.3.2.3 critical viscosity, nthe maximum viscosity at a defined shear rate to allow adequate flow of oil to the oil pump in anautomotive engine. A higher
35、viscosity can cause failure to maintain adequate oil pressure through the limiting of flow through theoil screen or oil inlet tubes.3.2.4 critical yield stress, nthe maximum yield stress that allows oil to flow to the inlet oil screen in an automotive engine.With a higher yield stress, air may be dr
36、awn into the pump and cause failure to maintain adequate oil pressure through air-bindingof the pump.3.2.5 test oil, nany oil for which the apparent viscosity and yield stress are to be determined by use of the test method underdescription.3.2.6 yield stress, nthe shear stress required to initiate f
37、low. For all Newtonian fluids and some non-Newtonian fluids, yieldstress is zero. Some engine oils have a yield stress that is a function of their low-temperature cooling rate, soak time, andtemperature.4. Summary of Test Method4.1 An engine oil sample is cooled from 80 C to the desired test tempera
38、ture at a nonlinear programmed cooling rate over a10 h period and held at the test temperature for the remainder of a 16 h period. After completion of the soak period, two standardtorques of increasing severity are applied to the rotor shaft and the speed of rotation in each case is measured. From t
39、he resultsat three or more temperatures, the borderline pumping temperature is determined.4.2 Alternatively, for some specification or classification purposes it may be sufficient to determine that the BPT is less than acertain specified temperature.5. Significance and Use5.1 Borderline pumping temp
40、erature is a measure of the lowest temperature at which an engine oil can be continuously andadequately supplied to the oil pump inlet of an automotive engine.6. Apparatus6.1 Mini-Rotary Viscometer,3consisting of one or more viscometric cells including a calibrated rotor-stator assembly, which areco
41、ntained in a temperature-controlled aluminum block.6.1.1 The viscometric cell has the following nominal dimensions:Diameter of rotor 17.06 mm 0.08 mmLength of rotor 20.00 mm 0.14 mmInside of diameter of cup 19.07 mm 0.08 mmRadius of shaft 3.18 mm 0.13 mmRadius of string 0.1 mm6.2 Weights:6.2.1 Yield
42、 Stress MeasurementA set of nine disks and a disk holder, each with a mass of 10 g 6 0.1 g.6.2.2 Viscosity MeasurementWeight with mass of 150 g 6 1.0 g.3 The sole source of supply of the apparatus known to the committee at this time is Cannon Instrument Co., P.O. Box 16, State College, PA 16801. If
43、you are aware ofalternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsibletechnical committee,1 which you may attend.D3829 1846.3 Temperature Measuring DeviceUse either a DCT meeting the
44、requirements described in 6.3.1 or liquid-in-glassthermometers as described in 6.3.2. A calibrated DCT or calibrated low temperature liquid-in-glass thermometer shall be used asthe thermometer for temperature measurement below 25 C independent of the instruments temperature control, and shall beloca
45、ted in the thermowell.NOTE 1The display device and sensor must be correctly paired. Incorrect pairing will result in temperature measurement errors and possiblyirreversible damage to the electronics of the display.6.3.1 Digital contact thermometer requirements:Criteria Minimum RequirementsDCT E2877
46、Class BTemperature range 45 C to 100 CDisplay resolution 0.1 C minimum, preferably 0.01 CSensor type RTD, such as a PRT or thermistorSensor,metal sheathed3 mm O.D. with an sensing element less than 30 mm in length to be used with a thermowellsleeve, 6 mm O.D. 58 mm long with a 3 mm hole in center.Se
47、nsor,glass sheathed6 mm O.D. with a sensing element less than 12 mm in lengthDisplay accuracy 50 mK (0.05 C) for combined probe and sensorResponse time less than or equal to 25 s as defined in Specification E1137Drift less than 50 mK (0.05 C) per yearCalibration Error less than 50 mK (0.05 C) over t
48、he range of intended use.Calibration Range 40 C to 85 CCalibration Data 4 data points evenly distributed over the range of 40 C to 1 C and included in calibrationreport.Calibration Report From a calibration laboratory with demonstrated competency in temperature calibration which istraceable to a nat
49、ional calibration laboratory or metrology standards bodyNOTE 2With respect to DCT probe immersion depth, a procedure to determine minimum depth can be found in Guide E2877, Section 5.3, or TestMethods E644, Section 7.6.3.1.1 The DCT calibration drift shall be checked at least annually by either measuring the ice point or against a referencethermometer in a constant temperature bath at the prescribed immersion depth to ensure compliance with 6.3.1. With respect toan
