1、Designation: D6278 17Standard Test Method forShear Stability of Polymer Containing Fluids Using aEuropean Diesel Injector Apparatus1This standard is issued under the fixed designation D6278; the number immediately following the designation indicates the year oforiginal adoption or, in the case of re
2、vision, 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. Scope*1.1 This test method covers the evaluation of the shearstability of polymer-containing fluids. The te
3、st method mea-sures the percent viscosity loss at 100 C of polymer-containing fluids when evaluated by a diesel injector apparatusprocedure that uses European diesel injector test equipment.The viscosity loss reflects polymer degradation due to shear atthe nozzle.NOTE 1Test Method D2603 has been use
4、d for similar evaluation ofshear stability; limitations are as indicated in the significance statement.No detailed attempt has been undertaken to correlate the results of this testmethod with those of the sonic shear test method.NOTE 2This test method uses test apparatus as defined in CECL-14-A-93.
5、This test method differs from CEC-L-14-A-93 in the period oftime required for calibration.NOTE 3Test Method D5275 also shears oils in a diesel injectorapparatus but may give different results.NOTE 4This test method has different calibration and operationalrequirements than withdrawn Test Method D394
6、5.NOTE 5Test Method D7109 is a similar procedure that measures shearstability at both 30 and 90 injection cycles. This test method uses 30injection cycles only.1.2 The values stated in SI units are to be regarded as thestandard.1.2.1 ExceptionNon-SI units are provided in parentheses.1.3 This standar
7、d 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 and health practices and determine the applica-bility of regulatory limitations prior to use. Specific precau-tionary statem
8、ents are given in Section 8.2. Referenced Documents2.1 ASTM Standards:2D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Calculation of Dynamic Viscos-ity)D2603 Test Method for Sonic Shear Stability of Polymer-Containing OilsD5275 Test Method for Fuel Injector Shear Stab
9、ility Test(FISST) for Polymer Containing FluidsD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System PerformanceD7109 Test Method for Shear Stability of Polymer Contain-ing Fluids Using a European Diesel Injector Apparatus a
10、t30 and 90 Cycles2.2 Coordination European Council (CEC) Standard:3CEC L-14-A-93 Evaluation of the Mechanical Shear Sta-bility of Lubricating Oils Containing Polymers3. Terminology3.1 Definitions:3.1.1 kinematic viscosity, na measure of the resistance toflow of a fluid under gravity.3.2 Definitions
11、of Terms Specific to This Standard:3.2.1 calibration pressure, nthe recorded gauge pressurewhen calibration fluid RL233 undergoes a viscosity loss of2.70 mm2/s to 2.90 mm2/s when the recorded gauge pressure iswithin the range of 13.0 MPa to 18.0 MPa.3.2.2 percent viscosity loss, nviscosity loss, as
12、defined in3.2.3, divided by the pre-sheared viscosity, and reported as apercent.3.2.3 viscosity loss, nthe loss in viscosity determined fromthe difference in kinematic viscosity at 100 C of pre-shearedand post-sheared fluid.4. Summary of Test Method4.1 A polymer-containing fluid is passed through a
13、dieselinjector nozzle at a shear rate that causes polymer molecules todegrade. The resultant degradation reduces the kinematic1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.07 on
14、 Flow Properties.Current edition approved Jan. 1, 2017. Published February 2017. Originallyapproved in 1998. Last previous edition approved in 2012 as D6278 121. DOI:10.1520/D6278-17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.
15、org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from CEC Secretariat, Interlynk Administrative Services, Ltd., LynkHouse, 17 Peckleton Lane, Desford, Leicestershire, LE9 9JU, United Kingdom.*A Summary of Changes sec
16、tion appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision o
17、n Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1viscosity of the fluid under test. The percent viscosity loss is ameasure of the mechanical shear stability of the polymer-contai
18、ning fluid.5. Significance and Use5.1 This test method evaluates the percent viscosity loss forpolymer-containing fluids resulting from polymer degradationin the high shear nozzle device. Thermal or oxidative effectsare minimized.5.2 This test method is used for quality control purposes bymanufactur
19、ers of polymeric lubricant additives and their cus-tomers.5.3 This test method is not intended to predict viscosity lossin field service in different field equipment under widelyvarying operating conditions, which may cause lubricant vis-cosity to change due to thermal and oxidative changes as wella
20、s by the mechanical shearing of polymer. However, when thefield service conditions, primarily or exclusively, result in thedegradation of polymer by mechanical shearing, there may bea correlation between the results from this test method andresults from the field.6. Apparatus6.1 The apparatus consis
21、ts of a fluid reservoir, a double-plunger pump with an electric motor drive, an atomizationchamber with a diesel injector spray nozzle, and a fluid coolingvessel, installed in an area with an ambient temperature of20 C to 25 C (68 F to 77 F). Fig.A1.1 shows the schematicrepresentation of equipment.6
22、.1.1 Fluid Reservoir, In Fig.A1.1, the fluid reservoir (7)4isopen on the top, has approximately a 250 mL capacity withgradation of a maximum of 5 mL, has a 45 mm (1.772 in.)inner diameter, and is calibrated in units of volume. It is fittedwith an internal fluid distributor as detailed in Fig. A1.2.A
23、40 mm (1.575 in.) diameter watch glass with serrated edges isan acceptable distributor plate. The distributor reduces thetendency of fluid channeling. Temperature is measured by athermometer suspended in the center of the fluid reservoir. Thebottom of the thermometer bulb shall be 10 mm to 15 mmabov
24、e the entrance to the drain tube opening. Othertemperature-measuring equipment positioned at the same lo-cation may also be used. The outlet is equipped with athree-way stopcock (8). The three-way stopcock is of a conetype with a nonexchangeable solid plug with an 8 mm(0.315 in.) nominal bore size.
25、Transparent, plastic tubing (10)in Fig. A1.1, is used to connect the three-way stopcock to thepump inlet.6.1.2 Double-Plunger Injection Pump, In Fig. A1.1 (11) isdefined as Bosch PE 2 A 90D 300/3 S2266. This pump isequipped with a stroke counter (15), venting screw (14), andflow rate adjusting screw
26、 (12).6.1.3 Injection Pump, driven by a three-phase electric motor(13) in Fig. A1.1, rated at a speed of 925 r min 6 25 r min.6.1.3.1 This motor runs at 925 r min on the 50 Hz currentprevalent in Europe; it will run at approximately 1100 r min on60 Hz current. The 1100 r min speed is not acceptable
27、in thisprocedure. A suitable means shall be taken to ensure theprescribed 925 r min 6 25 r min speed to the injection pump.One acceptable method is to usea6to5speed reducer.6.1.4 Outlet of Injection Pump, connected to the atomizationchamber using high pressure steel tubing. The atomizationchamber (2
28、) in Fig. A1.1 is defined in more detail in Fig. A1.3.To minimize foam generation, the spray chamber is designedso that the fluid under test exits from the nozzle into a chamberfilled with the test fluid.Adrain tube (17) fitted with a two-waystopcock is included to minimize contamination from thepre
29、vious test during the system cleaning steps. The dieselinjector nozzle is a Bosch DN 8 S 2-type pintle nozzle injector,number 0434 200 012, installed in a Bosch KD 43 SA 53/15nozzle holder. The nozzle holder includes a filter cartridge.NOTE 6Take great care to avoid damage to the precision parts of
30、thefuel injection equipment (the plunger and barrel in the pump and thenozzle valve assembly). Service work on the equipment should beperformed by a diesel fuel injector pump specialist or with reference to themanufacturers service manual.5NOTE 7An unusual rapid rise in gauge pressure during testing
31、 maysignify filter blockage. When this occurs, the filter cartridge shall bereplaced.6.1.5 A pressure sensing device (18), such as a glycerol-filled pressure gauge or electronic, digital display pressureindicator, shall be installed and separated from the line by apressure snubber or needle valve to
32、 suitably dampen pressuresurges. The pressure sensing device shall be able to takereadings with a display resolution of at least 0.1 MPa when aglycerol-filled pressure gauge is being used, or to 0.01 MPawhen an electronic pressure device is employed. The pressuredevice shall be occasionally pressure
33、 tested to ensure accuracy.6.1.6 Fluid Cooling Vessel, (5) in Fig. A1.1), used tomaintain the specified temperature of the test fluid, as indicatedat the outlet of the fluid reservoir. This vessel is a glasscontainer with exterior cooling jacket constructed so that theheat transfer surface of the ja
34、cket is spherical. The exteriorjacket diameter, d1, is approximately 50 mm (1.969 in.). Theinterior heat transfer surface, d2, is approximately 25 mm(0.984 in.) in diameter. The overall length, L, is approximately180 mm (7.087 in.). A distributor plate, similar in design to thedistributor plate in t
35、he fluid reservoir, is positioned in the upperportion of the fluid cooling vessel to ensure contact betweenthe fluid and the cooling surface. The discharge from the fluidcooling vessel is through a three-way stopcock of the samedesign used on the discharge of the fluid reservoir. If using arate-depe
36、ndent chiller, the exterior cooling jacket shall besupplied with an adjustable volume of cold water.7. Materials7.1 Diesel Fuel (No. 2), initially required to adjust the dieselinjector nozzle valve opening pressure.7.2 Calibration Fluid RL233, used to ensure that when theapparatus is adjusted to wit
37、hin a prescribed pressure range, thecorrect viscosity loss is obtained.4The number in parentheses refers to the legend in Fig. A1.1.5Repair Instructions for Diesel Injection Pumps Size A, B, K and Z, BulletinWJP101/1 B EP, Robert Bosch GmbH, 2800 South 25thAve., Broadview, IL60153.D6278 172NOTE 8RL2
38、33 meets the requirements of this test method and isacceptable during a transition period between suppliers. See researchreport for details.68. Hazards8.1 WarningUse a safety shield between the high-pressurecomponents and the operator during use of equipment.8.2 PrecautionDuring operation, the line
39、between thepump and nozzle, (16) in Fig. A1.1), is under a pressure of atleast 13.0 MPa (130 bar, or 1885 psi). Pressures above theupper limit of 18.0 MPa (180 bar or 2611 psi) are possible iffilter plugging occurs. Shut off the pump prior to tightening anyfitting that is not properly sealed.9. Samp
40、ling9.1 Approximately 600 mL of fluid is needed per test.9.2 The test fluid shall be at room temperature, uniform inappearance, and free of any visible insoluble material prior toplacing in the test equipment.9.3 Water and insolubles shall be removed before testing, orfilter blocking and nozzle wear
41、 may occur. Filter blocking canbe detected by a sudden change in gauge pressure. Thetransport of insolubles to the shear zone will shorten nozzlelife.10. Calibration and Standardization10.1 Nozzle AdjustmentsIf the nozzle to be used is new orhas not been pre-calibrated, adjust the diesel injector no
42、zzleholder with the nozzle in place. Adjust the nozzle using dieselfuel and a nozzle tester so that the valve opening pressure is13.0 MPa (1885 psi) under static conditions. If the nozzle hasbeen pre-calibrated with RL233 calibration oil, adjust the valveopening pressure to the calibration pressure
43、prescribed, whichmust be between 13.0 MPa and 18.0 MPa (2611 psi).10.1.1 Install the nozzle and the nozzle holder in the testapparatus. The pintle/spray nozzle shall be tightly fitted in thechamber to avoid leakage of oil around the external surface ofthe spray nozzle.10.2 Measurement of Residual Un
44、drained Volume, Vres:10.2.1 The residual undrained oil volume of the system isthe volume of the system between the three-way stopcockbelow the fluid reservoir (8) in Fig. A1.1, and the injectornozzle orifice (1). Vresdoes not include the atomizationchamber volume. When the residual undrained volume
45、isknown, go to 10.4.10.2.2 To determine residual undrained volume, first re-move as much fluid as possible by briefly running the pump.10.2.3 Remove the high-pressure lines (16) in Fig. A1.1,and drain. Remove the plug at the end of the pump gallery todrain the remaining oil in the pump. Drain atomiz
46、ationchamber (2).10.2.4 Reassemble the system and close all drains. Theupper three-way stopcock (6) shall be open to the lowerreservoir (7) and the lower three-way cock (8) shall be open tothe pump suction (10).10.2.5 Add 170 mL of RL233 calibration oil to the lowerreservoir (7) and observe the leve
47、l. Start the pump and run forseveral minutes until the oil is transparent and free of sus-pended air.10.2.6 Stop the pump. Drain the fluid in the atomizationchamber into a beaker and then pour the fluid back into thelower reservoir; draining to waste will result in an error in themeasurement of Vres
48、. Allow the system to drain for 20 min andfree air trapped in the transparent connecting tube between thelower reservoir and pump.10.2.7 Observe the difference in oil level in the lowerreservoir compared to that noted in 10.2.5. Record this differ-ence as the residual volume, Vres.NOTE 9Undrained re
49、sidual volumes of 15 mL to 30 mL have beenreported by various users of this test. Vresmeasurements in excess of thismay occur when fluid in the atomization chamber is not poured back intothe lower reservoir as in 10.2.6, or if the length of line (10) is excessive.10.2.8 Calculate the run volume, Vrun, which is the subtrac-tive difference between 170 mL and Vres.10.3 Warm-upA half-hour warm up period is requiredbefore proceeding to calibrate with RL233. Set the strokecounter shut-off to 30 times n strokes, and start the pump.NOTE 10This warm-up per