1、Designation: E 1844 08Standard Specification forA Size 10 3 45 Smooth-Tread Friction Test Tire1This standard is issued under the fixed designation E 1844; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、 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 specification covers the general requirements for asmooth-tread standard tire for measuring tire-pavement frictionforces.1.2 The
3、values stated in SI units are to be regarded as thestandard. The values given in parentheses are provided forinformation purposes only.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 est
4、ablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 297 Test Methods for Rubber ProductsChemicalAnalysisD 412 Test Methods for Vulcanized Rubber and Thermo-plastic ElastomersTensionD 1054
5、 Test Method for Rubber PropertyResilience Us-ing a Goodyear-Healey Rebound PendulumD 1765 Classification System for Carbon Blacks Used inRubber ProductsD 2240 Test Method for Rubber PropertyDurometerHardnessD 3182 Practice for RubberMaterials, Equipment, andProcedures for Mixing Standard Compounds
6、and Prepar-ing Standard Vulcanized SheetsE 867 Terminology Relating to Vehicle-Pavement Systems2.2 Other Document:GriptesterGTSV1 Descriptive Booklet33. Terminology3.1 Terminology used in this specification is in accordancewith Terminology E 867.4. Materials and Manufacture4.1 The individual standar
7、d tires shall conform to the designstandards of Section 6. Dimensions, weights, and permissiblevariations are also given in Section 6 and Fig. 1 and Fig. 2.4.2 Tread compounding, fabric processing, and all tiremanufacturing shall be certified to ensure that the specifica-tions are met (see Section 8
8、).4.3 The markings on the tire, as shown in Fig. 1, shall bemolded on the sides of the tire.4.4 Fig. 1 shows a view of the tread surface and a side viewof the tire. Fig. 2 is a typical tire cross-section with criticaldimensions identified.4.5 Tire should be mounted so that it is rotated in thedirect
9、ion of the arrow on the side of the tire. See Fig. 1.5. Material Requirements5.1 The compounding requirements for the tread compoundare given in Table 1.5.2 The fabric shall be Nylon, 1260/2 Denier.NOTE 1Certain proprietary products have been specified since exactduplication of properties of the fin
10、ished tire may not be achieved withother similar products. This inclusion does not in any way comprise arecommendation for these proprietary products nor against similar prod-ucts of other manufacturers, nor does it imply any superiority over anysuch similar products.6. Physical Requirements6.1 The
11、physical and mechanical test requirements of thetread compound are given in Table 2.7. Construction, Dimensions and Permissible Variations7.1 ConstructionThe tire shall be size 10 3 45, tubetype, two plies, nylon cord, and bias construction.7.2 DimensionsTread width shall be 51 6 2.0 mm (2.0 60.08 i
12、n.), the tread radius shall be 165 6 25 mm (6.5 6 1.0 in.),the cross-sectional width shall be 102 6 2 mm (4.0 6 0.08 in.),and the outside diameter at the centerline shall be 258 6 2mm(10.15 6 0.08 in.) when measured on a 89 mm (3.5 in.) wide1This specification is under the jurisdiction ofASTM Commit
13、tee E17 on Vehicle- Pavement Systems and is the direct responsibility of Subcommittee E17.24 on Tireand Slider Characteristics.Current edition approved June 1, 2008. Published June 2008. Originallyapproved in 1996. Last previous edition approved in 2006 as E 1844 06.2For referenced ASTM standards, v
14、isit 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 ASTM website.3Available from Findlay-Irvine Ltd., Bog Road, Penicuik, MidlothianEH269BU, Scotland.1Copyrigh
15、t ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.rim at 138 6 3 kPa (20 6 0.5 PSI). See Fig. 2 which shows theinflated dimensions of the new tire.7.3 TreadThe tread surface shall be smooth (blank) with-out any ribs or grooves. The tread shall
16、have a thickness of 5mm (0.20 in.) and an undertread thickness of 2 6 0.5 mm (0.086 0.02 in.) at the tread centerline.7.4 Wear IndicatorsThere will be two holes molded intothe tire tread, 5.0 mm (0.20 in.) deep and 3.2 mm (0.125 in.) indiameter. These two wear-indicators will be spaced 180 apart.8.
17、Workmanship8.1 Tires shall be free of defects in workmanship andmaterial.9. Test Methods9.1 For information on the following, refer to the ASTMstandards listed.9.1.1 Tensile Sheet CurePractice D 3182.9.1.2 Modulus (300 %)Test Methods D 412.9.1.3 Tensile Sheet DurometerTest Method D 2240, usinga Type
18、 A Shore Durometer.9.1.4 Restored Energy (Rebound or Resilience)TestMethod D 1054.9.1.5 Specific GravityTest Method D 297.FIG. 1 Molded on Tire: 10 3 45 Tread ASTM Batch No.FIG. 2 Tire SectionInflated DimensionsTABLE 1 Compounding of Tread RubberAMaterial PPHRSBR 1712B89.38BR 1208C35.00Zinc oxide 3.
19、00Stearic acid 2.00Paraffin wax 2.00N339D75.006PPDE2.00High aromatic oil 22.12TBBSF1.10DPGG0.10Sulfur 1.80ASee Practice D 3182.BStyrene-butadiene rubber (23.5 % styrene) 37.5 parts of high-aromatic oil.CHigh cis-polybutadiene.DN339 Carbon Black, see Classification D 1765.EDimethyl butylphenyl phenyl
20、enediamine.FButyl benzothiazole sulfenamide.GDiphenyl guanidine.TABLE 2 Physical Properties of Tread CompoundTensile Sheet Cure, min. at 302F (150C) 30300 % modulus, psi (Test Methods D 412) 1000 6 200Specific gravity (Test Methods D 297) 1.13 6 0.02Tensile strength, min psi (Test Methods D 412) 200
21、0Elongation, min % (Test Methods D 412) 500Tire tread durometer (Test Method D 2240)586 2E18440829.1.6 Tensile StrengthTest Methods D 412.9.1.7 ElongationTest Methods D 412.9.1.8 Tire Tread DurometerTest Method D 2240, in addi-tion to the following specific procedures:9.1.8.1 Use a Type A Durometer.
22、 A12.7 mm (0.5 in.)diameter presser foot, a sure code XAHAF is recommended.9.1.8.2 The Durometer shall be calibrated at a reading of 60hardness.9.1.8.3 Condition the tire and durometer to equilibrium at23 6 2C (73.4 6 3.6F) before determining tread hardness.9.1.8.4 Determine the tire tread hardness
23、by averaging atleast one set of six readings. A set should consist of readingstaken at approximately equally spaced intervals around thetread circumference.9.1.8.5 Apply the presser foot to the tire tread as rapidly aspossible without shock, keeping the foot parallel to the treadsurface. Apply just
24、sufficient pressure to obtain firm contactbetween the presser foot and tire tread surface. Read thedurometer scale within 1 s after the presser foot is in contactwith the tread, but after initial maximum transient which mayoccur immediately after contact is made.10. Precision and Bias10.1 Precision
25、standards are currently under development.11. Certification11.1 Tires are to be inflated and measured prior to shipment.Upon request, the manufacturer shall furnish the purchaserwith certification that the test tire meets this specification.11.2 The Annex to this specification suggests a test proce-
26、dure for determining the reliability, performance and consis-tency of the tires.11.3 All tires under certification shall be subject to themanufacturers normal variation.12. Packaging and Preservation12.1 Tires should be stored in a dry area, at a temperaturenot exceeding 32.2C (90F) and in subdued l
27、ight. Tires mustnot be stored near electric motors, welders, or other ozonegenerating equipment.13. Recommendations for Tire Use and OperationalRequirements13.1 The tire was designed for measuring tire-pavementfriction forces only and was not designed for any other use orservice.13.2 Anew tire break
28、-in sufficient to only remove the glossytread surface is recommended before using the tire for testing.This break-in time will vary with pavement surface condition,speed, and test tire operating mode, but is normally 511 km(37 miles).13.3 The inflation pressure used in the test tire shall be 1386 3
29、kPa (20 6 0.5 PSI) measured at ambient temperature(cold). The maximum permitted inflation is 275 kPa (40 PSI).13.4 The recommended static test load on the test tire shallbe 21 kg (46 lbs).13.5 When any irregular wear or damage results from thetesting or when the wear indicators are no longer visible
30、, theuse of the tire as a standard friction test tire shall bediscontinued.NOTE 2Caution: The measured friction number may be influencedby tire age or tread hardness, or both. The magnitude of this dependencehas not been exactly determined, but aging which has increased treadhardness to 65 will infl
31、uence the resultant friction forces on some types ofpavements.14. Keywords14.1 friction test tire; size 10 6, 45ANNEX(Mandatory Information)A1. SUGGESTED PROCEDURE FOR TESTING AND DOCUMENTING MEASURING TIRESA1.1 IntroductionA1.1.1 The purpose of this procedure is to ensure that allmeasuring tires gi
32、ve friction readings which match the “stan-dard.” This standard is defined in terms of a referencemeasuring tire or calibration tire.A1.1.2 For continuity, there shall be three calibration tires:two in active use and one master calibration tire held in reservefor calibration tire testing. These tire
33、s are selected from thosethat have passed the standard procedure for testing withparticularly stringent conditions (see paragraph A1.4 below).A1.1.3 The three current calibration tires must undergo themonthly cross-check set out in section A1.5 below.A1.1.4 All tires must be manufactured from the ru
34、bbercompound defined in Specifications E 1551, E 501, and E 524.A1.2 Incoming Goods InspectionA1.2.1 On receipt of a batch of tires from the manufacturer,every tire must be visually examined for a batch number,rubber formulation stamp, and physical imperfections. Tiresfailing visual inspection must
35、be returned to the manufacturer.A1.2.2 Tires which have passed visual inspection must bemarked in bright metallic paint with an individual serialnumber showing the type of tire, batch number, and tirenumber. For example, A-08-21. These numbers must beentered in the tire log book which will subsequen
36、tly show theE1844083date of test, whether it passed or failed, and (when appropriate)to where it was dispatched.A1.3 Running in of New TiresA1.3.1 The tires, together with their inner tubes, must bemounted on rims and inflated to 138 6 3 kPa (20 6 1 psi) andthen run-in on a friction tester. The mile
37、age required dependson the temperature and moisture on the road surface at the timeand varies from 5 to 11 km (3 to 7 miles), at 50 to 65 kmH(3040 mph). The tire must be considered “run-in” when thecentral molding flash is no longer visible.A1.4 Test ProcedureA1.4.1 The mounted and run-in tires must
38、 be road-tested foraccuracy of their friction readings, according to the followingprocedure:A1.4.1.1 Test ConditionsThe test must be made accordingto the following rules:A1.4.1.1.1 Tires must be tested within nine months ofmanufacture and hardness recorded.A1.4.1.1.2 All tires must be inflated to 13
39、8 6 3 kPa (20 61 psi).A1.4.1.1.3 All tires must travel at least 1 km (0.6 mile)before entering the test section, and for the last 200 metres (220yds), the surface must be wetted so that the surface is coveredwith at least 0.5 mm (.02 in.) of water.A1.4.1.1.4 A properly calibrated friction tester mus
40、t beused. Comparisons must only be made between runs carriedout using the same friction tester.A1.4.1.1.5 Comparisons must only be made between runscarried out on the same day and under the same conditions ofroad state, moisture and temperature. If the ambient tempera-ture changes more than 5C (9F)
41、or if precipitation conditionschange, the procedure must be restarted.A1.4.1.1.6 Test runs must be made ona1km(0.6 mile)length of straight road, surfaced with hot-rolled-asphalt. Eachone third of each side of this test length must be regarded as aseparate test section.A1.4.2 Calculation of Calibrati
42、on Friction NumbersA1.4.2.1 Because testing is carried out on surfaces whosefriction characteristics are not constant, the first stage of thetesting procedure must always be to obtain a current set offriction numbers for the six test sections used.A1.4.2.2 With a calibration tire mounted, a run cove
43、ring allsix test sections (that is, an outward and return run) must bemade and the average friction number for each section calcu-lated. This double run must be repeated, and the averagefriction number for each section calculated again.A1.4.2.3 By this means, two average friction numbers willhave be
44、en obtained for each of the six sections. These twoaverage friction numbers should differ by no more than 0.03.A1.4.2.4 If this condition is met, a calibration frictionnumber for each section must be formed by averaging the twoaverages for that section.A1.4.2.5 If this condition is not met, the doub
45、le run mustagain be carried out until two double runs are obtained whichdo satisfy the condition.A1.4.3 Acceptance Criteria for Production TiresA1.4.3.1 With the new tire mounted, a run covering three ofthe test sections must be made and the average friction numberfor each section calculated. If the
46、 friction number for each ofthe three sections is within 0.02 of the calibration average, thetire is passed.A1.4.3.2 If at least one of the average friction numbers isnot within 0.02 of the calibration average but each of theaverage friction numbers is within 0.03 of the calibrationaverage, then a r
47、eturn run must be made; if the friction numberfor each section is again within 0.03 of the calibration average,the tire is passed.A1.4.3.3 If the reading for one section has to be discarded(because of obstruction or contamination) a return run is made;five readings which are within 0.03 of the calib
48、ration averageallow the tire to be passed.A1.4.4 Acceptance criteria for calibration tires:A1.4.4.1 The calculation of the six calibration frictionnumbers described in A1.4.2 must be carried out using themaster calibration tire.A1.4.4.2 With the new tire mounted, a run covering three ofthe test sect
49、ions must be made and the average friction numberfor each section calculated. If the friction number for each ofthe three sections is within 0.01 of the calibration average, thetire is passed.A1.4.4.3 If the friction number for each of the three sectionsis only within 0.02 of the calibration average, a return run ismade; if the friction number for each section is again within0.02 of the calibration average, the tire is passed.A1.5 Checks on the Calibration TiresA1.5.1 The life of a master calibration tire in that role mustnot exceed six months,
