1、Designation: F 1502 05e1Standard Test Method forStatic Measurements on Tires for Passenger Cars, LightTrucks, and Medium Duty Vehicles1This standard is issued under the fixed designation F 1502; the number immediately following the designation indicates the year oforiginal adoption or, in the case o
2、f revision, 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.e1NOTEParagraph 6.1.1 was editorially corrected in February 2005.1. Scope1.1 This test method covers meth
3、ods for performing certainmechanical static measurements on tires. The term “static”implies that the tire is not rotating while measurements arebeing made.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard do
4、es 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.2. Referenced Documents2.1 ASTM Sta
5、ndards:2D 2240 Test Method for Rubber PropertyDurometerHardnessF 421 Test Method for Measuring Groove and Void Depthin Passenger Car TiresF 538 Terminology Relating to the Characteristics and Per-formance of TiresF 870 Practice for Tread Footprints of Passenger Car TiresGroove Area Fraction and Dime
6、nsional MeasurementsF 1082 Practice for TiresDetermining Precision for TestMethod Standards3. Terminology3.1 Definitions:3.1.1 outside diameter, nthe maximum diameter of a tirewhen it is mounted and inflated.3.1.2 overall width, nthe maximum cross-sectional widthof a tire, including protective or de
7、corative ribs.3.1.3 tire weight, nthe weight of an unmounted tirewithout tube or flap.3.1.4 tread arc width, nthe length of the arc measuredfrom one extreme of the tread design proper to the oppositeextreme; that is, from shoulder to shoulder perpendicular to thecircumferential center line.3.1.5 tre
8、ad hardness, nthe hardness of an element in thetread design as measured by a designated standard gage.3.1.6 tread radius, nthe radius of a circle whose arc bestfits the tread surface when the radius template used is heldperpendicular to the circumferential center line of an inflatedtire.3.2 For addi
9、tional definitions of terms used in this testmethod, refer to Terminology F 538.4. Significance and Use4.1 Static measurements of tires are important to tire manu-facturers, processing engineers, and vehicle design engineersfor purposes of commerce (in consumer/vendor agreements)and in tire research
10、 and development.4.2 The procedures are sufficiently detailed to achievecommercially acceptable reproducibility among laboratoriesand may therefore be used for specification, compliance, orreference purposes.4.3 Changes attributable to growth after inflation may beobtained by comparing measurements
11、made immediately afterinflation with those made 18 to 24 h later.5. Tire Marking5.1 For measurements other than weight, the tire shall bemarked at six equally spaced locations around the circumfer-ence. Starting at the DOT serial, make radial lines from bead tobead, perpendicular to the tread center
12、 line, at 60-degreeintervals. Number the resulting sections “1” through “6” in aclockwise sequence as viewed from the side containing theserial number.1This test method is under the jurisdiction of ASTM Committee F09 on Tiresand is the direct responsibility of Subcommittee F09.30 on Laboratory (Non-
13、Vehicular) Testing.Current edition approved Jan. 1, 2005. Published January 2005. Originallyapproved in 1994. Last previous edition approved in 1999 as F 1502 94 (1999).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annua
14、l 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.6. Procedures6.1 Tire Weight:6.1.1 Weigh the test tire on a scale with accura
15、cy to 0.045 kg(0.1 lb) in the required range. A scale of 0-90 kg (0-200 lb) hasbeen found to be satisfactory for tires within the scope of thistest method.6.1.2 The scale used should be calibrated with weightstraceable to the National Institute of Standards Technology(NIST).6.2 Outside Diameter:6.2.
16、1 Mount the test tire on a rim of the correct diameter forthe tire size and the measuring rim width listed for that tire inthe current yearbook of the Tire and Rim Association3(orapplicable document4,5), unless another width is chosen.6.2.2 Inflate the tire to the maximum pressure given on thesidewa
17、ll unless another pressure has been chosen. Do notexceed the maximum pressure given on the sidewall. Recordthe value used. Allow 24 h for inflation growth and adjustpressure if necessary.6.2.3 The assembly of wheel and inflated tire shall be intemperature equilibrium with the environment in which th
18、emeasurements are to be made. This can usually be achieved in3 h at room temperature, 24 6 8C (75 6 15F). Recordambient temperature at the time of measurements.6.2.4 Anchor the end of a “diameter” (pi) tape in the treadcenter (or other maximum diameter location, that is, center lowoxbow (Fig. 1), at
19、 any circumferential location. Use a thumb-tack if necessary. See Fig. 2.6.2.5 Carefully align the tape around the tire circumferenceso that it is parallel to the plane of the tread center line. Readand record the indicated diameter.6.3 Overall Width:6.3.1 Mount and condition the test tire as in 6.2
20、.1-6.2.3.6.3.2 Use an outside caliper or other direct-reading devicethat is graduated in 0.25 mm (0.01 in.). See Figs. 3 and 4.6.3.3 The measured overall width shall include protectiveside ribs, bars, and decorations.6.3.4 Section width can be obtained by subtracting heightsof sidewall protuberances
21、 from the overall width obtained in6.3.3.6.3.5 Record individual and average overall width measure-ments from 6.3.3 to the nearest 0.25 mm (0.01 in.) from at leastthree equally spaced circumferential locations as marked in5.1.6.4 Tread Radius:6.4.1 Prepare the tire as in 6.2.1-6.2.3.6.4.2 Tread radi
22、us templates commonly have radii rangingfrom 120 mm (4.75 in.) to 300 mm (12.0 in.) in 12.8-mm(0.50-in.) increments and from 300 mm (12.0 in.) to 900 mm(35.5 in.) in 12.8-mm (0.50-in.) increments. Choose the onethat most closely fits the tread arc defined by one of thefollowing types of contour. See
23、 Fig. 5.NOTE 1For tires outside or different from these most popular treadradius contours, that is, extreme low profile types, identify those radii thatmost closely define the tread contour.6.4.2.1 Type A Single (Primary) (see Fig. 6)This type ischaracterized by a tread arc that can be uniformly con
24、tacted byone of the templates. Choose the one that most closely fits thearc defined by three points, the tread center, and two shoulders.Since a perfectly uniform radius is not always attainable, othertypical variations are discussed as means for arriving at a bestdescriptive fit.6.4.2.2 Type B Dual
25、, Drop Shoulder (see Fig. 7)This typeis characterized by the inability to fit a single-radius templateacross the entire tread because of drops at the shoulders.Choose the one that most closely fits the center portion of thetread, ignoring the shoulder drop. A secondary radius of the3Current yearbook
26、 of the Tire and Rim Association available from the Tire andRim Association, Inc., 175 Montrose Avenue, West, Suite 150, Copley, OH 44321.4Current yearbook of the European Tyre and Rim Technical Organizationavailable from the ETRTO, 32 Avenue Brugmann, 1060 Brussels, Belgium.5Current yearbook of the
27、 Japan Automotive Tire Manufacturers AssociationInc. available from JATMA, 8thfloor, No. 33 Mori Bldg., 3-8-21 ToranomonMinato-ku, Tokyo, Japan 105-0001.FIG. 1 Type C: Tread Contour with a Center-Low OxbowFIG. 2 Outside Diameter MeasurementFIG. 3 Overall Width MeasurementF150205e12shoulders can then
28、 be determined to obtain a more completedescription of the tread contour.6.4.2.3 Type C, Center-Low Oxbow (see Fig. 1)This typeis characterized by a center contour that drops too low to befitted by any of the standard templates. This is the only contourtype for which the central area is not of prime
29、 importance.Choose the template that best fits the intermediate and shoulderareas. Do not confuse Type C with Type B secondary contouras shown in Fig. 7.6.4.2.4 Type D, Center-High Oxbow (see Fig. 8)This typeis characterized by raised center ribs accompanied by adepressed intermediate area and anoth
30、er raised area at theshoulders, so that a gap exists in the mid-point areas. Choosethe template that most closely fits the tread center and bothshoulders.6.5 Tread Hardness:6.5.1 Prepare the test tire as in 6.2.1-6.2.3.6.5.2 Mount the tire/wheel unit in a test fixture or stand it ona smooth surface
31、so that its wheel axis is parallel to thatsurface.6.5.3 An A-scale durometer hardness gage6may be used.Report the brand name of the one chosen.6.5.4 Make measurements in smooth and flat areas of the sixtread sections marked off in 5.1 (see Fig. 9). Avoid placing theprobe near sipes, mold vents, or e
32、dges of tread elements.6.5.5 Results on crown and shoulder elements should berecorded separately since they may differ from each other.6.5.6 Apply the gage rapidly, in a manner prescribed in TestMethod D 2240, in a direction perpendicular to the treadsurface, using enough force to ensure that the ga
33、te plate lies flatagainst the surface.6Shore and Rex typesA-scale durometer hardness gage have been found suitablefor this purpose.FIG. 4 Overall Width MeasurementFIG. 5 Tread Radius MeasurementFIG. 6 Type A: Tread Contour with a Single RadiusFIG. 7 Type B: Tread Contour with a Dual RadiusFIG. 8 Typ
34、e D: Tread Contour with a Center-High Oxbow StyleFIG. 9 Tread Hardness MeasurementF150205e136.5.7 Hardness readings should be taken quickly, within 1 safter the application of force. Report the average hardnessreading, the nearest scale division, for the area measured, thatis, crown or shoulder.6.6
35、Tread Arc Width:6.6.1 Use a flexible steel scale, such as that shown in Fig.10, having scale divisions of 2.50 mm (0.10 in.).6.6.2 Press scale onto the tire tread so that it is perpendicularto the circumferential center line and conforms to the tread arc.6.6.3 Record, to the nearest scale division,
36、at least onemeasurement in each of the three chosen sections.7. Groove (Void) Depths7.1 Static measurements for groove (void) depths are de-scribed in Test Method F 421.8. Gross Footprint Area8.1 Gross footprint area measurements are described in TestMethod F 870.9. Report9.1 Each examiner taking me
37、asurements will need to reportthe data in a logical format and form. Frequent tire measure-ments will necessitate that a standard data reporting form beutilized within ones own company.10. Precision and Bias710.1 This precision and bias section has been prepared inaccordance with Practice F 1082. Pl
38、ease refer to this practicefor terminology and other statistical calculation details.10.2 To develop the data for this precision section a P195/75R14 steel belted radial tire with measurement markings wasmounted on a 6 3 14 rim and circulated to three laboratories ortire testing company locations, f
39、or the various static tiremeasurements as called for in this test method. At eachlaboratory, two different technicians made independent statictire measurements on each of two different days spaced oneday apart. The word “independent” means that the results ofother technicians and the results of the
40、previous day (for thesame technician) were not known or available during themeasurement process.10.3 The P195/75R14 tire was not dismounted for weightmeasurements. An inflation pressure of 26 psi (179 kPa) wasused for all static measurements. A test result is defined as asingle measurement of the pa
41、rticular static tire dimension orproperty.10.4 The results of the precision evaluation are given inTable 1 for the seven static measurements. The results of thistable were calculated by the standard procedures as set forth inPractice F 1082. The within-laboratory variation expressed bySr (and r, (r)
42、 as well), is a pooled (or root mean square average)value across both technicians in all three laboratories. Thebetween-laboratory variation expressed by SR (and R, (R) aswell) is a value that has both a laboratory-to-laboratorycomponent as well as a technician-to-technician component.10.5 Statement
43、s for precision may be made as follows forany static measurement.10.5.1 RepeatabilityThe repeatability, r, of this test mea-surement has been established as the appropriate value tabu-lated in Table 1. Two single test results, obtained under normaltest method procedures, that differ by more than thi
44、s tabulatedr, must be considered as derived from different or non-identicalsample populations.10.5.2 ReproducibilityThe reproducibility, R, of this testmeasurement has been established as the appropriate valuetabulated in Table 1. Two single test results obtained in twodifferent laboratories, under
45、normal test measurement proce-dures, that differ by more than the tabulated R, must beconsidered to have come from different or non-identical samplepopulations.10.5.3 Repeatability and reproducibility expressed as apercentage of the mean level, (r) and (R), have equivalentapplication statements as a
46、bove for r and R. For the (r) and (R)statements, the difference in the two single test results isexpressed as a percentage of the arithmetic mean of the two testresults (in absolute units).10.6 In addition to the standard precision calculation proce-dure as described above, an analysis of variance w
47、as conducted(a three-factor ANOVA with laboratories, technicians, anddays) to give supplementary information as to the partition ofthe total variation among the three factors. Table 2 gives theresults of that analysis where the percent of the total variationfor the three factors is given to the near
48、est 0.1 %. For tireweight, diameter, and width, 100 % of the variation (to 0.1 %)is the laboratory-to-laboratory component. Tread radius isessentially in this category also. Section width and tread arcwidth have a substantial technician-to-technician component.Durometer hardness (which is a visco-el
49、astic or time dependentmeasurement of modulus) has all three components contribut-ing to the total variation.10.7 This precision evaluation program had an inadequatenumber of laboratories for an in-depth evaluation of the testing7Supporting data for the precision evaluation program of this method have beenfiled at ASTM International Headquarters and may be obtained by requestingResearch Report RR: F09 1001.FIG. 10 Tread Arc Width MeasurementF150205e14precision. The precision results are only a first order estimateand future precision evaluation programs should
