1、Designation: F 762 94 (Reapproved 2000)e1Standard Test Method forDetermining Change in Groove (or Void) Depth WithDistance Traveled for Passenger Car Tires1This standard is issued under the fixed designation F 762; the number immediately following the designation indicates the year oforiginal adopti
2、on or, in the case of 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.e1NOTESources for definitions in Section 3 were editorially added in May 2000.1. Scop
3、e1.1 This test method covers a procedure to be used to obtaindata for determining the changes in tire tread depth over anyspecified course and test period.1.2 The tire tread depth loss data obtained according to theprocedures for this test method may be used to calculate tiretread wear by way of the
4、 procedures described in PracticeF 1016.1.3 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of th
5、e 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 Standards:F 421 Test Method for Measuring Groove and Void Depthin Passenger Car Tires2F 457 Test Method for Speed and
6、Distance Calibration of aFifth Wheel Equipped With Either Analog or DigitalInstrumentation2F 538 Terminology Relating to the Characteristics andPerformance of Tires2F 1016 Practice for Tire Treadwear Data Analysis2F 1502 Test Method for Static Measurements on Tires forPassenger Cars, Light Trucks, a
7、nd Medium Duty Vehicles23. Terminology3.1 Definitions:3.1.1 break-in, none or more periods of initial standard-ized tire operation during which tire is brought to the statewhich will lead to more consistent test results. (F 538)3.1.2 element, nan isolated (totally bounded by void)projection. (F 538)
8、3.1.3 groove, na void that is relatively narrow comparedto its length. (F 538)3.1.4 groove (void) average depth, nthe average depth ofall groove depth measurements in a single groove. (F 538)3.1.5 groove (void) depth, L, na measurement of theperpendicular distance from a real or calculated reference
9、 planedefined by edges of two adjacent ribs or elements to the lowestpoint of contact in the groove (void). (F 538)3.1.6 irregular wear, na type of treadwear characterizedby substantial variations of tread loss both from projection toprojection and frequently from point to point on a givenprojection
10、. (F 538)3.1.7 measurement interval, nthe distance travelled, inkilometres (miles), between two successive groove (void)depth measurements. (F 538)3.1.7.1 DiscussionA specified number of test cycles willconstitute a measurement interval. If a tire rotation plan isspecified, the measurement interval
11、shall include equal dis-tance on each specified wheel position for each tire testspecimen. More frequent measurements may be made ifdesired. The number of measurement intervals should becompatible with the tire rotation plan to result in a logical basisfor data interpretation.3.1.8 projection, na pa
12、vement contacting area of the treadband, bounded by void. (F 538)3.1.9 rib, na continuous circumferential projection.(F 538)3.1.10 rotation plan, n in tire testing, the scheduledchange of wheel positions for all tires on a vehicle, andbetween vehicles in a convoy, and scheduled change of vehicleposi
13、tion in a convoy during a road test as appropriate. (F 538)3.1.10.1 DiscussionTest tires should occupy each positionon the vehicle for the same number of cycles. A tire rotationplan may be designed for each test in accordance with therequirement of the test program.3.1.11 test cycle, nin tire testin
14、g, one complete circuit ofthe specified test course. (F 538)3.1.12 tread depth average, n in a single tire, the averageof all tire groove (void) depth measurements.3.1.13 void, na volume (in the tread band) defined by thelack of rubber; the depth dimension of the volume may vary1This test method is
15、under the jurisdiction of ASTM Committee F09 on Tiresand is the direct responsibility of Subcommittee F09.30 on Laboratory (Non-Vehicular) Testing.Current edition approved Dec. 15, 1994. Published February 1995. Originallypublished as F 762 82. Last previous edition F 762 88.2Annual Book of ASTM Sta
16、ndards, Vol 09.02.1Copyright ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.from point to point in (on) the tread band. (F 538)4. Summary of Test Method4.1 The tire test procedure is carried out by repeatedlydriving one or more test vehicles over a specified test course
17、.All tires on each test vehicle are of the same tire sizedesignation: duplicate tires are mounted on each axle. Abreak-in period prior to the measurement program is optional.The tires may be rotated among wheel positions after comple-tion of a specified number of runs over the test course. Driversma
18、intain the same position in the convoy; the vehiclesposition in the convoy is rotated uniformly.4.2 The test consists of a predetermined number of roadtesting cycles. Groove (void) depth measurements are madeafter completion of a specified number of test cycles.4.3 The wear rate may by calculated in
19、 a number of ways(see Practice F 1016).5. Significance and Use5.1 The test data obtained with this test method may be usedto compare the performance of various tires for the conditionsunder which they were tested.5.2 This test method is suitable for a variety of qualityassurance, research, and devel
20、opment purposes, when tires areto be compared during a single series of tests. The proceduredescribed may not be suitable for regulatory statutes orspecification acceptance because the values obtained may notagree, or correlate either in rank order or absolute tread wearperformance level, with value
21、s obtained on other road sur-faces, or on the same surface after additional wear, under otherenvironmental conditions, on other test vehicles, or with resultsobtained by other test procedures.6. Interferences6.1 Vehicles of different types can influence test results.When involved in comparison testi
22、ng, avoid mixing of vehicleswith significantly different drivelines or suspensions.7. Apparatus7.1 Test Vehicle Any vehicle compatible with test loadand tire dimensions.7.2 Rims, of design rim width + 0.5, 0.0 in. for the test tireas recommended by the Tire and Rim Association (T tire; tire groove d
23、epth loss; tire test; tripsheetF 7623The American Society for Testing and Materials takes no position respecting the validity of any patent rights asserted in connectionwith any item mentioned in this standard. Users of this standard are expressly advised that determination of the validity of any su
24、chpatent rights, and the risk of infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invit
25、ed either for revision of this standard or for additional standardsand should be addressed to ASTM Headquarters. Your comments will receive careful consideration at a meeting of the responsibletechnical committee, which you may attend. If you feel that your comments have not received a fair hearing
26、you should make yourviews known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above address or at610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website (www.astm.org).F 7624
