1、Designation: F 1806 97 (Reapproved 2001)e1Standard Practice forTire Testing OperationsBasic Concepts and Terminologyfor Reference Tire Use1This standard is issued under the fixed designation F 1806; the number immediately following the designation indicates the year oforiginal adoption or, in the ca
2、se 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.e1NOTEEditorial corrections were made throughout the document in December 2001.1. Scope1.1 This pract
3、ice presents some basic concepts for tiretesting and a standard set of terms relating to the use ofreference tires frequently used for comprehensive tire testingprograms. The tests may be conducted in a laboratory onvarious dynamometer wheels or other apparatus as well as atoutdoor proving ground fa
4、cilities. The overall objective of thispractice is to develop some elementary principles for suchtesting and standardize the terms used in these operations. Thiswill improve communication among those conducting thesetests as well as those using the results of such testing.1.2 In addition to the basi
5、c concepts and terminology, astatistical model for tire testing operations is also presented inAnnex A1. This serves as a mathematical and conceptualfoundation for the terms and other testing concepts; it willimprove understanding. The annex can also serve for futureconsultation as this practice is
6、expanded to address additionalaspects of the testing process.1.3 This overall topic requires a comprehensive treatmentwith a sequential or hierarchical development of terms withsubstantial background discussion. This cannot be accommo-dated in Terminology F 538.1.4 This standard does not purport to
7、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 Standards:E 1136 Spec
8、ification for a Radial Standard Reference TestTire2F 538 Terminology Relating to the Characteristics and Per-formance of Tires3F 1082 Practice for TiresDetermining Precision for TestMethod Standards3F 1650 Practice for Evaluating Tire Traction PerformanceData Under Varying Test Conditions33. Signifi
9、cance and Use3.1 Tire testing operations usually consist of a sequence oftests that involve special “reference” tires in addition to thecandidate tires being evaluated for their performance charac-teristics. Reference tires serve as an “internal benchmark”which may be used to adjust for variation in
10、 test results to giveimproved comparisons among the candidate tires. Numerousapproaches have been adopted using different terminology forsuch testing. This causes confusion and the purpose of thispractice is to standardize some of the elementary concepts andterminology on this topic.4. Summary of th
11、e Practice4.1 Elementary testing concepts, terms, and definitions aredeveloped in hierarchical or sequential order beginning withbasic testing operations. Each definition may be accompaniedby a specific discussion or expanded text section appropriate togeneral definitions. Many of the terms could be
12、 defined asadjectives; however, as recommended by ASTM policy, theword “tire” is included in each definition avoiding the compli-cation of defining adjectives. The definitions apply equally toitems or objects other than tires.5. Basic Testing Concepts and Terms5.1 Background on Testing:5.1.1 Despite
13、 the adoption of standardized testing proce-dures, test result variation influences data generated in any typeof testing. As outlined in Annex A1, there are two maincategories: 1 variation inherent in the production process fora group of nominally identical objects or tires and 2 variationdue to the
14、 measurement operation. Each of these two sourcesmay be further divided into two types of variation; 1systematic or bias variation (the variation causing one labora-tory to be consistently different from another laboratory) and2 random error variation. Both types can exist simultaneouslyfor either o
15、f the main categories.5.1.2 Random variation can be reduced to a low level byappropriate replication and sampling procedures, but bias1This practice is under the jurisdiction of Committee F09 on Tires and is thedirect responsibility of Subcommittee F09.94 on Terminology.Current edition approved May
16、10, 1997. Published April 1998.2Annual Book of ASTM Standards, Vol 04.03.3Annual Book of ASTM Standards, Vol 09.02.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.variation cannot be so reduced. Bias variation can be reducedor elimin
17、ated by the appropriate use of reference objects ortires. This is the major rationale for their use in testingoperations (see Annex A1).5.1.3 Bias variation can also be reduced or eliminated bycomprehensive programs to sort out causes of such perturba-tions and eliminate these causes.5.2 Elementary
18、Testing Terms:5.2.1 test (or testing), na procedure performed on anobject (or set of nominally identical objects) using specifiedequipment that produces data unique to the object (or set).5.2.1.1 DiscussionTest data are used to evaluate or modelselected properties or characteristics of the object (o
19、r set ofobjects). The scope of testing depends on the decisions to bemade for any program, and sampling and replication plans (seedefinitions below) need to be specified for a complete programdescription.5.2.2 test tire, na tire used in a test.5.2.3 test program, nan ordered series of tests groupedt
20、ogether using a predefined plan.5.2.3.1 DiscussionA test program may include multipletest repetitions over an extended time period.5.2.4 test tire set, none or more test tires as required bythe test equipment or procedure, to perform a test, therebyproducing a single test result.5.2.4.1 DiscussionTh
21、e four nominally identical tires re-quired for vehicle stopping distance testing constitute a test tireset. In the discussion below where the test tire is mentioned, itis assumed that test tire set may be substituted for test tire, if atest tire set is required for the testing.5.2.5 candidate tire,
22、na test tire that is part of a testprogram.5.2.5.1 DiscussionThe term “candidate object” may beused in the same sense as candidate tire.5.2.6 candidate tire seta set of candidate tires.5.3 Tire testing may be divided into two major categories:5.3.1 local testing, ntesting conducted at one laboratory
23、or test site for the purpose of comparing a number of candidatetires for selected characteristic properties.5.3.1.1 DiscussionA tire manufacturers internal develop-ment programs and proving ground testing conducted by acontract testing organization to compare commercial markettires are two examples
24、of local testing.5.3.2 global testing, ntesting conducted at two or morelaboratories or test sites for the purpose of comparing candidatetire performance at each location for selected characteristicproperties.5.3.2.1 DiscussionProducer-user testing or interlabora-tory comparisons for such properties
25、 as rolling resistance,endurance, or high speed dynamometer wheel performance areexamples of global testing.5.4 sample, na selected number of n test objects thataccurately represent the lot or population of interest.5.4.1 DiscussionA lot is a finite number of objects such asa limited period of tire
26、production at a given facility or aselected number of tires of a particular commercial markettype. A population is the collection (or potential collection) ofall objects produced by a given process or operation.5.5 sampling, vthe act of selecting samples.5.5.1 DiscussionThe primary purpose of sampli
27、ng is thereduction of random production process variation. See AnnexA1 for details.5.6 replicate, neither (1) an individual test object from asample of n objects or (2) one of m individual test values for atest object.5.6.1 DiscussionEach test object of a set of replicates isnominally identical to a
28、ll other objects from that particularsource. Nominally identical implies that in long run testing allobjects would give essentially identical average test values.5.7 replication, vthe act of selecting and testing a numberof replicates.5.7.1 DiscussionThe primary purpose of replication is thereductio
29、n of random measurement variation. See Annex A1(A1.3.6) for additional discussion on types of replication.6. Reference Tire Concepts and Terms6.1 In this section a basic term, reference tire, is defined. Anumber of terms, each describing a special type of referencetire, are derived from the basic te
30、rm. Reference tires usuallyhave special characteristics unique to a particular test program.However, for some testing programs the same reference tiremay be used for more than one purpose.6.1.1 reference tire, na special tire included in a testprogram; the test results for this tire have significanc
31、e as a basevalue or internal benchmark.6.1.2 There are two types of reference tires or objects thatmay be used in any test program.6.1.2.1 Type 1 (reference tire), ntires subject to produc-tion, composition, and often, performance specifications; theyare designed to have minimal variation and to be
32、stable in theircharacteristic properties for an extended period of time.6.1.2.2 Type 2 (reference tire), ntires appropriately se-lected from a lot by a process that ensures minimal variationcharacteristic properties for the duration of any test program.6.1.3 DiscussionType 2 reference tires may be s
33、elected onan ad hoc basis and when the test program is complete they areno longer considered as reference objects.6.1.4 control tire, na reference tire used in a specifiedmanner throughout a test program.6.1.4.1 DiscussionA control tire may be of either type andtypical tire use is the reference (con
34、trol) tire in Practice F 1650that provides algorithms for correcting (adjusting) test data forbias trend variations (See Practice F 1650 and Annex 1).6.1.5 surface monitoring tire, na reference tire used toevaluate changes in a test surface over a selected time period.6.1.6 standard reference test t
35、ire (SRTT), na tire thatmeets the requirements of Specification E 1136, commonlyused as control tire or a surface monitoring tire.6.1.6.1 DiscussionThis is a Type 1 reference tire.6.1.7 witness tire, na reference tire with an extendedperiod of stability for specified characteristic properties.6.1.7.
36、1 DiscussionA Type 1 reference tire is typical forthis application.6.1.8 master set, na selected group of witness tires, eachdifferent test response characteristics to provide a range ofvalues for the measured property or properties.6.1.8.1 DiscussionA master set is frequently tested toF 18062determ
37、ine if a test device is functioning in a normal or intendedmanner. If certain known or expected relationships are notfound among the witness tires constituting the set, remedialaction is required for the testing equipment. Master sets arefrequently used for global testing.6.1.9 test matrix, na group
38、 of candidate tires usuallyspecified reference tires; all tests are normally conducted in onetest program.6.1.9.1 DiscussionA test matrix may be used in either alocal or global test program. See also candidate tire set.6.1.10 calibration tire, na witness tire designed to providea fixed or known test
39、 value for selected properties.6.1.10.1 DiscussionCalibration tire test results can beused as standard values to determine acceptability of laboratoryor test site performance. If a specified performance level is notfound, certain instrument adjustments may be made to com-pensate for unavoidable bias
40、es in interlaboratory or between-site programs.7. Evaluating Testing Precision7.1 As indicated in Annex A1, there are two categories ofvariation: production process and measurement. Each of thesemay in turn have two subclassifications: basis deviations andrandom deviations. The potential effect of a
41、ll these sources canexert a profound influence on the variability of test data. Thepresence of these sources is the rationale for using referencetires and for designing comprehensive testing programs withappropriate replication to reduce the effect of such variations.7.2 Evaluating PrecisionSpecial
42、programs to evaluate themagnitude of variability for any routine or special test opera-tions are part of the effort to reduce variability and improve testprecision. Precision is defined in Practice F 1082 as “a mea-surement (testing) concept that expresses the ability to generatetest results that ag
43、ree with each other in absolute magnitude.”The parenthetical word “testing” is added to this definition forthis purposes of this practice to indicate that is is the overalltesting process, which includes sampling and replication, thatshould be considered when discussing precision.7.2.1 For local tes
44、ting, this action usually consists of appro-priate sampling and replication plans and the evaluation of“test-to-test” variation for candidate tires. With a “test-to-test”standard deviation (or variance) obtained under the appropriateconditions, decisions on statistical (and technical) differencesbet
45、ween candidate tires can be made for a program at anyspecific location. For global testing, programs can be organizedto evaluate another “test-to-test” standard deviation, where thisnow applies to between-lab as well as to between-test com-parisons.7.3 Repeatability and Reproducibility:7.3.1 The ter
46、ms repeatability and reproducibility are fre-quently used when discussing testing and the results of testingprograms. Some interpretations of these terms are differentthan the standard definitions given in Practice F 1082.7.3.1.1 repeatability, nan established value, below whichthe absolute differen
47、ce between two “within-laboratory” or“within test site” test results may be expected to lie, with aspecified probability (Practice F 1082).7.3.2 DiscussionThe two test results are obtained with thesame method on nominally identical test materials under thesame conditions (same operator, apparatus, l
48、aboratory, loca-tion, and specified time period), and in the absence of otherindications, the specified probability is 0.95 (that is, 95 %). Theestablished value also may be called a “critical difference.”7.3.2.1 reproducibility, nan established value, belowwhich the absolute difference between two
49、“between-laboratory” or “between test site” test results may be expectedto lie, with a specified probability (Practice F 1082).7.3.3 DiscussionThe two test results are obtained with thesame method on nominally identical test materials underdifferent conditions (different laboratories, locations, operators,apparatus, and in a specified time period), and in the absence ofother indications, the specified probability is 0.95 (that is,95 %). The essential characteristic of reproducibility is thevariability of test results among typical lab
