ASTM F1806-97(2001)e1
(Practice)Standard Practice for Tire Testing Operations—Basic Concepts and Terminology for Reference Tire Use
Standard Practice for Tire Testing Operations—Basic Concepts and Terminology for Reference Tire Use
SIGNIFICANCE AND USE
Tire testing operations usually consist of a sequence of tests that involve special “reference” tires in addition to the candidate tires being evaluated for their performance characteristics. Reference tires serve as an “internal benchmark” which may be used to adjust for variation in test results to give improved comparisons among the candidate tires. Numerous approaches have been adopted using different terminology for such testing. This causes confusion and the purpose of this practice is to standardize some of the elementary concepts and terminology on this topic.
SCOPE
1.1 This practice presents some basic concepts for tire testing and a standard set of terms relating to the use of reference tires frequently used for comprehensive tire testing programs. The tests may be conducted in a laboratory on various dynamometer wheels or other apparatus as well as at outdoor proving ground facilities. The overall objective of this practice is to develop some elementary principles for such testing and standardize the terms used in these operations. This will improve communication among those conducting these tests as well as those using the results of such testing.
1.2 In addition to the basic concepts and terminology, a statistical model for tire testing operations is also presented in Annex A1. This serves as a mathematical and conceptual foundation for the terms and other testing concepts; it will improve understanding. The annex can also serve for future consultation as this practice is expanded to address additional aspects of the testing process.
1.3 This overall topic requires a comprehensive treatment with a sequential or hierarchical development of terms with substantial background discussion. This cannot be accommodated in Terminology F538.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
e1
Designation:F1806–97 (Reapproved 2001)
Standard Practice for
Tire Testing Operations–Basic Concepts and Terminology
for Reference Tire Use
This standard is issued under the fixed designation F 1806; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
e NOTE—Editorial corrections were made throughout the document in December 2001.
1. Scope F 1082 Practice for Tires–Determining Precision for Test
Method Standards
1.1 This practice presents some basic concepts for tire
F 1650 Practice for Evaluating Tire Traction Performance
testing and a standard set of terms relating to the use of
Data Under Varying Test Conditions
reference tires frequently used for comprehensive tire testing
programs. The tests may be conducted in a laboratory on
3. Significance and Use
various dynamometer wheels or other apparatus as well as at
3.1 Tire testing operations usually consist of a sequence of
outdoor proving ground facilities. The overall objective of this
tests that involve special “reference” tires in addition to the
practice is to develop some elementary principles for such
candidate tires being evaluated for their performance charac-
testing and standardize the terms used in these operations.This
teristics. Reference tires serve as an “internal benchmark”
will improve communication among those conducting these
which may be used to adjust for variation in test results to give
tests as well as those using the results of such testing.
improved comparisons among the candidate tires. Numerous
1.2 In addition to the basic concepts and terminology, a
approaches have been adopted using different terminology for
statistical model for tire testing operations is also presented in
such testing. This causes confusion and the purpose of this
Annex A1. This serves as a mathematical and conceptual
practice is to standardize some of the elementary concepts and
foundation for the terms and other testing concepts; it will
terminology on this topic.
improve understanding. The annex can also serve for future
consultation as this practice is expanded to address additional
4. Summary of the Practice
aspects of the testing process.
4.1 Elementary testing concepts, terms, and definitions are
1.3 This overall topic requires a comprehensive treatment
developed in hierarchical or sequential order beginning with
with a sequential or hierarchical development of terms with
basic testing operations. Each definition may be accompanied
substantial background discussion. This cannot be accommo-
by a specific discussion or expanded text section appropriate to
dated in Terminology F 538.
general definitions. Many of the terms could be defined as
1.4 This standard does not purport to address all of the
adjectives; however, as recommended by ASTM policy, the
safety concerns, if any, associated with its use. It is the
word “tire” is included in each definition avoiding the compli-
responsibility of the user of this standard to establish appro-
cation of defining adjectives. The definitions apply equally to
priate safety and health practices and determine the applica-
items or objects other than tires.
bility of regulatory limitations prior to use.
5. Basic Testing Concepts and Terms
2. Referenced Documents
5.1 Background on Testing:
2.1 ASTM Standards:
5.1.1 Despite the adoption of standardized testing proce-
E 1136 Specification for a Radial Standard Reference Test
2 dures,testresultvariationinfluencesdatageneratedinanytype
Tire
of testing. As outlined in Annex A1, there are two main
F 538 Terminology Relating to the Characteristics and Per-
3 categories: [1] variation inherent in the production process for
formance of Tires
a group of nominally identical objects or tires and [2] variation
due to the measurement operation. Each of these two sources
This practice is under the jurisdiction of Committee F09 on Tires and is the
may be further divided into two types of variation; [1]
direct responsibility of Subcommittee F09.94 on Terminology.
systematic or bias variation (the variation causing one labora-
Current edition approved Nov. 2, 2001. Published April 1998.
2 tory to be consistently different from another laboratory) and
Annual Book of ASTM Standards, Vol 04.03.
Annual Book of ASTM Standards, Vol 09.02.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
e1
F1806–97 (2001)
[2]randomerrorvariation.Bothtypescanexistsimultaneously 5.4.1 Discussion—Alotisafinitenumberofobjectssuchas
for either of the main categories. a limited period of tire production at a given facility or a
selected number of tires of a particular commercial market
5.1.2 Random variation can be reduced to a low level by
type. A population is the collection (or potential collection) of
appropriate replication and sampling procedures, but bias
all objects produced by a given process or operation.
variation cannot be so reduced. Bias variation can be reduced
5.5 sampling, v—the act of selecting samples.
or eliminated by the appropriate use of reference objects or
tires. This is the major rationale for their use in testing 5.5.1 Discussion—The primary purpose of sampling is the
reduction of random production process variation. See Annex
operations (see Annex A1).
A1 for details.
5.1.3 Bias variation can also be reduced or eliminated by
5.6 replicate, n—either (1) an individual test object from a
comprehensive programs to sort out causes of such perturba-
sample of n objects or (2) one of m individual test values for a
tions and eliminate these causes.
test object.
5.2 Elementary Testing Terms:
5.6.1 Discussion—Each test object of a set of replicates is
5.2.1 test (or testing), n—a procedure performed on an
nominally identical to all other objects from that particular
object (or set of nominally identical objects) using specified
source. Nominally identical implies that in long run testing all
equipment that produces data unique to the object (or set).
objects would give essentially identical average test values.
5.2.1.1 Discussion—Test data are used to evaluate or model
5.7 replication, v—the act of selecting and testing a number
selected properties or characteristics of the object (or set of
of replicates.
objects). The scope of testing depends on the decisions to be
5.7.1 Discussion—The primary purpose of replication is the
made for any program, and sampling and replication plans (see
reduction of random measurement variation. See Annex A1
definitions below) need to be specified for a complete program
(A1.3.6) for additional discussion on types of replication.
description.
5.2.2 test tire, n—a tire used in a test.
6. Reference Tire Concepts and Terms
5.2.3 test program, n—an ordered series of tests grouped
6.1 In this section a basic term, reference tire, is defined. A
together using a predefined plan.
number of terms, each describing a special type of reference
5.2.3.1 Discussion—A test program may include multiple
tire, are derived from the basic term. Reference tires usually
test repetitions over an extended time period.
have special characteristics unique to a particular test program.
5.2.4 test tire set, n—one or more test tires as required by
However, for some testing programs the same reference tire
the test equipment or procedure, to perform a test, thereby
may be used for more than one purpose.
producing a single test result.
6.1.1 reference tire, n—a special tire included in a test
5.2.4.1 Discussion—The four nominally identical tires re-
program; the test results for this tire have significance as a base
quired for vehicle stopping distance testing constitute a test tire
value or internal benchmark.
set. In the discussion below where the test tire is mentioned, it
6.1.2 There are two types of reference tires or objects that
is assumed that test tire set may be substituted for test tire, if a
may be used in any test program.
test tire set is required for the testing.
6.1.2.1 Type 1 (reference tire), n—tires subject to produc-
5.2.5 candidate tire, n—a test tire that is part of a test
tion, composition, and often, performance specifications; they
program.
are designed to have minimal variation and to be stable in their
5.2.5.1 Discussion—The term “candidate object” may be
characteristic properties for an extended period of time.
used in the same sense as candidate tire.
6.1.2.2 Type 2 (reference tire), n—tires appropriately se-
5.2.6 candidate tire set—a set of candidate tires.
lected from a lot by a process that ensures minimal variation
5.3 Tire testing may be divided into two major categories:
characteristic properties for the duration of any test program.
5.3.1 local testing, n—testing conducted at one laboratory
6.1.3 Discussion—Type2referencetiresmaybeselectedon
or test site for the purpose of comparing a number of candidate
an ad hoc basis and when the test program is complete they are
tires for selected characteristic properties.
no longer considered as reference objects.
5.3.1.1 Discussion—Atire manufacturer’s internal develop-
6.1.4 control tire, n—a reference tire used in a specified
ment programs and proving ground testing conducted by a
manner throughout a test program.
contract testing organization to compare commercial market
6.1.4.1 Discussion—Acontroltiremaybeofeithertypeand
tires are two examples of local testing.
typical tire use is the reference (control) tire in Practice F 1650
5.3.2 global testing, n—testing conducted at two or more
that provides algorithms for correcting (adjusting) test data for
laboratoriesortestsitesforthepurposeofcomparingcandidate
bias trend variations (See Practice F 1650 and Annex 1).
tire performance at each location for selected characteristic
6.1.5 surface monitoring tire, n—a reference tire used to
properties.
evaluate changes in a test surface over a selected time period.
5.3.2.1 Discussion—Producer-user testing or interlabora-
6.1.6 standard reference test tire (SRTT), n—a tire that
tory comparisons for such properties as rolling resistance, meets the requirements of Specification E 1136, commonly
endurance, or high speed dynamometer wheel performance are
used as control tire or a surface monitoring tire.
examples of global testing.
6.1.6.1 Discussion—This is a Type 1 reference tire.
5.4 sample, n—a selected number of n test objects that 6.1.7 witness tire, n—a reference tire with an extended
accurately represent the lot or population of interest. period of stability for specified characteristic properties.
e1
F1806–97 (2001)
6.1.7.1 Discussion—A Type 1 reference tire is typical for 7.3.1 The terms repeatability and reproducibility are fre-
this application. quently used when discussing testing and the results of testing
6.1.8 master set, n—a selected group of witness tires, each programs. Some interpretations of these terms are different
different test response characteristics to provide a range of than the standard definitions given in Practice F 1082.
values for the measured property or properties. 7.3.1.1 repeatability, n—an established value, below which
6.1.8.1 Discussion—A master set is frequently tested to the absolute difference between two “within-laboratory” or
determineifatestdeviceisfunctioninginanormalorintended “within test site” test results may be expected to lie, with a
manner. If certain known or expected relationships are not specified probability (Practice F 1082).
found among the witness tires constituting the set, remedial 7.3.2 Discussion—The two test results are obtained with the
action is required for the testing equipment. Master sets are same method on nominally identical test materials under the
frequently used for global testing. same conditions (same operator, apparatus, laboratory, loca-
6.1.9 test matrix, n—a group of candidate tires usually tion, and specified time period), and in the absence of other
specifiedreferencetires;alltestsarenormallyconductedinone indications,thespecifiedprobabilityis0.95(thatis,95 %).The
test program. established value also may be called a “critical difference.”
6.1.9.1 Discussion—A test matrix may be used in either a 7.3.2.1 reproducibility, n—an established value, below
local or global test program. See also candidate tire set. which the absolute difference between two “between-
6.1.10 calibration tire, n—awitnesstiredesignedtoprovide laboratory” or “between test site” test results may be expected
a fixed or known test value for selected properties. to lie, with a specified probability (Practice F 1082).
6.1.10.1 Discussion—Calibration tire test results can be 7.3.3 Discussion—The two test results are obtained with the
usedasstandardvaluestodetermineacceptabilityoflaboratory same method on nominally identical test materials under
or test site performance. If a specified performance level is not differentconditions(differentlaboratories,locations,operators,
found, certain instrument adjustments may be made to com- apparatus,andinaspecifiedtimeperiod),andintheabsenceof
pensate for unavoidable biases in interlaboratory or between- other indications, the specified probability is 0.95 (that is,
site programs. 95 %). The essential characteristic of reproducibility is the
variability of test results among typical laboratories or test
7. Evaluating Testing Precision
sites.
7.1 As indicated in Annex A1, there are two categories of 7.3.4 Both repeatability and reproducibility are to some
variation: production process and measurement. Each of these degree generic in their definition.Additional information must
may in turn have two subclassifications: basis deviations and be supplied before the terms can be used without ambiguity.
random deviations.The potential effect of all these sources can The most important issue is the between–test result time period
exert a profound influence on the variability of test data. The or frequency; it must be specified.What constitutes a test result
presence of these sources is the rationale for using reference must be defined. Both of these are addressed in Practice
tires and for designing comprehensive testing programs with F 1082. Other details on testing are also needed. It is important
appropriate replication to reduce the effect of such variations. to emphasize two details about repeatability and reproducibil-
ity; (1) both are statistical parameters; defined as 2.833 S,
7.2 Evaluating Precision—Special programs to evaluate the
magnitude of variability for any routine or special test opera- where Sisthestandarddeviationforeitherparametermeasured
in a specified way as outlined in Pr
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.