1、Designation: D6085 97 (Reapproved 2011)Standard Practice forSampling in Rubber TestingTerminology and BasicConcepts1This standard is issued under the fixed designation D6085; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、 of last revision. A 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 practice covers a standardized terminology andsome basic concepts for testing and sampling across the broadra
3、nge of chemical and physical testing operations characteristicof the rubber and carbon black manufacturing industries.1.2 In addition to the basic concepts and terminology, amodel for the test measurement process is given in Annex A1.This serves as a mathematical foundation for the terms andother te
4、sting concepts. It may also find use for further devel-opment of this practice to address more complex samplingoperations.1.3 This general topic requires a comprehensive treatmentwith a sequential or hierarchical development of terms withsubstantial background discussion.Anumber of ancillary termsar
5、e also given that make for a more self-contained document.This cannot be accommodated in Terminology D1566.1.4 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 establish appro-priate safety a
6、nd health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1566 Terminology Relating to RubberD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesD5406 Prac
7、tice for RubberCalculation of Producers Pro-cess Performance Indexes3. Terminology3.1 Definitions:3.2 Despite the adoption of standard test methods, test resultvariation influences the data generated in all testing programs.As outlined in Annex A1, there are two main categories: (1)variation inheren
8、t in the production process for a material orclass of objects, and (2) variation due to the measurementoperation itself. Each of these two sources may be furtherdivided into two types of variation: (1) systematic or biasvariation, and (2) random error variation. Both types can existsimultaneously fo
9、r either of the main categories.3.3 Random variation can be reduced to a low level byappropriate replication and sampling procedures, but biasvariation cannot be so reduced. However, bias variation can bereduced or eliminated by comprehensive programs to sort outthe causes of such perturbations and
10、eliminate these causes.3.4 Elementary Testing Terms:3.4.1 lot, na specified mass of material or number ofobjects, generated by an identifiable process, with a recognizedcomposition or property range.3.4.1.1 DiscussionA lot is frequently generated by acommon production process in a restricted time pe
11、riod andusually consists of a finite size or number. A lot may be afractional part of a population (Interpretation 2 of population).3.4.2 material, na specific entity that exists in bulk form(solid, powder, liquid).3.4.2.1 DiscussionA material may or may not be homo-geneous. Typical materials are in
12、dividual rubbers, compounds,accelerators, carbon blacks, etc.3.4.3 object, na discrete item or piece with a specifiedshape and size.3.4.3.1 DiscussionUsually an object is an entity that isready for testing.Atypical object is an o-ring, dumbbell, pellet,or hose assembly.3.4.4 object class (or class o
13、f objects), na number ofobjects, with a recognized property range, generated by acommon process, the objects are usually characterized by thevalue(s) of a unique property.3.4.4.1 DiscussionIn any testing program the phrase “arecognized property range” implies that the tester is aware ofthe approxima
14、te value of this range. At one extreme, thisrecognized range may denote “essentially identical propertyvalues;” at the opposite extreme this recognized range maydenote “widely varying property values.” The range applies to1This practice is under the jurisdiction of Committee D11 on Rubber and is the
15、direct responsibility of Subcommittee D11.16 onApplication of Statistical Methods.Current edition approved May 1, 2011. Published July 2011. Originally approvedin 1997. Last previous edition approved in 2006 as D6085 97 (2006). DOI:10.1520/D6085-97R11.2For referenced ASTM standards, visit the ASTM w
16、ebsite, 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United S
17、tates.both materials and object classes, and testing programs willdiffer in regard to the extent of variation under consideration.3.4.5 population, na generic term used in testing opera-tions that may refer to any one of the following: (1) a singleobject or a very limited mass of material, (2) a fin
18、ite (but large)number of objects or large mass of material, or (3) a hypo-thetical infinite number of objects or mass of material; all threeinterpretations imply that the objects or material are generatedby some identifiable process and have recognized propertyrange.3.4.5.1 DiscussionTesting program
19、s may vary from avery limited focus of attention (Interpretation 1) to an extremeor broad focus of attention (Interpretation 3). The focus ofattention is determined by the testing and the samplingprogram.3.4.6 test (or testing), na technical procedure performedon a material or object class using spe
20、cified equipment thatproduces data unique to the material or object class; the dataare used to evaluate or model selected properties or character-istics.3.4.6.1 DiscussionTesting can be conducted on a narrowor broad basis, depending on the decisions to be made for anyprogram. Sampling and replicatio
21、n plans (see 3.5) need to bespecified for a complete program description. Testing may bedivided into two major categories:3.4.6.2 global testing, ntesting that is conducted at two ormore locations or laboratories for the purpose of comparingmaterials or object classes at each location for selectedch
22、aracteristic properties.3.4.6.3 DiscussionTypical global testing applications areproducer-user testing and interlaboratory comparisons such asprecision evaluation. These may be conducted on a worldwidebasis.3.4.6.4 local testing, ntesting that is conducted at onelocation or laboratory for the purpos
23、e of comparing a numberof materials or object classes for some selected characteristicproperties.3.4.6.5 DiscussionQuality control and internal develop-ment programs are typical local testing.3.5 Sampling and Related Testing Terms:3.5.1 random sample, none of a sequence of samples (orsub-samples) ta
24、ken on a random basis from a lot or population.3.5.2 replicate, na generic term used in testing operationsthat denotes one of a selected number of fractional parts orobjects taken from a sample; each fractional part or object istested.3.5.3 replication, nthe act of selecting replicates.3.5.3.1 Discu
25、ssionThe primary purpose of replication isthe reduction of random test measurement variation. SeeAnnex A1 for additional discussion on types of replication.3.5.4 sample, na small fractional part of a material or aspecified number of objects that are selected from a lot fortesting, inspection, or spe
26、cific observations of particular char-acteristics.3.5.4.1 DiscussionA sample may be obtained from thecombination of a series of incremental parts, each part obtainedin one step of a particular sampling process (see sub-sample).3.5.5 sampling, nthe act of selecting samples of any type.3.5.5.1 Discuss
27、ionThe goals of sampling are (1) an accu-rate or representative evaluation of the characteristic propertiesof the lot or population, and (2) an accurate estimate of thevariation of properties within the lot or population.3.5.6 sub-sample, none of a sequence of intermediatefractional parts or interme
28、diate sets of objects taken from a lotor population that usually will be combined in a prescribedprotocol to form a sample.3.5.7 systematic sample, none of a sequence of samples(or sub-samples), each taken from a particular location orregion of a lot or population according to a prescribed plan; the
29、usual goal is to determine if the lot or population is homoge-neous.3.5.7.1 DiscussionNon-homogeneity may be of a randomnature or it may be systematic (variation), which is frequentlyreferred to as “stratification.”3.5.8 test piece, nsee test specimen, the preferred term.3.5.9 test portion, nsee tes
30、t sample, the preferred term.3.5.10 test sample, nthat part of a sample of any typetaken (usually with a prescribed blending or other protocol) forchemical or other analytical testing.3.5.10.1 DiscussionA test sample may be a replicate or itmay be subdivided into n replicates; these n replicates are
31、frequently called “laboratory samples.” Test samples are typi-cally drawn to represent materials such as rubbers, pigments,chemicals, etc.3.5.11 test specimen, nan object (appropriately shapedand prepared) taken from a sample for physical or mechanicaltesting.3.5.11.1 DiscussionA test specimen is us
32、ually a replicate.Test specimens are typically prepared by a rubber processing(and curing) operation to evaluate characteristic properties ofdevelopment compounds and the compounds used in manufac-tured rubber products. They may also be manufactured rubberparts such as o-rings, motor mounts, etc.3.6
33、 Testing Variation TermsAnnex A1 defines a numberof test data variation terms (see A1.4). Some additional terms,as given below, apply to typical development testing as well asquality control and quality assurance.3.6.1 common cause variation, nthat residual variationinherent in any process that (1)
34、is operating in a state ofstatistical control, and (2) is operating at some recognized orascertained level of technological competence (PracticeD5406).3.6.2 special cause variation, nthat variation attributableto certain specific or assignable sources that have been (or maybe) discovered through an
35、investigation of the process (PracticeD5406).3.6.2.1 DiscussionBoth common and special cause varia-tion may contain bias as well as random variation components.A synonym for common cause variation is non-assignablevariation; a synonym for special cause variation is assignablevariation.3.6.3 total pr
36、ocess variation, na range, along the mea-sured property scale, defined as six times the standard devia-tion (determined under specified process conditions); thevariation may contain either common or combined commonand special cause sources (Practice D5406).D6085 97 (2011)23.6.3.1 DiscussionAlthough
37、this is defined in terms ofquality control operations, it applies equally to general testing.For this general testing, the “process” and the “standarddeviation” refer to the total (testing and sampling) operation.4. Significance and Use4.1 This practice provides a standardized terminology and arevie
38、w of some basic concepts for elementary sampling andtesting. These operations are important for: (1) local orintralaboratory testing that generally applies to internal qualitycontrol, process capability or performance evaluation, as wellas development programs, and (2) global or interlaboratorytesti
39、ng that applies to producer-user and other testing programsthat have industry-wide or worldwide scope. It is recognizedthat certain test methods may require more detailed andspecialized sampling operations than the generic ones asdescribed herein. These specialized sampling proceduresshould utilize,
40、 as far as possible, the basic concepts as given inthis practice.4.2 This practice provides a list of terms and concepts thatmay be used in numerous test methods used by CommitteesD11 and D24. It improves communication among those thatconduct testing in the rubber and carbon black manufacturingindus
41、tries and those that use such testing and test results fortechnical decisions.5. Elementary Sampling Concepts5.1 The purpose of testing is the production of test data to beused to make technical decisions. Test data are the end result ofa three-step process: (1) test program organization, (2) sam-pl
42、ing, and (3) testing. Test data quality depend on the organi-zation and the sampling for any program.5.2 Types of Sampling Plans:5.2.1 Intuitive SamplingThis is a plan organized on thebasis of the developed skill and judgment of the sampler.General information of the lot or population as well as pas
43、tsampling and testing experience are used to make samplingdecisions. The decisions made on the data generated by such aplan are based on a combination of the skill and experience ofthe tester buttressed by limited statistical conclusions. Strictprobabilistic conclusions usually are not warranted.5.2
44、.2 Statistical SamplingThis is based on strict statisticalsampling and such a plan provides the basis for authenticprobabilistic conclusions. Hypothesis testing may be con-ducted, inferences drawn, and predictions made about futuresystem or process behavior. Usually a large number of samplesare need
45、ed if the significance of small differences is ofimportance. Conclusions from this type of sampling usually arenot controversial. The statistical model chosen is important.When the number of samples required is large and this imposesa testing burden, hybrid plans using some simplifying intuitiveassu
46、mptions are frequently employed.5.2.3 Protocol SamplingThese are specified plans usedfor decision purposes in a given situation. Regulations (of theprotocol) usually specify the type, size, frequency, and periodof sampling in addition to the test methods to be used and otherimportant sampling issues
47、. The protocol may be based on acombination of intuitive and statistical considerations. Testingfor conformance with producer-user specifications for com-mercial transactions is typical for this approach.5.3 Ensuring the Quality of Samples and Testing:5.3.1 Only the most elementary sampling issues a
48、re ad-dressed in this section. For more detailed information, standardtexts on sampling and sampling theory should be consulted.Well defined sampling operations must be conducted to ensurethat high quality samples are used for any testing program.Quality is ensured when the samples are drawn in acco
49、rdancewith a prescribed procedure. This ensures that they accuratelyrepresent the lot or population. Such issues as sample homo-geneity (or unintended stratification) and sample stability(conditioning or storage changes in the sample prior to testing)must be addressed. The sampling procedures, holding time,and other handling operations should be well documented. Thetest methods used for any program should be stable or in a stateof statistical control and have demonstrated sensitivity as wellas good precision in regard to the measured para
