1、Designation: D3636 13a1Standard Practice forSampling and Judging Quality of Solid Electrical InsulatingMaterials1This standard is issued under the fixed designation D3636; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、 last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEChanges were made editorially in April 2014.1. Scope*1.1 This practice covers procedures for obtaining datapertaining to the
3、 quality of a lot of electrical insulating materialand for making a judgement whether the lot meets therequirements of a material specification.1.2 This practice is not intended to define a producersinternal quality control procedures but is designed to determinethe acceptability of all, or some por
4、tion, of a quantity ofelectrical insulating material that is available for inspection bythe user of the material.1.3 This practice is intended to be used in conjunction withan existing material specification that specifies property char-acteristic limits, acceptable quality level (AQL), standard tes
5、tmethods, and specific sampling instructions.1.4 In the absence of a specification as described in 1.3, usethis practice as a guide, after establishment of agreed-uponproperty characteristics, limits, AQL, standard test methods,and specific sampling instructions.1.5 It is intended that this be a pra
6、ctice for inspection byattributes.1.6 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 and health practices and determine the applica-bility of regulatory limita
7、tions prior to use.2. Referenced Documents2.1 ASTM Standards:2E300 Practice for Sampling Industrial Chemicals2.2 Military Standard:MIL-STD-105E Sampling Procedures and Tables for In-spection by Attributes3ANSI/ASQ Z1.4, MIL-STD-1916 Department of DefensePreferred Methods for Acceptance of Product2.3
8、 Other Document:ANSI/ASQC A2 -198743. Terminology3.1 Definitions:3.1.1 acceptance number, nthe maximum allowable num-ber of nonconformities for a given AQL and sample size(lot-sample size).3.1.2 acceptable quality level (AQL), nthe maximumpercent nonconforming which, for purposes of samplinginspecti
9、on, is considered satisfactory as a process average.3.1.3 critical property, na quantitatively measurable char-acteristic which is absolutely necessary to be met if a materialor product is to provide satisfactory performance for theintended use.3.1.3.1 DiscussionIn some situations, specification re-
10、quirements coincide with customer usage requirements. Inother situations, they may not coincide, being either more orless stringent. More stringent sampling (for example, smallerAQL values) is usually used for measurement of characteristicswhich are considered critical. The selection of sampling pla
11、nsis independent of whether the term defect or nonconformity isappropriate.3.1.4 defect, na departure of a quality characteristic fromits intended level, or state, that occurs with a severity sufficientto cause an associated product or service not to satisfy intendednormal, or reasonably foreseeable
12、, usage requirements.3.1.4.1 DiscussionThe terms defect and nonconformityand their derivatives are used somewhat interchangeably in thehistorical and current literature. Nonconformity objectively1This practice is under the jurisdiction of ASTM Committee D09 on Electricaland Electronic Insulating Mat
13、erials and is the direct responsibility of SubcommitteeD09.94 on Editorial.Current edition approved March 1, 2013. Published June 2013. Originallyapproved in 1977. Last previous edition approved in 2013 as D3636 13. DOI:10.1520/D3636-13a.2For referenced ASTM standards, visit the ASTM website, www.as
14、tm.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.3Available from U.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washing
15、ton, DC 20401.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesT
16、his international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade
17、(TBT) Committee.1describes the comparison of test results to specificationrequirements, while the term defect has a connotation ofpredicting the failure of a product or service to perform itsintended function in use. Since this latter connotation is oftenunintended, the term nonconformity is preferr
18、ed in full consen-sus standards. The selection of any sample plan is independentof whether the term defect or nonconformity is appropriate.The term defect may be appropriate for specificationsmutually agreed upon by a producer and a user wherespecific use conditions are clearly understood. Even in t
19、hesecases however, use the term defect with caution and considersubstituting the term nonconformity.For additional comments, see ANSI/ASQC A2-1987 thatalso states: “When a quality characteristic of a product orservice is “evaluated” in terms of conformance to specifica-tion requirements, the use of
20、the term nonconformity isappropriate.”3.1.5 group AQLthe AQL assigned to a group of materialproperties.3.1.5.1 DiscussionSee 5.2 for additional informationabout the meaning of AQL.3.1.6 lot, nan entity of electrical insulating material orproduct which, insofar as is practicable, consists of a single
21、type, grade, class, size, or composition that was manufacturedunder essentially the same conditions and is available to theuser for sampling at one time.3.1.7 lot number, nthe number used by a producer toidentify an entity of electrical insulating material or product.3.1.8 major property, na quantit
22、atively measurable char-acteristic which, if not met, is likely to seriously impair theperformance of a material or product for the intended use.3.1.8.1 DiscussionIn some situations, specification re-quirements coincide with customer usage requirements. Inother situations, they may not coincide, bei
23、ng either more orless stringent. More stringent sampling (for example, smallerAQL values) is usually used for measurement of characteristicsthat are considered important. The selection of sampling plansis independent of whether the term defect or nonconformity isappropriate.3.1.9 minor property, na
24、characteristic which, if not met,is not likely to materially reduce the performance of a materialor product for the intended use.3.1.9.1 DiscussionIn some situations, specification re-quirements coincide with customer usage requirements. Inother situations, they may not coincide, being either more o
25、rless stringent. More stringent sampling (for example, smallerAQL values) is usually used for measurement of characteristicsthat are considered important. The selection of sampling plansis independent of whether the term defect or nonconformity isappropriate.3.1.10 nonconforming unit, na unit of pro
26、duct containingat least one nonconformity.3.1.11 nonconformities per hundred units, na calculatedratio of nonconforming units to the number of units inspected,the quotient being multiplied by 100 (See 3.1.13.)3.1.12 nonconformity, na departure of a quality character-istic from its intended level or
27、state that occurs with a severitysufficient to cause a test result not to meet a specificationrequirement.3.1.13 percent nonconforming, na calculated ratio of non-conforming units to the number of units inspected, the quotientbeing multiplied by 100.3.1.14 rejection number, nthe minimum number of no
28、n-conformities for a given AQL and sample size (lot-sample size)which will subject a lot to rejection.3.1.15 sample, none or more units of product taken froma lot without regard to the quality of the unit. (Also oftentermed lot sample).3.1.16 sample size, nthe number of units of product takento make
29、 up the sample.3.1.16.1 DiscussionThis standard uses only lot samplesizes and not lot sizes since the discriminatory power of anysampling plan is independent essentially of the size of the lot.The sample size selected by the user for a given acceptablequality level (AQL) is optional depending upon t
30、he degree ofprotection desired by the user against the acceptance ofnonconforming lots.3.1.17 test measurement, na quantitative expression ofone value determined for a property of interest by a singleapplication of a specified test procedure.3.1.18 test result, nthe value that expresses the level of
31、 aproperty of the test unit.3.1.18.1 DiscussionA test result is sometimes a single testmeasurement but usually a test result is computed from severaltest measurements.3.1.19 test specimen, na portion of a test unit upon whichone or more test measurements are made.3.1.20 test unit, na fraction of a u
32、nit of product fromwhich one or more test specimens are taken for each property.3.1.20.1 DiscussionIf the unit of product is of insufficientsize to meet the requirements of a testing method: (1) sampleadjacent units of product and aggregate units of product for thetest unit or, (2) obtain a test uni
33、t of sufficient size, andrepresentative of the unit of product, from the producer.3.1.21 unit of product, nan entity of electrical insulatingmaterial or product for inspection to determine its classificationas conforming or non-conforming.3.1.21.1 DiscussionA unit of product is established by theuse
34、r and may or may not be the same as a unit of purchase,supply, production, or shipment. Some examples of a unit ofproduct are:Bag Case ReelBarrel Container RollBin Cop SheetBobbin Drum SkidBox Length SpoolBundle Pad TankCar Pail Tank compartmentCarton Pallet Truckload4. Summary of Practice4.1 Instru
35、ctions are given for obtaining a sample fromwhich specimens are then taken for testing. The test data areD3636 13a12compared to the material specification and a judgement is thenmade as to whether the material meets the requirements of saidmaterial specification.4.2 This practice has been modeled af
36、ter MIL-STD-105E.4.3 In those cases where MIL-STD-105E is determined tobe unacceptable for a specific application or purpose and aform of C=0 sampling is required instead, it is permissible toalternatively apply ANSI/ASQ Z1.4, MIL-STD-1916, or asimilar sampling plan.5. Procedure5.1 General Considera
37、tions:5.1.1 Assemble the lot of electrical insulating material sothat a lot sample is obtained in a manner that will minimizebias in the selection of the units of product that will beinspected. A scheme that offers a good chance of minimizingbias is the assignment of numbers to each unit of product
38、andthen using a table of random numbers to select those units ofproduct from which test units are taken.5.1.2 For a lot of electrical insulating material that is in bulkform (for example, a tank car of powdered resin) take the lotsample from the unit of product in accordance with PracticeE300.5.1.3
39、Take the material to be removed from any unit ofproduct in a random manner. When it is impracticable to meetthis requirement (for example, in the case of long lengths ofmaterial wound onto rolls or large, thick, heavy sheets packedon pallets or skids), economy will dictate the removal ofmaterial fro
40、m the end of a roll, or the top of a pile, etc. in whichcases the selection cannot be described as “random.”5.1.4 Take the necessary amount of material from the testunit so as to meet the specimen requirements of the various testmethods that will be used to evaluate the material.5.1.5 Refer to the m
41、aterial specification for the allowablemaximum elapsed time between the assembly of the lot forinspection and the disposition of the lot. If the materialspecification (or other pertinent document) does not cover thismatter, the maximum allowable time is 30 calendar days.5.1.6 Exercise care to protec
42、t the electrical insulating mate-rial contained in the test unit from which specimens are to beprepared. An example of this protection is packaging in metalfoil or glass containers so as to prevent or minimize contami-nation of the material from the effects of the environment towhich such material i
43、s subjected between sampling and testing.5.1.7 Test units assembled as described above shall bedeemed to be representative of the lot of material beinginspected. Disposition of the lot, or portions thereof will bebased upon the data generated from these test units unlessotherwise agreed upon between
44、 the user and the producer.5.2 Establishing Acceptable Quality Levels:5.2.1 Acceptable quality levels (AQLs) for each critical,major, and minor property shall be as mutually agreed upon bythe producer and the user. It is also acceptable to establishgroup AQLs for given groups of properties. Disclose
45、 theseAQLs in a purchase order, material specification, or in someother document. This standard is not intended to impose limitsupon the risks acceptable to either the user or the producer.5.2.2 When a user designates some specific value of AQLfor a single nonconformity, it indicates that the users
46、accep-tance sampling plan will accept the great majority of the lotssubmitted by the producer if the process average level ofpercent nonconforming in the lots is no greater than thedesignated value of AQL. The preceding statement is also truefor a group AQL value designated for a group of nonconfor-
47、mities.5.2.2.1 The sampling plans of this standard are so arrangedthat the probability of acceptance, at the designated AQL value,depends upon the sample size. For a given AQL, the probabil-ity of acceptance will be generally higher for large sample sizesthan for small sample sizes. The AQL alone do
48、es not describethe user protection for individual lots, but more directly relatesto what a user might expect from a series of lots. Refer to theoperating characteristic curve to determine what protection theuser will have for a specific AQL.5.2.3 The designation of an AQL shall not imply that aprodu
49、cer has the right to knowingly supply any nonconformingunit of product.5.2.4 The values of AQL listed in the accompanying tables(see Section Appendix X1) are known as preferred AQLs. Ifany AQL is designated other than a preferred AQL, these tablesare not applicable.5.3 Sampling Plan Selection:5.3.1 Use the designated AQL and the sample size codeletter from Table 1 to select a sampling plan from Tables 2-22.When no sampling plan is available for a given combination ofAQL and code letter, the table directs the user to a differentcode letter. Use