1、Designation: F2251 13Standard Test Method forThickness Measurement of Flexible Packaging Material1This standard is issued under the fixed designation F2251; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、 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 test method covers the measurement of thickness offlexible packaging materials using contact micrometers.1.2 The Precision and
3、Bias statement for this test methodwas developed using both handheld and bench top micrometerswith foot sizes ranging from 4.8 to 15.9 mm (316 to58 in.).1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be e
4、xact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of t
5、he 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 Referenced Documents2.1 ASTM Standards:2D374 Test Methods for Thickness of Solid Electrical Insu-lation (Withdrawn 2013)3D5947 Test Methods for Ph
6、ysical Dimensions of SolidPlastics SpecimensD6988 Guide for Determination of Thickness of Plastic FilmTest SpecimensE171 Practice for Conditioning and Testing Flexible BarrierPackagingE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 ANSI/ASQ Standar
7、ds:4ANSI/ASQC Z1.4 Sampling Procedures and Tables for In-spection by AttributesANSI/ASQC Z1.9 Sampling Procedures and Tables for In-spection by Variables3. Terminology3.1 Definitions:3.1.1 bench micrometertabletop measurement system us-ing a dead weight or spring.3.1.2 footthe moving component of th
8、e micrometer thatcomes in contact with the sample.4. Significance and Use4.1 This test method provides a means for measuring athickness dimension. Accurate measurement of thickness canbe critical to meeting specifications and characterizing process,product, and material performance.4.2 This test met
9、hod does not address acceptability criteria.These need to be jointly determined by the user and producerof the product. Repeatability and reproducibility of measure-ment is shown in the Precision and Bias section. Attentionshould be given to the inherent variability of materials beingmeasured as thi
10、s can affect measurement outcome.5. Apparatus5.1 Mechanical gage, suitable for measuring thickness:5.1.1 The thickness gage may be either a bench or hand-heldmechanical model.5.1.2 The gage should be capable of accurately measuring inincrements of 2.5 m (0.0001 in.).5.1.3 The foot size and foot pres
11、sure should be known andidentified. Because of the compressibility of different materialsit is important when comparing results between differentlaboratories that the size of the foot and pressure be the same.Refer to Guide D6988 for further guidance on foot pressures.5.1.4 It is recommended that a
12、calibration be performed onthe apparatus used and certified to a recognized industrystandard such as National Institute of Standards and Technol-ogy (NIST).1This test method is under the jurisdiction of ASTM Committee F02 on FlexibleBarrier Packaging and is the direct responsibility of Subcommittee
13、F02.20 onPhysical Properties.Current edition approved Aug. 1, 2013. Published October 2013. Originallyapproved in 2003. Last previous edition approved in 2008 as F2251 03 (Reap-proved 2008). DOI: 10.1520/F2251-13.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Cu
14、stomer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from American National Standards Instititute (ANSI) 2
15、5 W. 43rd St.,4th Floor, New York, NY 10036.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1NOTE 1Test Methods D5947 and D374 give guidance on methods forchecking calibration and parallelism.6. Sampling6.1 The number of samples tested
16、 should be adequate to bepredictive of performance. Caution should be taken wheneliminating samples with defects as this can bias results.6.2 SeeANSI/ASQC Z1.4 or Z1.9 for guidance on samplingplans and practices.7. Conditioning7.1 Conditioning of the samples will depend on the materialunder evaluati
17、on. If conditioning before testing is appropriate,normal, and desirable, refer to Specification E171 for guidance.8. Procedure8.1 Review applicable specifications, drawings, or proce-dures. Specify unit of measure to be used and directions relatedto precision requirements (for example, measure to ne
18、arest0.0001 in., round up or down to nearest 1 m, and so forth).8.2 Clean the micrometer contact area (foot and anvil).8.3 Verify that the micrometer reads 0.0 m (0.00000 in.)when no specimen is present.8.4 Place sample to be measured between the gage foot andanvil. The foot and anvil must be mainta
19、ined in a parallel state.The sample must be placed such that the measurement locationis parallel to the gage foot and anvil. The sample should lay flatand smooth without wrinkles, creases or folds. Material shouldnot be under tension when measured.8.5 Release foot and allow reading to stabilize.8.6
20、Read thickness on gauge readout or face.9. Report9.1 Report the following information:9.1.1 Lot number and source of material, date, time, loca-tion and operator of test and complete identification of mate-rials being tested.9.1.2 Any conditioning of the materials.9.1.3 The apparatus used to measure
21、 the thickness, includ-ing the foot size and foot pressure.9.1.4 Any and all deviations from standard.9.1.5 The sampling plan and number of specimens testedalong with test results should at a minimum include mean,range and standard deviation.10. Precision and Bias10.1 PrecisionA research report5desc
22、ribes a round robinconducted in 2002 in accordance with Practice E691, involvingseven laboratories measuring eight specimens. Ten differentpieces of equipment were used to collect information. Equip-ment used and foot sizes are listed in Table 1. Measurementstaken included use of micrometers in 0.00
23、01 in. divisions.Statistical summaries of repeatability (within a laboratory) andreproducibility (between laboratories) are listed in Tables 2 and3. All test results are expressed in SI units of measure.10.2 Concept of “r” and “R”inTables 2 and 3If Srand SRhave been calculated from a large enough bo
24、dy of data, and fortest results that are averages from three tests on one specimenfor each test result, then the following applies:10.3 Repeatability “r” is the interval representing the criti-cal difference between two test results for the same material,obtained by the same operator using the same
25、equipment on thesame day in the same laboratory. Two test results shall bejudged to be not equivalent if they differ by more than the “r”value for that material.5A research report is available from ASTM International Headquarters. RequestRR:F02-1018.TABLE 1 Description of Equipment used in Round Rob
26、in StudiesNOTE 1Force ranges from instruments are specified from 10 to 150 g.Exceptions include bench top model at 15.875 mm (0.625 in.) rated at 7.3psi with a dead weight load of 1033 g and 6.35 mm (0.25 in.) handheld israted at a force between 600 to 1000 g.Diameter Foot Size,mmFoot Size,in.Type M
27、ake4.7752 0.188 Bench Mitutuoyo4.7752 0.188 Bench Mitutuoyo4.7752 0.188 Bench Mitutuoyo6.35 0.250 Handheld Mitutuoyo6.35 0.250 Bench Mitutuoyo9.525 0.375 Bench Ono Sokki9.525 0.375 Handheld Precision Material9.525 0.375 Handheld Mitutuoyo15.875 0.625 Bench TMITABLE 2 Summary of Interlaboratory Resul
28、ts by Measurement SetPartAvg ThicknessRepeatability,Std Dev, srReproducibility,Std Dev, sR95 % Repeatability,Limit, r95 % Reproducibility,Limit, Rmm mils mm mils mm mils mm mils mm milsG: 0.48 mil PET 0.012954 0.5100 0.001008 0.0397 0.002197 0.0865 0.00282 0.1111 0.006152 0.2422A: 2 mil PE 0.053679
29、2.1133 0.000881 0.0347 0.002691 0.1059 0.00247 0.0971 0.007534 0.2966B: 2.5 mil PET/PE 0.06405 2.5217 0.000489 0.0192 0.001915 0.0754 0.00137 0.0539 0.005361 0.2111H: 2.94 mil Calibration Feeler Gage 0.074083 2.9167 0.001316 0.0518 0.00152 0.0598 0.00369 0.1451 0.004255 0.1675F: 42# Uncoated Medical
30、 Paper 0.090678 3.5700 0.000733 0.0289 0.001943 0.0765 0.00205 0.0808 0.00544 0.2142D: 4.2 mil PET/PE/FOIL/PE 0.10994 4.3283 0.000811 0.0319 0.001966 0.0774 0.00227 0.0894 0.005505 0.2167E: Uncoated 1073B Tyvek 0.143722 5.6583 0.00164 0.0645 0.009781 0.3851 0.00459 0.1807 0.027387 1.0782C: 10 mil EV
31、A/SURLYN/EVA 0.260181 10.2433 0.001222 0.0481 0.002596 0.1022 0.00342 0.1347 0.007268 0.2862Average 0.001069 0.0421 0.004001 0.1575 0.00299 0.1178 0.011204 0.4411F2251 13210.4 Reproducibility “R” is the interval representing thecritical difference between two test results for the samematerial, obtai
32、ned by different operators using different equip-ment in different laboratories, not necessarily on the same day.Two test results shall be judged to be not equivalent if theydiffer by more than the “R” value for that material.10.5 Any judgment in accordance with 10.3 or 10.4 willhave approximately 9
33、5 % (0.95) probability of being correct.10.6 BiasBias gage measures to 0.0736 mm (2.94 mils)per NIST calibration testing. Micrometer measurements col-lected to 0.1 mils precision. Analysis is based upon a 2.9 miltarget. The chart in Fig. 1 does not indicate a consistent bias.11. Keywords11.1 dimensi
34、on; micrometer; thickness measurementTABLE 3 Summary of Interlaboratory Averaged ResultsRepeatability (within a laboratory)standard deviation (sr)0.001069 mm (0.0421 mils)95 % repeatability limit (r) 0.00299 mm (0.1178 mils)Reproducibility (between laboratories)standard deviation (sR)0.004001 mm (0.
35、1575 mils)95 % reproducibility limit (R) 0.011204 mm (0.4411 mils)FIG. 1F2251 133ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the va
36、lidity of any such patent rights, and the riskof 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 co
37、mments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments hav
38、e not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple
39、 copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).F2251 134
