1、Designation: F2824 10Standard Test Method forMechanical Seal Strength Testing for Round Cups and BowlContainers with Flexible Peelable Lids1This standard is issued under the fixed designation F2824; 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 () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method describes a method for the measure-ment of mechanical seal strength while
3、 separating the entire lid(cover/membrane) from a rigid or semi-rigid round container.1.2 This test method differs from Test Method F88. TestMethod F88 tests a portion of the seal where as this test methodtests the force required to separate the entire lid (cover/membrane) from the container.1.3 Thi
4、s test method is used to determine the continuous andmaximum forces required to separate the lid (cover/membrane)from the container.1.4 This test method uses an angle of pull of 45, howeverother angles of pull may be used provided results are docu-mented noting the used angle of pull and said proced
5、ure isvalidated.1.5 Typical examples of container shapes that could betested using this or a similar method include oval, rectangular,and circular with single or multiple cavities having a sealed lid(cover/membrane). Examples of products packaged in thesetypes of containers are: ready meals, creamer
6、s, coffee, yogurts,household fresheners, chemical and pharmaceutical products,and numerous others not mentioned. However, this testmethod, described within, is specifically for round containers.1.6 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses a
7、re mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.7 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
8、 and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D4332 Practice for Conditioning Containers, Packages, orPackaging Components for TestingE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE6
9、91 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodF17 Terminology Relating to Flexible Barrier PackagingF88 Test Method for Seal Strength of Flexible BarrierMaterials2.2 Other Standard:ANSI/AAMI/ISO 116071 Packaging for Terminally Ster-ilized Medical Devic
10、esPart 1: Requirements for Mate-rials, Sterile Barrier Systems, and Packaging Systems33. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 average seal strengththe sum of the individualforces recorded divided by the total number of those measure-ments. The calculation can be expres
11、sed as the averagebetween the peaks or within the peaks (see Fig. 1).3.1.2 flexibleSee Terminology F17.3.1.3 grip separation ratea function of the test equipmentdesign and angle of peel to achieve the correct peel rate. It isthe actual peel rate of separating the lid (cover/membrane)from the contain
12、er. For this test method, the actual separationrate is 12 in./min (300 mm/min).3.1.4 maximum seal strengththe maximum force mea-sured when separating progressively, under the conditions ofthe test.1This test method is under the jurisdiction of ASTM Committee F02 on FlexibleBarrier Packaging and is t
13、he direct responsibility of Subcommittee F02.20 onPhysical Properties.Current edition approved May 1, 2010. Published June 2010. DOI: 10.1520/F282410.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStand
14、ards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken
15、, PA 19428-2959, United States.3.1.5 peel anglethe angle of the lid (cover/membrane)relative to the container seal surface at all points of removal ofthe lid (cover/membrane) from the container seal surface. Thepreferred angle for this test method is 45 (Fig. 2) but otherangles can be used.3.1.6 pee
16、l linethe line of direction of peel, normally 90to the line beginning at the starting peel point and bisects thecontainer area evenly (see Fig. 2).3.1.7 seal areathe total area of the container which issealed to the lid (cover/membrane) and requires a force toseparate them.3.1.8 starting peel pointt
17、he extended tab provided by thedesign of the lid (cover/membrane).3.1.9 workthe energy required to separate the lid (cover/membrane) from the test container. Typically, this calculationis made by the computer software or can be calculated as thearea under the force-displacement curve.4. Summary of T
18、est Method4.1 The test sample (container) is fastened securely to thetest fixture with the starting peel point (extended tab ifprovided) of the lid (cover/membrane) attached to the grip ofthe force measuring device (load cell). The lid (cover/membrane) is peeled from the container at a constant rate
19、 ofspeed along the peel line of the container and at a 45 angle(other angles are permitted but must be noted and reported withtest results) measured from the sealed surface of the containerand lid (cover/membrane). Forces measured during the test arerecorded and plotted for analysis and reporting.5.
20、 Significance and Use5.1 Test Method F88 has been the standard for the mechani-cal peel strength testing of peelable seals since the 1960s.Normally the testing is run on a portion of the seal. The resultis an actual seal strength picture of that portion of the seal. Thistest method is different in t
21、hat the entire package seal is peeledopen and data collected for the entire sealed area.5.2 This test method is a tool for quality assurance use aswell as performance evaluation of a seal during separation.5.3 With appropriate software, data is collected depictingthe seal strength of the entire leng
22、th of the seal. As a result, itis possible to see seal strength variations, as the seal is peeledapart, thereby evaluating the consistency and uniformity of theseal (see Fig. 1).FIG. 1 Average Seal StrengthF2824 1026. Apparatus6.1 Testing machine of the constant-rate-of-peel type shallbe used.6.2 Th
23、e constant rate of peel between the clamp (grip) andthe sample container shall be maintained at a constant rate of12 6 0.5 in./min (300 6 12.7 mm/min).6.3 There shall be an electronic measuring device (forcegage) capable of taking a sufficient number of readings persecond and compatible with the com
24、puter program such that acontinuous graph of force versus displacement is achieved. It isalso possible to use an analog instrument which inputs to anX-Y plotter to obtain the force versus displacement curve. Aclamp or grip is fastened to the electronic measuring deviceand suitable for holding the li
25、d (cover/membrane) shall be used(see Fig. 1).6.4 There shall be a fixture suitable for securing the samplecontainer in such a position as to cause the lid (cover/membrane) to be peeled at a constant 45 angle during theentire test. Since any movement of the container in the fixturecan affect the valu
26、e obtained by the electronic measuringdevice, the container must be held fast.7. Sampling and Test Specs and Units7.1 Sample size is determined by using an approved statis-tically validated sampling plan.7.2 Sample identification should be made prior to specifictest samples, if necessary. Record the
27、 information such that testresults and anomalies are identifiable back to the individualspecimens.8. Preparation of Apparatus8.1 Apparatus shall be positioned according to manufactur-ers instructions and in a suitable environment for testingconditions.9. Calibration and Standardization9.1 Calibratio
28、n of the force gage shall be verified prior totesting and accurate to 61 % of the full scale of the electronicmeasuring device.9.2 Follow the gage manufacturers procedure for calibra-tion.10. Conditioning10.1 Conditioning of the samples will depend on the mate-rial under evaluation. If conditioning
29、before testing is appro-priate, normal, and desirable, then condition the test specimensat 23 6 2C (73.4 6 3.6F) and 50 6 5 % RH until materialhas reached stabilization. See Practice D4332 for guidance onconditioning practices.11. Procedure11.1 Verify calibration of the force-measuring device priort
30、o proceeding with the test. See 9.2.FIG. 2 Peel Line and Peel AngleF2824 10311.2 Determine the peel line of the sample container to betested and secure the container in the test equipment fixturewith the starting peel point and peel line oriented so that thedirection of the peel travels along the pe
31、el line.11.3 Secure the lid peeling tab in the grip of the forcemeasuring device.11.4 Set the rate of peel to 12 6 0.5 in./min (300 6 12.7mm/min) and start the test.11.5 Upon completion of the test cycle record the measuredresults, remove the sample, and repeat the process for addi-tional samples.12
32、. Report12.1 Report the following information:12.2 Statement of the angle of peel that was used and anyindication of any deviation from the test method as written.12.3 Identification of the source, size, and shape of thesample tested along with any other necessary information touniquely identify the
33、 sample.12.4 Description of any anomalous behavior during thetesting (such as tearing of the lid (cover/membrane).12.5 Measured values for: average seal strength, work, andmaximum seal strength.12.6 Sample conditioning if different than the test method.13. Precision and Bias13.1 The precision of thi
34、s test method is based on aninterlaboratory study (ILS) of ASTM WK18963 conducted in2008. Four laboratories analyzed two different specimen types,reporting data for five peel strength parameters. Every “testresult” represents an individual determination. The laboratorieswere instructed to report twe
35、nty replicate results for eachparameter in order to estimate the repeatability and reproduc-ibility limits of the standard. Except for the use of only fourlaboratories, Practice E691 was followed for the design andanalysis of the data; the details are given in ASTM ResearchReport No. F021028.413.1.1
36、 Repeatability Limit (r)Two test results obtainedwithin one laboratory shall be judged not equivalent if theydiffer by more than the “r” value for that material; “r”istheinterval representing the critical difference between two testresults for the same material, obtained by the same operatorusing th
37、e same equipment on the same day in the samelaboratory.13.1.1.1 Repeatability limits are listed in Table 1 and Table2 below.13.1.2 Reproducibility Limit (R)Two test results shall bejudged not equivalent if they differ by more than the “R” valuefor that material; “R” is the interval representing the
38、criticaldifference between two test results for the same material,obtained by different operators using different equipment indifferent laboratories.13.1.2.1 Reproducibility limits are listed in Table 1 andTable 2 below.13.1.3 The above terms (repeatability limit and reproduc-ibility limit) are used
39、 as specified in Practice E177.13.1.4 Any judgment in accordance with statements 13.1.1and 13.1.2 would normally have an approximate 95 % prob-ability of being correct, however the precision statistics ob-tained in this ILS must not be treated as exact mathematicalquantities which are applicable to
40、all circumstances and uses.The limited number of materials tested and laboratories report-ing results guarantees that there will be times when differencesgreater than predicted by the ILS results will arise, sometimeswith considerably greater or smaller frequency than the 95 %probability limit would
41、 imply. The repeatability limit and thereproducibility limit should be considered as general guides,and the associated probability of 95 % as only a roughindicator of what can be expected.13.2 BiasAt the time of the study, the test specimenschosen for analysis were not accepted reference materialssu
42、itable for determining the bias for this test method, thereforeno statement on bias is being made.13.3 The precision statement was determined through sta-tistical examination of 760 data points, from four laboratories,on a total of two unique material sets. These two differentmaterial types were des
43、cribed as the following:Material A: Gelatin cupsCup: Thermoformed polypropyleneLid: Foil lamination with peel layerMaterial B: Stuffing mix cupsCup: Thermoformed multilayer plastic laminateLid: Plastic film with peel layer13.4 To judge the equivalency of two test results, it isrecommended to choose
44、the material closest in characteristicsto the test material.13.5 The standard deviations of the laboratory averages(above) imply less variability is achieved when multipleresults, in this case 20, are averaged from any given instrumentor laboratory, than when individual replicates are produced andre
45、ported under repeatability conditions.4Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:F02-1028.TABLE 1 Gelatin CupsMaterial AverageAStandard Deviationof Laboratory AveragesRepeatabilityStandard DeviationReproducibilityStandard D
46、eviationRepeatabilityLimitReproducibilityLimitx s x srsRrRFirst Peak, lbf (N) 3.186 (14.172) 0.207 (0.921) 0.297 (1.321) 0.356 (1.584) 0.833 (3.705) 0.997 (4.435)Second Peak, lbf (N) 4.408 (19.608) 0.148 (0.658) 0.396 (1.761) 0.414 (1.842) 1.110 (4.938) 1.158 (5.151)Average Seal Strength, lbf (N) 1.
47、525 (6.784) 0.142 (0.632) 0.076 (0.338) 0.161 (0.716) 0.213 (0.947) 0.450 (2.002)Maximum Seal Strength, lbf (N) 4.391 (19.532) 0.146 (0.649) 0.417 (1.855) 0.432 (1.922) 1.169 (5.200) 1.210 (5.382)Work, in.-lbf (N-m) 8.353 (0.9438) 0.527 (0.0595) 0.410 (0.0463) 0.661 (0.0747) 1.149 (0.1298) 1.852 (0.
48、2092)AThe average of the laboratories calculated averages.F2824 10414. Keywords14.1 average seal strength; cups round containers; flexible;grip separation rate; lid; packaging; peak seal strength; peel;peel angle; seal; seal area; seal strengthAPPENDIX(Nonmandatory Information)X1. IMPORTANT CONSIDER
49、ATIONSX1.1 There are several machines in the marketplace whichprovide for a 45 peel angle when peeling lids (covers) off rigidcontainers. It is important to be sure that the peel angle remainsconstant for the entire peel and that the linear speed parallel tothe plane of the lid is controlled to a constant 12 in./min orwhatever the desired speed is. This is accomplished in theinstrument shown below. In addition, the force gage pulls alongthe axis of the 45 peel so that the force value shown on thegage is exactly the true force. Any other arrangements co
