1、Designation: F3270/F3270M 17Standard Practice forCompression versus Load Properties of Gasket Materials1This standard is issued under the fixed designation F3270/F3270M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of l
2、ast revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice measures the compression properties of agasket material by measuring gasket deflection while it issubject
3、ed to an increasing compressive load until a target loadis reached. The load and change in thickness are recorded at adefined loading rate as a function of time for the duration of thetest.1.2 Suggested loading rates are 0.5 MPa/s 72.52 psi/s forall types of gaskets except for expanded polytetrafluo
4、roethyl-ene (PTFE), elastomer, and cork/elastomer gaskets when 0.1MPa/s 14.5 psi/s is used.1.3 The Part A test is performed that measures the compres-sion properties of a gasket material by measuring gasketthickness while it is subjected to an increasing compressiveload until a target load is reache
5、d. This test is performed atroom temperature but may be performed at an elevatedtemperature if desired or when agreed upon by producer anduser.1.4 The Part B test may be performed that measures thecompression properties of a gasket material by measuringgasket thickness while it is subjected to incre
6、asing compressiveloads that includes a sequence or sequences in which the gasketis unloaded followed by a resumption of the compressive loaduntil a target load is reached. The unloading rate is the same asthe loading rate unless different loading and unloading rates aredesired or when agreed upon by
7、 producer and user. This test isperformed at room temperature but may be performed at anelevated temperature if desired or when agreed upon byproducer and user.1.5 The testing parameters for both Parts A and B includingthe gasket material type, gasket dimensions, platen type (RF orFF), target load,
8、loading time, recording interval used duringthe test, loading and unloading rates, and temperature are to bereported with the results.1.6 UnitsThe values stated in either SI units or inch-pound units are to be regarded separately as standard. Thevalues stated in each system may not be exact equivale
9、nts;therefore, each system shall be used independently of the other.Combining values from the two systems may result in non-conformance with the 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 t
10、his standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the De
11、cision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D2000 Classification System for Rubber Products in Auto-motive ApplicationsF104
12、 Classification System for Nonmetallic Gasket Materi-alsF868 Classification for Laminated Composite Gasket Mate-rials3. Terminology3.1 Definitions:3.1.1 final specimen thickness, T2,nspecimen thicknessrecorded at the target stress for the material type.3.1.2 initial specimen thickness, T1,ninitial s
13、pecimenthickness recorded on testing device.3.1.3 original specimen thickness, T0,naverage of speci-men thickness measured in three places 120 apart beforeplacing specimen on the testing device.3.2 Symbols:3.2.1 Ts0original calibration ring thickness.3.2.2 Ts1calibration ring thickness recorded on t
14、estingdevice after bringing platens together.1This practice is under the jurisdiction of ASTM Committee F03 on Gaskets andis the direct responsibility of Subcommittee F03.20 on Mechanical Test Methods.Current edition approved Sept. 1, 2017. Published October 2017. DOI: 10.1520/F3270_F3270M-17.2For r
15、eferenced ASTM standards, visit the ASTM website, 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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, W
16、est Conshohocken, PA 19428-2959. United StatesThis 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
17、Trade Organization Technical Barriers to Trade (TBT) Committee.13.2.3 Ts2final calibration ring thickness recorded at testmaximum load.4. Summary of Practice4.1 Compression CurveThe relationship of the thicknessof a gasket material at a given surface pressure is an importantproperty for both the eva
18、luation of a gasket material or thedevelopment of new materials. Specimens cut from gasketmaterials are subjected at room temperature or an elevatedtemperature or both to an increasing load at a defined loadingrate (see 1.2) perpendicular to the flat surface of the specimenuntil a specified load is
19、attained. Material thickness and loadshould be recorded as a function of time for the duration of thetest to evaluate the load versus thickness relationship for thematerial. When an elevated temperature test is performed it canbe done at the specified load before the specified temperatureis applied,
20、 or with the material at the specified temperaturebefore the load is applied, as agreed upon by the user orproducer or both. The specified temperature should be deter-mined by the material being tested or as agreed upon by theuser or producer or both. Reporting for an elevated temperaturetest should
21、 include the load at which the specified temperatureis applied.4.2 Part A Loading SequenceSpecimens cut from gasketmaterial are subjected at room temperature to an increasingload perpendicular to the flat surface of the specimen until aspecified load is attained. Material thickness and load shouldbe
22、 recorded as a function of time for the duration of the test toevaluate the load versus thickness relationship for the material.4.3 Part B Loading/Unloading SequenceIn addition to aloading sequence, the test may include an unloading sequenceor sequences to measure the thickness as load is decreased.
23、 Ifunloading is included, the gasket thickness is measured bothwhile it is subjected to increasing compressive loads andduring a sequence or sequences in which the gasket is unloadedfollowed by a resumption of the compressive load until a targetload is reached.4.4 The testing parameters, including t
24、he gasket materialtype, gasket dimensions, platen type (RF or FF), the targetload, loading and unloading rates, and temperature, are to bereported with the results.5. Significance and Use5.1 The load versus thickness properties of a gasket materialare an important factor with regard to the selection
25、 of a givenmaterial for use in a particular sealing application.Additionally, compression/load behavior data are a commonrequest from users. The test allows comparison of materials atroom temperature or elevated temperatures or both.Additionally, properties can be evaluated while loading andunloadin
26、g the material at room temperature or elevated tem-peratures or both. The significance of the test method is based,in part, on the assumption that, if a material exhibits too muchcompression at either room temperatures or elevatedtemperatures, it will no longer function as effectively as a seal.The
27、results may be used in certain flange design methods tocharacterize properties for design such as finite element analy-sis (FEA). The results may be used to confirm adequateassembly loading based on measured gasket compression in thefield. Two or more materials can be compared to determinedifference
28、s in their compression properties. A sample ofmaterial can be compared to an established standard orpreviously determined characteristics on original lots of thesame material for quality assurance purposes.5.2 If desired, samples may be tested with a raised profileflange, insert, or calibration ring
29、 described in 6.3 and Fig. 1 sothat the area (2042 mm23.18 in.2) remains constant duringthe test.6. Apparatus6.1 Testing Machine, for applying a known value of com-pressive stresses to specimens. The machine should be capableof applying a stress of up to the expected maximum loads formaterials being
30、 tested to a specimen size described in 7.1 atroom temperature, depending on the indent resistance of thesteel platens and the means of reading the applied load.6.2 Hardened Steel Platens, Two (Rockwell of C35 to 40 orEquivalent), circular shape, larger than the specimen diameter.The faces of the pl
31、atens shall be plane parallel with a surfacefinish between 3.2 and 6.4 m 125 and 250 in., serrated ormachined. Fig. 1 shows a suitable arrangement of steel platensand test specimen. Other finishes as desired or agreed uponbetween the producer and the user may also be used.6.3 Hardened Steel Platens,
32、 Two (Rockwell of C35 to 40 orEquivalent), circular shape, larger than the specimen diameter.If the platens will only be used with a raised face flange, insert,or calibration ring, the faces of the platens shall be planeparallel with a smooth finish. Otherwise, the faces of theplatens shall be plane
33、 parallel with a surface finish between 3.2and 6.4 m 125 and 250 in., serrated or machined. Fig. 1shows a suitable arrangement of steel platens and test speci-men. Other finishes as desired or agreed upon between theproducer and the user may also be used.6.4 Device for Applying Heat to Platens, suff
34、icient toachieve a desired temperature at interface with gasket materialspecimens. In some cases, the loading device itself may beheated, such as with a hot press. Any appropriate means isacceptable. The device shall be capable of increasing thetemperature at a rate between 2 and 5C 3 and 9F perminu
35、te. The temperature difference between the two platensshall not exceed 5C 9F at any time. The maximumtemperature limit can be determined by the user and theirrequirements for their equipment. Other heating rates may beused as desired or agreed upon between the producer and theuser.6.5 Temperature Me
36、asuring Device, for use at interface,such as a thermocouple assembly and a means for recording thevoltage.6.6 Dial or Thickness Measuring Device, an indicating dial,or dials, graduated in 0.025 mm 0.001 in. or a digital deviceto show or record the thickness of the specimen during the test.6.7 Shield
37、A safety shield for protection from severeoutgassing that may occur during the test.F3270/F3270M 1726.8 Gauge, for making specimen thickness measurements inaccordance with Classification F104.6.9 Metal Foil (for example, Inconel, Nickel, and StainlessSteel), capable of low creep at the desired maxim
38、um testtemperature may be used between the test gasket and theplatens to protect the platen surfaces and prevent the samplefrom sticking to the platens. Recommended thickness is 0.05mm 0.002 in. If a metal foil is used, it shall be reported in thefinal results.7. Test Specimens7.1 Sheet-Type Gasketi
39、ng (see Classifications F104, F868,or D2000)The gasket shall be die cut in the shape of anannulus with clean smooth edges. The bore and outsidediameter shall be concentric to 60.5 mm 60.02 in.7.1.1 The recommended annular specimen size is 90 6 0.5mm 3.55 6 0.02 in. outside diameter by 50 6 0.5 mm 1.
40、976 0.02 in. inside diameter. Three specimens should beprepared for each material that is to be evaluated.7.1.2 The recommended test specimen thickness may varydepending on the type of testing machine used, type of materialbeing evaluated, and the application to which the results aredirected. The ex
41、act effect of specimen thickness on the testresults is not being addressed in this practice other than toacknowledge it will most likely influence the results and shouldbe a part of the report as specified in Section 13.7.2 Solid Form-in-Place Gasketing (see ClassificationF104)A 211 mm 8.30 in. long
42、 piece of standard sizematerial between 3.18 and 4.76 mm 0.125 and 0.1875 in.nominal size or width shall be formed into a circle of 65 mm2.56 in. mean diameter. The ends of the Type 4 material shallbe so laid as to have a 6.35 6 1.59 mm 0.25 6 0.0625 in.overlap to complete the specimen. The Type 5 m
43、aterial shallhave an overlap of 1.59 6 0.79 mm 0.0625 6 0.0313 in. tocomplete the specimen. Three specimens should be preparedfor each material that is to be evaluated.7.3 Metallic Gasketing such as Spiral Wound, Jacketed, orKammprofile GasketingStandard American Society of Me-chanical Engineers (AS
44、ME) or European Standards (EN) sizesthat are smaller than the platen diameter may be testedassuming that the desired test load can be achieved.8. Calibration and Standardization8.1 Since accurate thickness measurements depend on theeffects of thermal and mechanical characteristics on the fixture,in
45、addition to the effect produced by the test gasket, it isnecessary that the fixture be calibrated in accordance withSections 11 or 12 using only the raised profile insert orcalibration ring. Increase the platen load to the desired maxi-mum test load at room temperature while recording the loadand ch
46、ange in thickness for the duration of the test as a functionof time to obtain the values Ts0, Ts1, and Ts2(which correspondto T0, T1, and T2in Section 11).8.2 If a test machine performs calibration automatically as apart of its program, the procedures in this section are notnecessary and inclusion o
47、f the values Ts0, Ts1, and Ts2inSection 13 are not required.8.3 It is recommended that the test machine be calibratedapproximately every 100 cycles and, between these periods,the calibration results from the previous test be used in Section13.FIG. 1 Test Assembly for Determining Load versus Compress
48、ionF3270/F3270M 1739. Data9.1 For each test, record the gasket load versus the gasketthickness as a function of time for the duration of the testbeginning at T1until the maximum load, T2is reached.9.2 Record the results for each of the given calculations, T0,T1, and T2for the three specimens tested
49、and determine theaverage values.10. Conditioning10.1 Condition the cut specimens in accordance with theappropriate procedure specified in Classification F104 withrespect to the type of gasket material from which the specimensare cut.11. Procedure for Part ALoading Sequence Only11.1 Original Thickness Measurement, T0Measure thethickness of the conditioned gasket specimen according toClassification F104. The specimen thickness is measured withthe micrometer at three equally spaced places approximately120 apart. The resu
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