ASTM_F_2837_-_11.pdf

Designation:F283711Standard Test Method forHot Compression Properties of Gasket Materials1This standard is issued under the fixed designation F2837;the number immediately following the designation indicates the year oforiginal adoption or,in the case 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 covers a means of measuring the hotcompression properties of a gasket material by measuring itscreep under a constant load at both room temperature and whileincreasing the temperature.Short term creep properties includ-ing both cold and hot creep,total creep and compression set ofa gasket material can be determined.1.2 The values stated in SI units are to be regarded asstandard.The values given in parentheses are for informationonly.1.3 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 limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodF104 Classification System for Nonmetallic Gasket Materi-als3.Terminology3.1 Symbols:T0=original specimen thicknessT1=cold thickness under load(specimen thickness after a5-min hold under load at room temperature)T2=hot thickness under load(specimen thickness at maxi-mum test temperature under load)T3=final specimen thickness(after specimen has beenremoved from the machine and cooled)Ts0=original calibration ring thicknessTs1=calibration ring thickness(after a 5-min hold underload at room temperature)Ts2=calibration ring thickness(at maximum test tempera-ture under load)Ts3=final calibration ring thickness(after specimen hasbeen removed from the machine and cooled)4.Summary of Test Method4.1 Specimens cut from gasket material are subjected to astress perpendicular to the flat surface of the specimen for aspecified time at room temperature,and then the temperature isincreased at a defined rate while the stress remains constant.The recommended maximum temperature limit for the test is300C(572F).The desired gasket load for the test is 25.5 MPa(3700 psi).Dimensional changes to the thickness are deter-mined while the gasket is under stress and after the stress hasbeen removed.Tests may be performed on a gasket material atvarious temperatures or stresses as agreed upon between theproducer and the user,to determine the relationship betweentemperatures at a constant stress.5.Significance and Use5.1 The hot compression properties of a gasket material,including creep resistance and compression set,are a majorfactor with regard to the selection of a given material for use ina particular sealing application.The significance of the testmethod is based,in part;on the assumption that if a materialexhibits too much creep at elevated temperature that it will nolonger function as effectively as a seal.This assumption canonly be used as a guide;however,since exact yield or failurepoints are difficult to define for gasket materials(which areusually viscoelastic in nature).Two or more materials can becompared to determine differences in their hot compressionproperties.A sample of material can be compared to anestablished standard or previously determined characteristicson original lots of the same material,for quality assurancepurposes.5.2 Samples are to be tested with a raised profile insert orcalibration ring described in 6.3 and Fig.1 so that the area(2042 mm2(3.17 in.2)remains constant during the test.1This test method is under the jurisdiction of ASTM Committee F03 on Gasketsand is the direct responsibility of Subcommittee F03.40 on Chemical Test Methods.Current edition approved April 1,2011.Published May 2011.Originallyapproved in 2010.Last previous edition approved in 2010 as F2837 10.DOI:10.1520/F2837-11.2For referenced 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,West Conshohocken,PA 19428-2959.United States1 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 51.7 MPa(7500 psi)(tolerance of65%),depending on the indent resistance of the steel platensand 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.A suitable size is a diameter of approximately 152 mm(6 in.).The faces of the platens shall be plane parallel wit