【英文标准名称】:StandardTestMethodforObtainingHydrostaticDesignBasisforThermoplasticPipeMaterialsorPressureDesignBasisforThermoplasticPipeProducts
【原文标准名称】:获得热塑性管道材料静水压设计基数或热塑性管道制品用压力设计基数的试验方法
【标准号】:ASTMD2837-2008
【标准状态】:现行
【国别】:美国
【发布日期】:2008
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:F17.40
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:Circumferentialexpansion;Design--pipingsystems;Hydrostaticdesignbasis(HDB);Polyethylene(PE)pipe;Stress--plastics;Thermoplasticpipe/tube/fittings;Validation
【摘要】:Theprocedureforestimatinglong-termhydrostaticstrengthorpressure-strengthisessentiallyanextrapolationwithrespecttotimeofastress-timeorpressure-timeregressionlinebasedondataobtainedinaccordancewithTestMethodD1598.Stressorpressure-failuretimeplotsareobtainedfortheselectedtemperatureandenvironment:theextrapolationismadeinsuchamannerthatthelong-termhydrostaticstrengthorpressurestrengthisestimatedfortheseconditions.Note38212;Testtemperaturesshouldpreferablybeselectedfromthefollowing:40x00B0;C;50x00B0;C;60x00B0;C;80x00B0;C;100x00B0;C.Itisstronglyrecommendedthatdataalsobegeneratedat23x00B0;Cforcomparativepurposes.Thehydrostaticorpressuredesignbasisisdeterminedbyconsideringthefollowingitemsandevaluatingtheminaccordancewith5.4.Long-termhydrostaticstrengthorhydrostaticpressure-strengthat100000h,Long-termhydrostaticstrengthorhydrostaticpressure-strengthat50years,andStressthatwillgive5%expansionat100000h.Theintentistomakeallowanceforthebasicstress-straincharacteristicsofthematerial,astheyrelatetotime.Resultsobtainedatonetemperaturecannot,withanycertainty,beusedtoestimatevaluesforothertemperatures.Therefore,itisessentialthathydrostaticorpressuredesignbasesbedeterminedforeachspecifickindandtypeofplasticcompoundandeachtemperature.Estimatesoflong-termstrengthsofmaterialscanbemadeforaspecifictemperatureprovidedthatcalculatedvalues,basedonexperimentaldata,areavailablefortemperaturesbothaboveandbelowthetemperatureofinterest.Hydrostaticdesignstressesareobtainedbymultiplyingthehydrostaticdesignbasisvaluesbyaservice(design)factor.Pressureratingsforpipemaybecalculatedfromthehydrostaticdesignstress(HDS)valueforthespecificmaterialusedtomakethepipe,anditsdimensionsusingtheequationsin3.1.11.4.5.1Pressureratingsformultilayerpipemaybecalculatedbymultiplyingthepressuredesignbasis(PDB)bytheappropriatedesignfactor(DF).1.1Thistestmethoddescribestwoessentiallyequivalentprocedures:oneforobtainingalong-termhydrostaticstrengthcategorybasedonstress,referredtohereinasthehydrostaticdesignbasis(HDB);andtheotherforobtainingalong-termhydrostaticstrengthcategorybasedonpressure,referredtohereinasthepressuredesignbasis(PDB).TheHDBisbasedonthematerial''slong-termhydrostaticstrength(LTHS),andthePDBisbasedontheproduct''slong-termhydrostaticpressure-strength(LTHSP).TheHDBisamaterialpropertyandisobtainedbyevaluatingstressrupturedataderivedfromtestingpipemadefromthesubjectmaterial.ThePDBisaproductspecificpropertythatreflectsnotonlythepropertiesofthematerial(s)fromwhichtheproductismade,butalsotheinfluenceonproductstrengthbyproductdesign,geometry,anddimensionsandbythespecificmethodofmanufacture.ThePDBisobtainedbyevaluatingpressurerupturedata.TheLTHSisdeterminedbyanalyzingstressversustime-to-rupture(thatis,stress-rupture)testdatathatcoveratestingperiodofnotlessthan10000handthatarederivedfromsustainedpressuretestingofpipemadefromthesubjectmaterial.Thedataareanalyzedbylinearregressiontoyieldabest-fitlog-stressversuslogtime-to-failstraight-lineequation.Usingthisequation,thematerial''smeanstrengthatthe100000-hintercept(LTHS)isdeterminedbyextrapolation.Theresultant......
【中国标准分类号】:P94
【国际标准分类号】:83_140_30
【页数】:16P.;A4
【正文语种】:英语