【英文标准名称】:DrysealPipeThreads(Inch)
【原文标准名称】:干封管螺纹(英制)
【标准号】:ANSI/ASMEB1.20.3-1976
【标准状态】:现行
【国别】:美国
【发布日期】:1976
【实施或试行日期】:
【发布单位】:美国国家标准学会(US-ANSI)
【起草单位】:ANSI
【标准类型】:()
【标准水平】:()
【中文主题词】:名称与符号;尺寸;管螺纹;管;规范;螺纹
【英文主题词】:Designations;Dimensions;Pipethreads;Pipes;Specification;Threads
【摘要】:DrysealpipethreadsarebasedontheUSA(American)pipethread,however,theydifferfromtheUSA(American)pipethreadinthattheyaredesignedtosealpressuretightjointswithoutthenecessityofusingsealingcompounds.Toaccomplishthissomemodificationofthreadformandgreateraccuracyinmanufactureisrequired.Therootsofboththeexternalandinternalthreadsaretruncatedslightlymorethanthecrests,i.e.rootshavewiderflatsthancrests,sothatmetal-to-metalcontactoccursatthecrestsandrootscoincidentwithorpriortoflankcontact,seeFigure1.Thusasthethreadsareassembledbywrenching,therootsofthethreadscrushthesharpercrestsofthematingthreads.Thissealingactionatboththemajorandminordiameterstendstopreventspiralleakageandmakesthejointspressuretightwithoutthenecessityofusingsealingcompounds,providedthatthematingthreadsareinaccordancewithstandardspecificationsandtolerancesandarenotdamagedbygallinginassembly.Thecontrolofcrestandroottruncationissimplifiedbytheuseofproperlydesignedthreadingtools.Also,itisdesirablethatbothexternalandinternalthreadshavefullthreadheightfortheL1length.However,wherenotfunctionallyobjectionable,theuseofacompatiblelubricantorsealantmaybeusedtominimizethepossibilityofgalling.ThisisdesirableinassemblingDrysealpipethreadsinrefrigerationandothersystemstoeffectapressuretightseal.
【中国标准分类号】:J05
【国际标准分类号】:21_040_20
【页数】:
【正文语种】:英语