先胀后焊连接中焊接对胀接连接强度的影响 .pdfVIP

先胀后焊连接中焊接对胀接连接强度的影

响

先胀后焊连接中焊接对胀接连接强度的影响

王海峰,马凤丽,桑芝富

(1.南京工业大学机械与动力工程学院,江苏南京210009;2.解放军理工大学理学院,

江苏南

京211101)

摘要:以常见的低碳钢换热管与低合金钢管板胀焊连接接头为研究对象,采用有限

元法进行了换

热器管子与管板焊接过程的模拟,研究了焊接温度场作用下,不胀区长度L对先胀

后焊接头胀接

区残余接触压力的影响.计算结果表明焊接对胀接区的影响主要表现为胀接区接

触范围及接触压

力数值的减小,采用接头接触压力减小系数,和接触面积减小系数,来定量描述焊

接对先胀后焊

接头胀接区的影响,给出了焊接对先胀后焊接头中胀接区影响的定量数值.同时,

研究结果表明,

当增加不胀区长度时,焊接对胀接区的影响有所减小.先胀后焊连接接头设计应考

虑焊接对胀

接的削弱作用,对于中等厚度的管板,胀接连接性能要求较高的胀焊接头,不推荐

采用先胀后焊.

关键词:换热器;管子与管板连接;液压胀接;胀焊结合

中图分类号:TG142.41文献标识码:A文章编号:1001-4837(2010)12—0013—08

doi:10.3969/j.issn.1001—4837.2010.12.003

EffectofWeldingonExpandingStrengthof

Tube——to——tubesheetJointsMadebyWeldingafterExpanding

WANGHai—feng,MAFeng—ii,SANGZhi—fu

(1.MechanicalandPowerEngineeringCollegeofNanjingUniversityofTechnology,Nanjin

g210009,

China:2.InstituteofScience,PLAUniversityofScienceandTechnology,Nanjing211101,C

hina)

Abstract:Incorporatingwidelyusedmaterials,lowcarbonsteelforthetubeandlowalloysteel

forthe

tubesheet,theweldingbetweenthetubeandtubesheetissimulatedusingfiniteelementmetho

d,andthe

effectoftheunexpandedzonelengthLontheexpandedzoneofthejointsmadebyweldingafter

expan.

dingisinvestigated.Theresultsindicatethattheeffectoftheweldingontheexpandedzoneoft

hejoint

exhibitsthereductionofcontactareaandcontactpressure.Thepercentagereductionsofconta

ctpressure

fDrandcontactareafrareintroducedbytheauthortoquantitativelydescribetheeffectofthew

eldingon

theexpandedzoneofthejoint,andthevaluesfortheresearchmodelsarethengiven.Meanwhil

e,there—

suitsalsoindicatethattheeffectisreducedalittlewhentheunexpandedzonelengthLincreases

.The

weakeninginfluenceoftheweldingontheexpandingjointsshouldbetakenintoaccountandth

eexpand—

ed—weldedtube—to—

tubesheetjointswithmoderatetubesheetthicknessarenotrecommendedwhen

highexpandingperformanceisrequired.

Keywords:heatexchanger;tube—to—tubesheetjoint;hydraulicexpanding;expand