热预应力自增强厚壁圆筒研究.pdf

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1、第52卷第17期机械工程学报Vol.52No.172016年9月JOURNALOFMECHANICALENGINEERINGSep.2016DOI：10.3901/JME.2016.17.168*热预应力自增强厚壁圆筒研究12朱瑞林朱国林(1.湖南师范大学工程与设计学院长沙410081；2.江西警察学院基础课部南昌330103)摘要：厚壁圆筒自增强处理技术的关键在于预应力。传统的自增强处理技术采用的是机械预应力方法，即在圆筒投入使用前，对其施加超过操作压力的自增强压力，使之获得残余预应力。考虑到厚壁圆筒内、外壁存在温差时，筒壁中有热应力产生，因此针对厚壁圆筒自增强问题，提出了以热应

2、力作为预应力的自增强技术。具体研究了圆筒壁厚、温差等对热应力与总应力(热应力与操作应力的叠加)的影响、热应力与总应力的变化趋势、各种参数间的约束条件；在分析热应力与总应力特性的基础上，得出最佳设计条件，提出了基于第四强度理论的热预应力自增强厚壁圆筒的设计方法。结果表明，热预应力能有效地降低和均化厚壁圆筒的操作应力；按照所提出的设计方法，在确保圆筒安全的前提下，可使圆筒获得最大的承载能力和最小的壁厚。关键词：厚壁圆筒；自增强；预热应力；强度；总应力中图分类号：TH49StudyonAutofrettagedThick-walledCylinderswithThermalPre-str

3、esses12ZHURuilinZHUGuolin(1.CollegeofEngineeringandDesign,HunanNormalUniversity,Changsha410081;2.BasicCoursesDepartment,JiangxiPoliceCollege,Nanchang330103)Abstract：Thekeytoautofrettagetechnologyofthick-walledcylindersliesinpre-stresses.Intraditionalautofrettagetechnology,pre-stressesincylinde

4、rsareproducedbymechanicalactions,thatis,thecylindersaresubjectedtopressureshigherthanoperationpressuresforpre-stressestobeproducedbeforetheyareputintouse.Inconsiderationofthattherearethermalstressesinthewallofacylinderwhenthereistemperaturedifferencebetweentheinsideandoutsidesurfaces,forautofr

5、ettageofthick-walledcylinder,thetechnologyofautofrettagewiththermalpre-stressesisthusproposed.Theeffectsofthicknessandtemperaturedifferenceonthermalstressesandtotalstresses(thermalstressesplusoperationstresses)arestudied.Thevaryingtrendsofthermalstressesandtotalstressesareanalyzed.Thecondition

6、sofconstraintsonavarietyparametersareinvestigated.Onthebasisofanalyzingthecharacteristicsofthermalstressesandthetotalstresses,theoptimumdesignconditionsareobtained,andamethodologyfordesignofautofrettagedthick-walledcylinderswiththermalpre-stressesbasedonthefourthstrengththeoryispresented.Itiss

7、hownthatthethermalpre-stressescaneffectivelyreduceandeventheoperationstressesofathick-walledcylinder,andaccordingtothepresentedmethodologyfordesign,themaximumload-bearingcapacitiesandtheminimumthicknessesofcylinderscanbeobtainedunderthe