考虑垫片时滞效应的管板-法兰-垫片-螺栓连接系统三维有限元分析--预紧工况和加压工况下密封垫片的压紧应力分析

本文从整体性观点出发,考虑垫片的非线性性质和应力-应变时滞效应,用大型有限元软件ANSYS建立了U形管换热器中等效管板和法兰垫片螺栓连接系统的三维有限元模型,并作为研究报告的第一部分,着重分析了预紧和加压两种工况下垫片材料的非线性与时滞效应、不同的管壳程压差以及不同的螺栓预紧力和不同的螺栓尺寸等因素对法兰接头紧密性(垫片压紧应力的大小和分布状况)的影响;在下一部分中将讨论上述各种因素对法兰接头强度的影响。

3-D Finite Element Analysis for Tubesheet - Gasket - Flange - Bolt System Considering Hysteresis Effect of Gasket Material--Distribution of Compressive Stress on Gasket under Bolt Preloading and Pressured Load Cases

In this paper, a three dimensional finite element analysis model that integrated equivalent tubesheet, bolts and two gaskets, flanges in an U-tube heat exchanger was established and analyzed using ANSYS FEM software considering nonlinear properties and hysteresis effect of the gasket material. In this paper, as Part One of this research, the influences of gasket properties, pressure differentials between tube side and shell side, bolt pre-loading for gasket sealing as well as bolt size (diameter) on tightness (distribution of compressive stress on gasket) of the model were investigated under gasket seating and operating conditions, respectively. The influences of the above factors on strength of the model will be reported in the next paper.