不同温度下胶乳复合垫片蠕变松弛特性分析  

Analysis of Creep Relaxation Characteristics of Latex Gasket atDifferent Temperatures

作　　者：郭子玉 李遇贤[1] 刘美红[1] 张静全 张杰[1] GUO Ziyu;LI Yuxian;LIU Meihong;ZHANG Jingquan;ZHANG Jie(Faculty of Mechanical and Electrical Engineering,Kunming University of Science and Technology,Kunming Yunnan 650500,China)

机构地区：[1]昆明理工大学机电工程学院,云南昆明650500

出　　处：《润滑与密封》2024年第3期68-73,共6页Lubrication Engineering

基　　金：国家自然科学基金项目(51765024);昆明理工大学分析测试基金项目(2021M20202103047)。

摘　　要：螺栓法兰接头的垫片在高温下长期使用,会发生蠕变松弛。垫片的蠕变松弛会导致接头内部流体泄漏,因此建立一种预测密封垫片蠕变和应力松弛的方法尤为重要。利用三参量开尔文流体模型建立一种预测垫片高温蠕变残余应力随时间变化的解析模型,并对胶乳复合垫片进行不同温度、不同应力载荷的蠕变松弛实验。研究结果表明:胶乳复合垫片在相同应力载荷下温度越高残余应力整体下降越明显,且应力载荷越大,损失的应力越多,随时间的推移,残余应力下降逐渐平缓;垫片的高温蠕变松弛行为会导致垫片质量和厚度下降,但随着垫片应力载荷的继续增加,垫片质量和厚度下降的趋势会有所减缓,而随温度的增加,质量和厚度持续降低,且下降趋势不会变缓。三参量开尔文流体模型的预测值与实验数据非常接近,最大误差为4.104%,该模型可以准确地描述垫片的力学行为以及垫片由于蠕变松弛引起的应力载荷损失。Creep relaxation occurs when the gaskets of bolted flange joints are used for a long time.Creep relaxation of the gasket can cause fluid leakage inside the joint.To prevent leakage of sealing fluid from flange joints,it is important to establish a method to predict gasket creep and stress relaxation.A three-parameter Kelvin fluid model was used to establish an analytical model for predicting the residual stress of gaskets at high temperature creep with time,and the creep relaxation experiments of the latex composite gasket at different temperatures and different stress loads were carried out.The results indicate that under the same stress load,the higher the temperature of the latex composite gasket,the more obvious the residual stress decreases,the greater the stress load,the more stress is lost,and the residual stress decreases gradually over time.The high temperature creep relaxation behavior of the gasket can lead to the decrease of the mass and thickness of the gasket.But as the gasket stress load continues to increase,the decreased trend of mass and thickness of the gasket at the stress load will be slowed down.However,with the increase of temperature,the mass and thickness of the gasket continue to decrease,and the downward trend will not slow down.The predicted value of the three-parameter Kelvin fluid model is very close to the experimental data,and the maximum error is 4.104%.The model can accurately describe the mechanical behavior of the gasket and the stress load loss caused by the creep relaxation.

关 键 词：密封 垫片 高温蠕变松弛 解析模型 残余应力 

分 类 号：TB42[一般工业技术] TH16[机械工程—机械制造及自动化]