核二三级管道疲劳分析方法简介  

Introduction to Fatigue Analysis Methods of Nuclear Grade 2 & 3 Pipelines

作　　者：刘雪林 刘美平 

机构地区：[1]深圳中广核工程设计有限公司,广东深圳518172

出　　处：《压力容器》2018年第2期43-48,共6页Pressure Vessel Technology

摘　　要：在核电站的建造设计过程中,为了防止管道失效,RCC-M规范规定,除了应考虑自重、压力和地震等载荷变化导致的应力变化外,还规定应该考虑热膨胀和热弯曲应力变化对管道疲劳的影响。RCC-M规范B3650篇明确规定核一级管道必须进行详细的疲劳分析,而二三级管道需要按照C3112篇疲劳排除方法来确定是否需要做详细疲劳分析。不能满足疲劳排除原则的核二三级管线进行详细疲劳分析,能够满足疲劳排除原则的管线不需要进行详细的疲劳分析,但需要在管道应力计算时考虑应力范围减弱系数。详细介绍RCC-M规范中疲劳排除以及应力范围减弱系数的计算方法,并以核取样系统为例,具体说明核二三级管道系统在设计过程中如何考虑疲劳效应。结果表明,经受温差和压差较大载荷时,核二三级管道也需要进行详细的疲劳分析;而承受次数较多但温差和压差不大载荷时,重点考虑应力范围减弱系数对管道应力计算的影响。Code RCC -M explicitly stipulates that in addition to the stress change caused by load changes such as self-weight, inner pressure and earthquake, the influence of thermal expansion and thermal ben- ding stress on pipeline fatigue should also be considered to prevent pipe failure. In the chapter B3650,it clearly states that nuclear class 1 pipe must be detailed fatigue analysis. As to class 2 and class 3 pipe,it should be based on the elimination method in chapter C3112, and carrying on precise study if fails the ex- clusion rule, detailed fatigue analysis is unnecessary but should take stress reduction factor into considera- tion while loads meet the principal on the other hand. In this paper, the rule of fatigue elimination and the calculation method of stress reduction coefficient in RCC - M specification are introduced in detail. Taking nuclear sampling pipeline as an example, the paper shows how to consider the fatigue effect in the design process of nuclear class 2 and class 3 pipeline system. The results show that, when subjected to large tem- perature and pressure difference, nuclear class 2 and class 3 pipeline should make detailed fatigue analy- sis, in case of suffering sufficient times but small temperature and pressure difference loads, the stress reduction factor should be a major consideration.

关 键 词：核二三级管道 疲劳排除 应力范围减弱系数 RCC—M规范 

分 类 号：TH49[机械工程—机械制造及自动化] TL35[核科学技术—核技术及应用]