船舶存储罐的SSC（硫化物应力裂纹）扩展行为估计
Background
背景
Residual stress solutions for a girth weld
环焊的残余应力求解
Stress intensity factor solution techniques
应力强度因子求解技术
Crack growth behavior in residual stress fields
残余应力、缺口应力和结构应力对应力强度的贡献
H4 Weld Stress Corrosion Cracking in Core
Shroud
芯座的H4（？）焊缝应力腐蚀裂纹
Negligible external loading
很小的外部载荷
Circumferential crack growth up to about 1m long－not surface breaking
容器底部
双坡口6道对接焊
Nozzle to Vessel Weld
接管焊接
Validation by Experiments and Parametric Analyses – Stainless Steel Pipe Girth Weld
试验验证和参数分析—不锈钢钢管环焊
Bending Type 弯曲类型
厚度上自平衡残余应力分量
Significant nonproportional Loading
明显的非比例加载
Stress-Strain Behavior in Residual Stress Field
Upon External Loading – Validity of K
基于外部载荷下的残余应力场中应力-应变行为—K的有效性
“Bending” Type Residual Stresses in Other
Weld Configurations
其它焊接结构的“弯曲”型残余应力
Double-V 30-Pass Butt-Weld At Vessel End
容器末端双坡口30道对接焊
Double-V 6-Pass Butt-Weld At Vessel Bottom
残余应力分析及结果—H4
Analysis of A Growing Surface Crack
扩展中的表面裂纹分析
K Solution for a Long Surface Crack
长表面裂纹的K求解
SSC Growth Behavior Estimation in a Storage Vessel
残余应力影响区域可由 rt 确定
rt
Residual Stress Profiles in the New API 579-
1/ASME FFS-1
新版API 579-1/ASME FFS-1中对残余应力的概述
Observations
小结:
A residual stress typing method is proposed to provide a framework for developing a comprehensive residual stress prescriptions for FFS purpose
3D Finite Element Alternating Method for K Calculations
K计算的3D有限元交替法
• Unique Features:
独特性： • Direct use of a 3D CAD Model
三维 CAD模型的直接使用
• Rapid solution method
Contributions of residual stresses to fracture
残余应力对断裂的贡献
J-Integral: Path Dependency of J in
Conventional Form
J积分：传统形式中J的路径相关性
Through-wall selfequilibrating residual stress component
快速求解方法
• Partial and fully imbedded cracks
部分或完全的嵌入裂纹
• Multiple cracks solved simultaneously
多裂纹同时求解
• Propagating cracks
裂纹扩展
Equilibrium Based Residual Stress
Unit length bending moment:
单位长度的弯矩：
Parametric Descriptions of Through-Wall Axial
Residual Stress Distributions
整个厚度上轴向残余应力分布的参数描述
Residual Stress Influence Region Can be Scaled by
Residual Stress Decomposition: >60 Pass
Temper-Bead Repair Weld
残余应力分解：>60道回火修复焊缝
K Solutions
K求解
Stress Intensity Contributions from Residual
Stress, Notch Stress, and Structural Stress
Validation by Experiments and Parametric Analyses
– Carbon Steel Pipe Girth Weld (Mochizuki ,00)
试验验证和参数分析—碳钢钢管环焊(Mochizuki ,00)
Validations of Self-Equilibrating Type
自平衡类型的验证
Pipe Radial Restraints: A Key Controlling Parameter for
Bending Content in Residual Stress Distribution
管的径向约束：残余应力分布中弯曲中心(???)的关键控制参
数 Hoop strain 环向应变：
Decomposition Technique
基于平衡条件的残余应力分解技术
Actual Residual Stress State
实际残余应力状态
Residual Stress Decomposition
残余应力的分解
Approximate K Solution – Displacement
Controlled
深入理解FFS评估：
• Residual stress estimate for typical welds
显微结构模型预测： 马氏体的成分较高， 但是集中在1mm范围内
Analysis performed at Battelle
Measurements:
Surface: MBEL
Thickness: Bristol University
在Battelle做分析测量： 表面：MBEL（英国三井 巴布科克公司） 厚度：布里斯托尔大学
Residual Stress Decomposition for a Stainless
Steel Joint
不锈钢接头的残余应力分解
C-Mn Vessel Shell Repair with Temper Bead
Techniques
用焊道回火技术修复C-Mn容器壁
Microstructure Model Predictions: Relatively high volumetric fractions For martensite, but very localized within 1 mm range
Hoop stress
环向应力：
Hoop line force
环向力：
F ti S yti
Radial line force
径向力：
Radial modulus
径向模量：
Fr F / r ti / r S yti / rLeabharlann kEt r2
Characteristics length
在残余应力场中裂纹的扩展
Summary
概要
Background
背景
Cracks detected at various welds in high level waste storage tanks
在高级废料存储罐不同焊缝上发现裂纹
External loading: small
外部载荷：小
近似K求解——位移控制
Effects of Through-Wall Residual Stress
Distribution on K
厚度上残余应力分布情况对K值的影响
Validation - a Stainless Steel Core Shroud H4 】
Weld
验证—不锈钢芯座 H4 焊接
板厚对焊趾处厚度方向残余应力分布的影响(r/t=10)
Axial Residual Stress
轴向残余应力
Hoop Residual Stress
环向残余应力
Axial Residual Stress – Through Thickness Bending Component
轴向残余应力—厚度方向上的弯曲分量
特征长度：
4 k 1.285 4EI rt
Displacement wave length
位移波长：
a 2 4.9