Risk-Based Inspection

Damage rates will often vary as the mechanism progresses. In some cases, the
mechanism is self-limiting (i.e. after progressing to a certain point), and damage
will nearly arrest. In other cases, damage will occur in a slow, stable manner
until it reaches a point where failure occurs. In some cases, damage by one
mechanism may progress to a point at which a different mechanism takes over
to control the rate of further damage (e.g. pitting that gives rise to stress
corrosion cracking). 腐 蚀 率 是 多 变 化 的 , 有 的 时 候 加 速 , 自 限 , 或 从 一 种 损 伤 机 理 改
变 为 另 种 损 伤 机 理 , 比 如 点 蚀 导 致 环 境 应 力 开 裂 等 .
The following parameters should be considered in the determination of damage
rates: 确 定 损 伤 率 的 应 要 考 虑 参 数
a) fluid stream composition, including electrolytes and ions in solution; 流 体 流
组 成 , 包 括 在 溶 液 电 解 质 和 离 子
b) the temperature, humidity and corrosiveness of the atmosphere or soil;
温 度 , 湿 度 和 大 气 中 或 土 壤 的 腐 蚀 性
c) process temperature; 工 艺 温 度
d) the flow velocity; 流 速
e) the amount of dissolved oxygen; 溶 解 氧 气 量
API 580
Charlie Chong/ Fion Zhang