制氢转化炉炉管服役后的安全性分析

SAFETY ANALYSIS OF HYDROGEN REFORMER TUBES AFTER SERVICE

针对已服役近50 000 h的制氢转化炉炉管,分析了炉管的硬度、壁厚、蠕胀与金相组织,并与炉管运行近25 000 h的性能和已有的研究结果进行比较。结果表明炉管的硬度、壁厚、蠕胀等性能参数均在正常范围内。炉管组织的晶粒没有发生明显的长大,碳化物仍呈弥散分布状态。相对于运行25 000 h炉管的组织,仅发生了碳化物长大与部分晶界粗化。除少量超温炉管有蠕变孔洞外,正常运行的炉管的损伤程度为Ⅱ级,对应的服役寿命损耗在总寿命的20%范围内。

This paper makes an analysis on hydrogen reformer tubes which have operated for nearly fifty thousand hours.It analyzes the hardness, wall thickness,creep expansion and metallographic structure of the reformer tubes.It also compares the performance of the tubes after nearly twenty-five thousand hours' operation with the reported research results.And the comparison indicates that performance parameter of the tubes such as their hardness,wall thickness and creep expansion are all within the normal range.Grains of the tubes didn't grow obviously, with dispersed carbide in the tubes.However,diameter of carbide grew larger and part of grain boundary became coarser after the twenty-five- thousand-hour service.Except for the over-temperature tubes with a small amount of creep cavities, the damage state of tubes is in grade Ⅱ.