超超临界火力发电机组SA-335P92钢焊接质量控制

Welding quality control of SA-335P92 steel for ultra supercritical thermal power generating unit

超超临界机组在我国运用得越来越多,作为超超临界机组主蒸汽、再热蒸汽热段管道、高温过热器集箱以及高温再热器集箱最常用的钢材SA-335P92,由于其首次运用于国内电站锅炉,其焊接质量控制受到了各大电厂及各大电建单位的重视。文中主要从SA-335P92钢焊接前的工艺评定准备、焊工培训、技术准备、坡口加工等方面简单介绍了从SA-335P92钢焊接前的准备工作,同时简单介绍了超超临界机组安装过程中,SA-335P92钢现场焊接的主要方法及主要焊接工艺,列出了SA-335P92钢现场焊接过程中热输入控制、层间温度控制以及层间清理等方面应该注意的问题。文中还简单介绍了SA-335P92钢焊后热处理工艺、热处理时机、现场常用的热处理方式以及热处理过程中应注意的一些问题。此外,文中还根据超超临界机组现场安装的特点,简单介绍了SA-335P92钢焊缝在无损检测、硬度测试、金相分析等方面应注意的一些问题。

The ultra-supercritical unit was used more and more in our country.As the most commonly used steel SA-335 P92 for the main steam,reheat steam heat section pipe,high temperature superheater set box and high temperature reheater box,the welding quality control of the super supercritical unit was first used in the domestic power plant boiler,and its welding quality control had been affected by various big power plants and the major electric construction units.Paid attention to it.This paper introduced that the preparatory work of the SA-335 P92 steel before welding,the welder training,the technical preparation,the groove processing and so on.At the same time,it briefly introduced the main method and the main welding process of the field welding of the SA-335 P92 steel in the installation process of the wtra-supercritical unit,and list the main welding process.Attention should be paid to welding line energy control,interlayer temperature control and storey cleaning during field welding of SA-335 P92 steel.In this paper,the heat treatment process of SA-335 P92 steel after welding,the time of heat treatment,the common heat treatment methods in the field and some problems that should be paid attention to during the heat treatment process were also briefly introduced.In addition,according to the characteristics of the site installation of super supercritical unit,this paper briefly introduced some problems that should be paid attention to in nondestructive testing,hardness test and metallographic analysis of SA-335 P92 steel weld.