Process Optimization of 12Cr1MoVG Big Diameter High Pressure Boiler Pipe to Fit for a New Standard

The heat treatment process data for 12Cr1MoVG big diameter high pressure boiler pipe being manufactured according to GB 5310-2008 are introduced in the paper.An orthogonal heat treatment test is carried out on a full-size sample of a big diameter high pressure boiler pipe to analyze factors affecting the hardness of 12Cr1MoVG big diameter high pressure boiler pipe.The analysis shows the following conclusions.Since surface hardness is defined in GB/T 5310-2017 as an acceptance criteria,more difficulties are put on the heat treatment process.The factors affecting surface hardness are listed in order of importance as tempering temperature,tempering holding time,quenching cooling method and repair depth.It is recommended to,according to real production conditions,do statistical analysis on production data,find the pattern and keep optimizing the heat treatment parameters.