Baosteel’s Study on Chemical Composition Control of Grade 91 Steel

The chemical composition changes of T91 and P91 of Grade 91 steel in ASME standards are introduced in the paper.Also discussed is the modification plan（Item 14-1540） proposed by U.S.Electric Power Research Institute（EPRI）in 2014 of chemical composition of Grade 91 steel in ASME standards.Furthermore，the control levels of chemical composition of Grade 91 steel at home and abroad are compared.The results indicate that the Item 14-1540 modification plan is beneficial to the safety and reliability of Grade 91 steel to be used on power plant boilers，and the chemical composition of Grade 91 steel made by Baosteel can meet the control requirements of the latest ASME Code Case 2864—2015.To promote the control requirements of the latest ASME Code Case 2864—2015 is good for the improvement of the quality of T91 and P91 products.