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Welding and Repair of Creep Resisting Steels (TP91)

Project Code: 0903-06


Carry out a literature review including codes and standards requirements for welding, repair and PWHT of T/P91 steels.

Develop best practice guidelines for welding and repair of the high temperature steel alloy T/P91 used in modern power generation construction.

Publish a knowledge summary in Bulletin highlighting the above best practice guidelines.

Project Outline

Confirm and analyse welding procedures consistent with that which can be instigated in the fabrication shop. Including cross-over and dissimilar joints.

Carry out welding with selected procedures and analyse the variability of microstructure, HAZ width and hardness with respect to welding parameters to develop a best practice for evaluation of such properties for site welds.

Investigate the effect of repairs on material properties including: types of repairs allowed (Hot and Cold), number of repairs at same location(s) and extent of repair.

Develop a best practice guide for the fabrication and repair of T/P91 steels, including PWHT.

Relevant Industry Sectors

Power generation, Oil and gas

Technical and Economic Benefits

A better understanding of best practice in welding T/P91 alloys under different conditions will provide confidence in the power generation industry to pursue new build and life extension options.


Industrial Member Report

Access the Industrial Member Report resulting from this programme:

Current Welding Practice and Investigation of Weld Repair Without Post-weld Heat Treatment for Grade 91 Steels


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