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Cross-Weld Creep Properties of Advanced 9% Cr Steels

Project Code: 0902-06


Demonstrate that some of the newer welding technologies yield benefits in terms of increased productivity and improved cross-weld creep performance, compared with existing welding processes for 9%Cr steels.

By means of cross-weld creep testing, to demonstrate that new high Cr steels show little or no diminution of creep strength in the HAZ.

Project Outline

A programme of evaluation of the effects of welding process (the new variant technologies) on existing grade 91 steel and of the new emerging steels will be carried out, and their productivity compared. Butt welds will be deposited in each of the steels, and weld metal mechanical properties, including cross-weld creep rupture testing will be carried out.

The detailed metallurgical investigation will be carried out to gain an understanding of the microstructural changes occurring in the HAZ, and the reasons for the anticipated good HAZ creep rupture strength.

Relevant Industry Sectors

Power, Oil, Gas and Chemicals

Technical and Economic Benefits

Confidence in one or more improved alternatives to grade 91 steels that are currently widely used, but which require constant monitoring and often weldment repair well within the design life.

Carrying out welding, toughness, creep and hot corrosion tests will help demonstrate our facilities to the international community, and may lead to collaborative or single client work.

An increased understanding of the productivity and weld quality implications of using the new welding process, with an anticipated improvement in productivity and weld quality.

Industrial Member Report

Access the Industrial Member Report resulting from this programme:

Review of Type IV Cracking in 9-12%Cr Creep Strength Enhanced Ferritic Steels


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