Alert: Export Control Check Required
Thank you for requesting a TWI Industrial Members Report.
To meet UK government requirements, your request will undergo an Export Control Check. This process reviews the technical content of the report, identifies the end user, and addresses any concerns.
Please submit your request to CRP@twi.co.uk including your name, member company that you work for and your location. We will contact you regarding the request within 2 working days and any additional information required to complete the necessary checks.
We look forward to receiving your request and processing it through our export control procedure.
Thank you,
TWI CRP Operations Team
This content is only available to Industrial Members, Find out how to become a Member of TWI.
TWI Industrial Member Report Summary 657/1998
A M Barnes
Background
The modified 9%Cr1%Mo steel (ASTM A387 grade 91) offers good elevated temperature properties, oxidation resistance and resistance to hot hydrogen attack. It is finding increasing application within the power industry, both for the construction of new plant and the upgrade of existing plant, in, for example, heat exchange tubing and headers. Other industrial sectors, although acknowledging the favourable properties offered by this grade, have yet widely to adopt its use.
It is essential with such steels that good weldment creep properties can be achieved, but adequate toughness is also required to avoid problems during pressure testing and start-up/shut-down. It is acknowledged that current commercial consumable formulations may not be optimised in relation to toughness.