Strain calculations, pitting resistance, and chloride stress corrosion cracking testing are currently used as the key indicators to delimit the minimum bend radius for 22% chrome duplex stainless steels without heat treatment to be 3.3 times the tube diameter for u-bend heat exchanger tubing. However, existing data does not address the limitations of this alloy, in the as cold worked condition, for sour services in the refining industry. This study evaluates the sulfide stress corrosion cracking resistance of as-bent and integrally finned 22% Cr duplex stainless steel UNS-S32205 tubing for refinery sour services by presenting hardness data and corrosion testing per ASTM G48 and NACE TM0177 of tight u-bend specimens with bend radius up to 1.5 times the tube diameter as well as integrally finned tubes. As a follow up from a previous study, the corrosion resistance of as finned 25% Cr super duplex stainless steel will also be presented.

Subject
Test methods, Materials, Tubes, Hardness measurements, Cracking resistance, Maximum hardness, U bends, Pitting, Corrosion resistance, Sulfide stress cracking, Hardness, Stress corrosion cracking, Test specimen
Keywords:
UNS-S32205, UNS-S32750, U-bending, integral finning, duplex stainless steels, pitting, sulfide stress corrosion cracking, SCC
© 2022 Association for Materials Protection and Performance (AMPP). All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise) without the prior written permission of AMPP. Positions and opinions advanced in this work are those of the author(s) and not necessarily those of AMPP. Responsibility for the content of the work lies solely with the author(s).
2022
Association for Materials Protection and Performance (AMPP)
You do not currently have access to this content.