Modern oil and gas producing installations require alloys of increasing corrosion resistance and strength. This increasing demand on the properties of alloys in such applications result from severe corrosive conditions encountered in the deeper wells that involve high chlorides, high concentrations of hydrogen sulfide, higher pressures and temperatures. Enhanced recovery methods such as steam and carbon dioxide injection and the corrosive chemical environments present challenges of their own. High strength nickel base corrosion resistant alloys (CRA's) that can be used in these sour gas environments are alloy 718, UNS N07718 and alloy 925, UNS N09925. These alloys are age hardenable and provide the required combination of strength and corrosion resistance. The main uses for these alloys are bars, rods and tubes for downhole applications, valves, hangers, tool joints and packers. In this paper, results of slow strain rate test (SSRT) and C-ring stress corrosion cracking (SCC) on alloy 925 and alloy 718 in different sour gas media as proposed by various users (oil and gas industry, suppliers of tooling and components to this industry) are presented.

Subject
Test methods, Materials, Corrosion resistant alloys, Nickel based alloys, Autoclaves, Sour environments, C ring stress corrosion testing, Heat, Corrosion resistance, Titanium alloys, Alloys, Yield strength, Stress corrosion cracking
Keywords:
Slow strain rate test, stress corrosion cracking, C-Ring test, UNS N09925, UNS N07718, alloy 925, alloy 718, corrosion resistant alloy, sour gas, laboratory testing
© 2005 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).
2005
Association for Materials Protection and Performance (AMPP)
You do not currently have access to this content.