ABSTRACT

Over the past decade, an increasing number of intergranular stress corrosion cracking (IGSCC) incidents have been observed on carbon steel assets operating in Alberta, Canada. At the time of publication, over 128 distinct cracks have been identified on 26 assets spanning at least 5 operators. All incidents have occurred on uncoated carbon steel operating between 70 °C and 190 °C and exposed to wet mineral wool insulation. Both piping and pressure vessels have been affected. Cracking has been isolated to assets with mineral wool insulation produced after 2003; however, a specific change to mineral wool composition in this timeframe has not been identified. The purpose of this paper is to provide a summary of incidents and investigations that have been reported to date and to update the environmental conditions (window of susceptibility) where insulation driven intergranular stress corrosion cracking has been observed. By drawing attention to this issue, it is the authors’ objective to increase awareness and determine if similar cracking incidents are occurring in other geographical regions.

INTRODUCTION

A growing number of intergranular stress corrosion cracking (IGSCC) incidents have been observed on above ground, thermally insulated, carbon steel assets operating in Alberta, Canada. Stress corrosion cracking (SCC) can occur when a susceptible material is exposed to the right environment and tensile stress. For carbon steel, there are several environments known to cause SCC and a summary is provided in Table 1.1 There is some overlap between known SCC mechanisms and IGSCC that has recently been observed under insulation; however, there are also aspects with IGSCC observed under insulation that appear to be unique. This has prompted additional investigations2-7 and the release of bulletin 2021-36 by the Alberta Energy Regulator to inform industry.8

Several operating companies affected by insulation driven IGSCC are participating in a joint industry project (JIP) to further investigate this cracking mechanism. Through this JIP, a database of cracking events has been compiled to assess the environmental window of susceptibility and identify common traits. Laboratory testing has also been performed to further investigate the cracking mechanism and develop a suitable test method to evaluate the susceptibility of insulation material.

Keywords:
geologist, h2s management, sagd, corrosion inhibition, mineral wool, mineral, enhanced recovery, igscc, geology, production chemistry
Subjects:
Production Chemistry, Metallurgy and Biology, Pipelines, Flowlines and Risers, Improved and Enhanced Recovery, Thermal methods, Corrosion inhibition and management (including H2S and CO2)
This content is only available via PDF.
2024. This work is protected by both domestic and international copyright laws. 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 prior written permission. 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).
You can access this article if you purchase or spend a download.