RELIABILITY OF DISSIMILAR METAL WELDS SUBJECTED TO SULFIDE STRESS CRACKING

RELIABILITY OF DISSIMILAR METAL WELDS SUBJECTED TO SULFIDE STRESS CRACKING. The 6th Saudi Engineering Conference, KFUPM, Dhahran, December 2002.

[img]
Preview
PDF
P297.pdf

Download (1MB) | Preview

Abstract

Serious concerns have been raised in recent years in the Oil & Gas Industry about the reliability of Dissimilar Metal Welds (DMWs) in sour service. The primary reason for these concerns is because DMW joints exhibit small-localized hard zones that are susceptible to Sulfide Stress Cracking (SSC). In the open literature some methods such as preheating have been suggested to overcome the problem of hard zone formation. The objective of this study is to assess the effect of Sulfide Stress Cracking (SSC) on the reliability (mechanical integrity) of DMWs specimens fabricated with different preheat temperatures and electrodes exposed to sour service environment. The National Association of Corrosion Engineers (NACE) Standard Tensile Test TM 01-77-96 Method A was used to determine the influence of SSC on DMWs in a systematic manner. Test results show considerable improvement in the Time-To- Failure as a result of the preheating methods used. However, it does not appear that the hard zones can be reliably eliminated for manual welding methods, even with the nickel-base electrode, and the optimum preheat temperature. Metallographic Examination and Scanning Electron Microscope Characterization were also used to assess the susceptibility and the failure modes.

Item Type: Article
Subjects: Mechanical
Department: College of Engineering and Physics > Mechanical Engineering
Depositing User: Users 4447 not found.
Date Deposited: 04 Jun 2008 06:54
Last Modified: 01 Nov 2019 13:27
URI: http://eprints.kfupm.edu.sa/id/eprint/1702