Preferential weldment corrosion in low-alloy steel oil and gas production flowlines and other equipment in the presence of C62 and NaCl solutions has been recognised as a persistent problem. Previously, it was thought that adding small quantities of nobler elements such as Ni to the filler metal would prevent selective attack of weldment components by creating a cathodic weld metal and thus ensuring a small difference in rest potential (ΔE) between the weld and parent metals in CO2 environments. Although this approach has proved effective, it has been found that preferential corrosion has occurred in weldments that are virtually identical to others that corrode acceptably in service. It is thought that this is due to the small quantities of Ni increasing die corrosion rate of the low-alloy steel.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:493956 |
| Date | January 2002 |
| Creators | Adams, Rachel |
| Publisher | University of Manchester |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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