Community Research and Development Information Service - CORDIS

Abstract

Final report on Contract No 7210-KB/441, 339, 904, 1 July 1996 to 31 December 1999.

This work is aimed at determining the effect of the most important environmental parameters, such as temperature, pH, chloride and H2S concentrations, of the test solution on the localised corrosion, sulphide stress cracking and stress corrosion cracking of different candidate stainless alloys: martensitic, duplex and austenitic stainless steels. Also the effect of welding has been considered. Three classes of environment, typical of the oil and gas industry, were examined: sour, slightly sour and heavy brines.

The constant load tests confirmed a much better behaviour of duplex grades, compared with martensitic or supermartensitic grades.

The results of slow strain rate tests, which are much more severe tests than constant load or constant strain tests, showed that the fields of application of high nickel containing superaustenitic grades should be still wider than those of duplex stainless steels. Nevertheless, due to the excessive aggressiveness of SSR tests, for most applications, constant load tests can be considered as a reliable method for materials selection.

The results showed that in normal conditions of cathodic protection for offshore applications, the studied materials could be used without any significant risk of hydrogen embrittlement.

The aggressiveness of the brines is related to the concentration and, mainly, to pH. General corrosion is very low for duplex, 316 and supermartensitic steels. Localised corrosion is extremely important in heavy brine application: only the most alloyed steels at temperatures below 200 °C can be considered as immune.

Additional information

Authors: BARTERI M, CSM, Rome (IT);SCOPPIO L, CSM, Rome (IT);VERNEAU M, CLI, Le Creusot (FR);SAARINEN K, VTT (FI)
Bibliographic Reference: EUR 20091 EN (2002), pp.97. Euro: 14.50
Availability: EUR-OP reference: KI-NA-20091-EN-S Available from EUR-OP sales agents. URL: http://eur-op.eu
ISBN: ISBN: 92-894-3149-0
Record Number: 200214864 / Last updated on: 2002-06-26
Category: PUBLICATION
Original language: en
Available languages: en