Material Selection Corrosion Prevention Offshore Oil & Gas
Inquiries and interpretations for NACE MR0175/ISO 15156 -
In 2003 the ISO 15156 Maintenance Panel was set up to maintain this widely used standard during and after publication.
Since that time this panel together with NACE TG 299 and ISO TC67 WG7 have processed and accepted more than 20 proposals for amendment. Amendments made to NACE MR0175/ISO 15156 are published as Technical Corrigenda or Technical Circulars the references to which are provided at the end of this document.
These Technical Corrigenda and Technical Circulars were incorporated into the main three parts of ISO 15156, approved by the member countries of ISO/TC 67, and the 2009 version of ISO 15156 was published in October 2009.
During the same period the Maintenance Panel has dealt with more than 120 inquiries for help with interpretation. The majority of these inquiries and the responses provided are reproduced below.
The inquiries and responses are listed in the order of the sections of NACE MR0175/ISO 15156-1, -2, and -3 to which they refer.
These responses represent a consensus of the members of the ISO 15156 Maintenance Panel and should not be construed to reflect the opinions of NACE International, its officers, directors, or members.
AQUEOUS CO2 CORROSION OF MILD STEEL A tutorial from Ohio Uversity on CO2 -
H2S corrosion in Oil&Gas- As the oil and gas emerge from the
geological formation they are always accompanied by some water and varying
amounts of “acid gases”: carbon dioxide, CO2 and hydrogen sulfide, H2S. This
is a corrosive combination which affects the integrity of mild steel. Even if
this has been known for over 100 years, yet aqueous CO2 and H2S corrosion of
mild steel still represents a significant problem for the oil and gas industryAlloys for Offshore
Applications – Duplex and Super Duplex Stainless Steels, Cupronickels and
Corrosion Mechanisms
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Norsok Standard: Material Selection for Corrosion
Control in Offshore Oil&Gas Facilities - This NORSOK standard gives
recommendations, requirements and guidelines for materials use in oil and gas
production. This revision 4 includes requirements from NORSOK M-CR-505
"Corrosion monitoring design", which is withdrawn. The evaluation of internal
corrosivity in hydrocarbon systems is rewritten and considers corrosion
inhibitor availability instead of efficiency, and the maximum hardness and yield
strength requirements of materials to be cathodically protected have been
lowered.
Norsok Software for CO2
Corrosion Prediction in Oil&Gas CO2 corrosion, software for
corrosion prediction - A description of the calculation model, the algorithms and the conditions for the corrosion rate calculations are given.
In additions, methods and algorithms for calculation of essential input parameters to the corrosion rate calculations are given.
Article on CRA Materials Selection in Oil&Gas Facilities
Corrosion is a dominant contributing
factor to failures and leaks in pipelines. To deal with this issue, the CAPP
Pipeline Technical Committee has developed industry recommended practices to
improve and maintain the mechanical integrity of upstream pipelines. They are
intended to assist upstream oil and gas producers in recognizing the conditions
that contribute to pipeline corrosion incidents, and identify effective measures
that can be taken to reduce the likelihood of corrosion incidents. This document
addresses design, maintenance and operating considerations for the mitigation of
internal corrosion in sour gas pipeline systems constructed with carbon steel
materials. Within this document, sour gas corrosion could be expected to occur
when: · H2S concentration in the gas phase is greater than 500 ppm (These limits
are supplied as a guideline only and may not be absolute) · H2S is dissolved in
free water This document does not address failures due to environmental cracking
such as sulphide stress cracking (SSC) and hydrogen induced cracking (HIC). This
document also does not address gas gathering systems fabricated with aluminum
and non-metallic materials.
The NACE MR0175/ISO 15156 International
Standard for the selection of crackresistant materials for use in H2S-containing
environments has had a significant impact on various aspects of the oil & gas
industry in Canada. For this reason, CAPP Pipeline Technical Committee felt it
was important to create a supporting document, which could be used by industry
as a reference tool to: · provide a brief overview of the NACE/ISO publication,
outlining the most significant changes and their implication to the industry, ·
provide guidance and assistance on how to apply the new publication using simple
to follow flowcharts, and clarification examples, · provide sample forms which
could be used to meet the intent of the publication. This document is not
intended to supersede the NACE MRO175/ISO 15156 International Standard. It is
intended to serve a as a Guide for working with and complying with the NACE
MRO175/ISO 15156 International Standard. In the case of any inconsistencies
between the NACE MRO175/ISO 15156 International Standard and the guidance
provided in this document, the International Standard should be adhered to.
Report of HSE regarding Corrosion Management and
Control in Offshore Oil&Gas - The aim of this document has
been to capture "best practice" from industry on corrosion management for
offshore processing facilities into a single document that will be in the public
domain. Whilst the many of the problems and solutions described in this report
are applicable to all aspects of oil & gas production, including design,
installation, production and transportation for onshore and offshore facilities,
the report is focused on operational aspects for offshore process plant and
facilities. Corrosion management also covers other integrity risks, including
those from stress corrosion cracking, embrittlement, erosion, etc., as well as
“simple corrosion” (i.e. general, pitting and crevice corrosion).
- This guide is intended to enable OSD
inspectors to make consistent judgement on the extent of external corrosion
related to the installation’s hydrocarbon systems. The guide identifies a sample
of six common forms of external corrosion and provides information on: n where
to look; and n what to look for. The six areas of concern are: n corrosion under
insulation (CUI); n firewater mains and deluge system; n flanges and plant
bolting; n valves; n pipe supports and pipe coatings; and n threaded plugs.
Report of HSE on Corrosion Control and Corrosion
Protection in Offshore and Oil&Gas - This Offshore
Technology (OT) Report provides technical information on the protection of
Offshore Installations against corrosion. It is based on guidance previously
contained in Section 12 of the Fourth Edition of the Health and Safety
Executive’s ‘Offshore Installations : Guidance on Design, Construction and
Certification’(1) which was withdrawn in 1998. As discussed in the Foreword,
whilst the text has been reformatted for Offshore Technology publication, the
technical content has not been updated. The appropriateness and currency of the
information contained in this document must therefore be assessed by the user
for any specific applicationA
Guideline To The Successful Use Of Duplex Stainless Steels For Flowlines
Article on Selection and use of Duplex Materials
in Offshore Oil&Gas, design limits for Duplex Stainless SteelPerformance
of Duplex Stainless Steels in Hydrogen Sulphide Containing Environments
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