Sarah Etubus - Wood Group Integrity Management (visitor)
Stephen Andrews –
Jan Przydatek - Lloyd’s Register EMEA
The Chairman, Robin
Oakley (QinetiQ), opened the meeting.
1.1 ‘Advances in Copper Alloy Aquaculture Cages’, Carol Powell, Copper Development Association & Langley Gace, International Copper Association, New York
in the Understanding of an Umbilical Local Environment’, Thierry Cassagne, Total
1.3 ‘Preferential Weld Corrosion in a Gas Compression System’, Dave Moore, Lloyd’s Register EMEA, Aberdeen
2.1 The MCF Chairman explained that the MCF would be celebrating
its 25th Anniversary in 2013 and the committee were looking into ways
to mark this event.
He drew the attention of the meeting to the planned Pipeline Protection, ‘Hot’ Topics and Marine Corrosion Conference, Edinburgh 15 – 18 October 2012. This conference is being organised by NACE and BHR, and the MCF was looking into ways of becoming involved in some way with the ‘Marine Corrosion’ part. Details on the news page of our website.
Charlie Barraclough (Commtech Associates)
initiated a discussion on the need to inlay 22Cr duplex flange ring grooves in
subsea service. He explained the background which was that CS flanges for
subsea service have the mating face or ring groove inlaid with 625 to prevent
local crevice corrosion due to the inability of CP to function in the crevice.
22Cr is generally not sea-water resistant at above ambient temperatures, and the
fluids inside the pipe may be at 50o to 100 o C. For
economic reasons a new generation of clients are currently using 22Cr for
flowlines and manifolds after the failures of the 90s and 00s.
It is apparently quite common to find 22%Cr duplex stainless
steel flanges being operated in seawater with internal fluids at 50°C-90°C.
Many operators are saying that cladding is not necessary, but the risk of
failure of these flanges would be reduced by their being clad with 625.
There was a discussion about the degree in which cathodic protection can hinder
initiation of crevice corrosion. If the CP system is switched on from the
start of deployment, then the extra protection from cladding may not be
necessary. Comparison of the corrosion resistances of the different nickel
alloys used in cladding was also spoken about. 825 is often found to have
not dissimilar corrosion performance in seawater to 316 (their PRENs are very
similar) and 718 has been known to exhibit
crevice corrosion. It was suggested that the known influence of biofouling
in causing initiation of crevice corrosion could explain this, as biofilms could
be picked up during transfer of components with an ROV.
Carol Powell (CDA)
reported on the joint EFC/NACE International Publication. 'The Corrosion
Performance of Metals for the Marine Environment - a Basic Guide’. Maney
Publishing have now published this book, which is EFC Publication No 63.
The National Metals Technology Centre (NAMTEC) at Rotherham are bringing the authors and other specialists together for a 1-day seminar on 30th May 2012: Metals and their Corrosion Behaviour in Marine Environments, aimed at giving practical guidance in the selection and use of steel and stainless steel as well as alloys of copper, aluminium, nickel and titanium, and also specifically address the special galvanic requirements that arise where metals are used in combination. Each delegate will receive a complimentary copy of the book as a key reference source in the future. http://www.namtec.co.uk/event/show/74
3.1 ‘Integrating Mathematical Modelling with
ROV Survey Data to Improve Interpretation, and Provide Input to Ongoing CP
Strategies’, Tim Froome, BEASY
3.2 ‘QA/QC Tools to Ensure the Quality of Duplex Stainless Steel Components’, Roger Francis, Rolled Alloys
Chairman closed the meeting at approx. 4:30 pm
meeting was followed by a meeting of ICorr, Aberdeen branch:-
MCF home page