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Areva Le Creusot ASN
ASN images
steam generator  channel heads ASN

On the 28th of June, the French Nuclear Regulator, ASN, announced that some nuclear reactor steam generators made at Areva-Le Creusot Forge “could contain an anomaly similar to that affecting the Flamanville EPR vessel“. They explain that”These steam generator channel heads are hemispherical forged parts constituting the lower part of the steam generators. They contribute to containment of the primary system water. These components are essential for safety. The quality of their design, manufacture and in-service monitoring is therefore extremely important.” They also tell us that: “analyses of the other forged components making up the vessel, the pressuriser and the steam generators and liable also to be concerned by this anomaly are ongoing.” (See ASN News Release below). While the French Regulator works, the US NRC twiddles their thumbs waiting to see what the liable party, Areva, will tell them. And, instead of reporting this new news they reblogged an old post about a computer program called SATANS (not a joke): https://web.archive.org/web/20160630061133/http://public-blog.nrc-gateway.gov/2016/06/29/refresh-satans-code-the-early-years-of-accident-models/ Was this to underline the US NRC’s devil may care attitude? The ASN has their hands full regulating the French reactors. They cannot do other regulator’s work for them. Ultrasonic inspection is required, says ASN. The Belgium regulator is opening a judicial investigation regarding the parts: http://www.fanc.fgov.be/fr/page/homepage-agence-federale-de-controle-nucleaire-afcn/1.aspx Swiss Beznau appears at risk. While they appear to have inspected the pressure vessels with ultrasound, did they inspect the steam generators? France, Beligium, Switzerland, Sweden, Spain, Slovenia, Brazil, South Africa, South Korea, the US, and China may be at risk. The UK (Sizewell B) apparently doesn’t have an Areva steam generator, but may have other defective parts.

In the US, nuclear reactors having potentially defective Le Creusot-Areva steam generators include: Prairie Island 1 and 2 (along with Reactor Pressure Vessels); Callaway; Arkansas One (along with reactor pressure vessel closure heads-lids); Salem; St. Lucie (along with RPV closure heads-lids, Pressurizers); Three Mile Island (along with RPV closure heads) (See Greenpeace France, Briefing http://grnpc.org/IgNdG ; AREVA – Société Générale / Investor day Burgundy – April 9, 2009)

Prairie Island also has defective ABB (Swiss-Swedish) breakers: http://www.nrc.gov/reading-rm/doc-collections/event-status/event/2016/20160606en.html

Based on a Greenpeace France Briefing and a 2009 Areva document, other reactors which have Creusot Steam Generators:
Sweden: Ringhals – Steam generators in reactors 3 and 4 have been replaced with Creusot-made parts.
Switzerland: Beznau 1 and 2 (replacement) steam generators (and reactor pressure vessels) were supplied by Creusot.
Belgium: Tihange and Doel (replacement) steam generators (also vessel closure heads and pressurisers)
Spain: Asco and Almaraz (replacement) steam generators
Slovenia: Krsko (replacement) steam generators from the site.
While the UK has Areva-Le Creusot parts, they do not have a steam generator from there, it seems.
Brazil: Angra II (replacement) steam generators.
China: possibly Guangdong 1 and 2 reactors, Ling Ao 1, 2, 3 and 4 reactors
South Korea possibly Ulchin 1 and 2 reactors.
South Africa possibly Koeberg 1 and 2 reactors
Greenpeace France, Briefing http://grnpc.org/IgNdG
AREVA – Société Générale / Investor day Burgundy – April 9, 2009

France: Le Blayais NPP, reactor 1, Bugey NPP, reactor 4, Chinon NPP, reactors B1 and B2, Civaux NPP, reactors 1 and 2, Dampierre NPP, reactors 2, 3 and 4, Fessenheim NPP, reactor 1, Gravelines NPP, reactors 2 and 4, Saint-Laurent-des-Eaux NPP, reactors B1 and B2, Tricastin NPP, reactors 1, 2, 3 and 4

List of AREVA customers as of 2009. So, it may be longer. This list is for Areva’s Chalon-St. Marcel facility near Le Creusot. They and Jeumont Schneider assemble the Creusot Forge parts. It corresponds to the Greenpeace France list.
list of Areva  customers Chalon St. Marcel Areva
AREVA – Société Générale / Investor day Burgundy – April 9, 2009“, p. 56 https://web.archive.org/web/20150421153404/http://areva.com/finance/liblocal/docs/PDF/2011/Investor_Day%20Equipment%20BU%20-%20April%209,%202009.pdf It says on p. 54 that they have delivered 309 Steam Generators and 47 are on order; 77 Reactor Vessels & Closure Heads and 3 on order, 73 Replacement RVCHs and 3 on order, 67 Pressurizers and 5 on order. This suggests an even more widespread problem.

From the France’s regulator the ASN (note that EDF is the French State owned utility; Le Creusot Forge is owned by French State owned Areva):
Certain EDF reactor steam generators in service could contain an anomaly similar to that affecting the Flamanville EPR vessel
28/06/2016 12:00 pm Note d’information
Steam generator channel head

The analyses carried out by EDF since 2015 conclude that certain steam generator channel heads could contain a zone comprising a high carbon concentration which could lead to lower than expected mechanical properties. These steam generators equip 18 reactors of the 900 and 1450 MWe plant series.

These analyses were performed at the request of ASN to identify the equipment of the reactors in service which could be affected by an anomaly similar to that in the Flamanville EPR vessel.

ASN asked EDF to demonstrate the mechanical strength these channel heads, which were manufactured by Creusot Forge and by a foundry in Japan (JCFC). ASN considers that the initial demonstration data provided, on the basis of which EDF kept the equipment concerned in service, need to be confirmed. It therefore asked EDF to carry out additional investigations on the channel heads concerned.

These steam generator channel heads are hemispherical forged parts constituting the lower part of the steam generators. They contribute to containment of the primary system water1. These components are essential for safety. The quality of their design, manufacture and in-service monitoring is therefore extremely important.

Furthermore, analyses of the other forged components making up the vessel, the pressuriser and the steam generators and liable also to be concerned by this anomaly are ongoing. ASN will make sure that they contribute to complete experience feedback from the anomaly detected on the Flamanville EPR vessel and that all possible consequences for the safety of the installations are identified.

These elements will be presented at the 24th June 2016 meeting of the Advisory Committee for nuclear pressure equipment. Representatives from the OPECST, HCTISN and ANCCLI have been invited to attend as observers.
Reactors liable to be affected:
* Le Blayais NPP, reactor 1
* Bugey NPP, reactor 4
* Chinon NPP, reactors B1 and B2
* Civaux NPP, reactors 1 and 2
* Dampierre NPP, reactors 2, 3 and 4
* Fessenheim NPP, reactor 1
* Gravelines NPP, reactors 2 and 4
* Saint-Laurent-des-Eaux NPP, reactors B1 and B2
* Tricastin NPP, reactors 1, 2, 3 and 4
1. Needed to cool the nuclear fuel

https://web.archive.org/web/20160701034342/http://www.french-nuclear-safety.fr/Information/News-releases/EDF-reactor-steam-generators-in-service-could-contain-an-anomaly

Additional info from France’s regulator the ASN:
Technical notice: technical clarifications on the manufacturing anomalies liable to affect the steam generator channel heads

Steam generator channel head

A steam generator (SG) is a heat exchanger between the water in the primary system, raised to high temperature (320°C) and high pressure (155 bars) in the reactor core, and the water in the secondary system which is converted into steam and drives the turbine. Each steam generator comprises several thousand U-tubes, which allow the exchange of heat between the water in the primary system and that in the secondary system, to produce the steam driving the turbine. The 900 MWe pressurised water reactors comprise three steam generators, while the higher power reactors comprise four.

The steam generators are equipment important for safety. They form a part of the second and third containment barriers.

The channel head is a steel component with the shape of a portion of a sphere, situated at the base of the steam generator. It contributes to the containment of the water in the primary system.

The channel heads installed in the nuclear power reactors were manufactured using different technologies. The channel heads liable to be concerned by the anomaly were forged from solid, or “conventional” steel ingots.

Carbon concentration anomaly in the steel

In the central zone of the channel heads, the analyses conducted revealed a high carbon concentration. This is called carbon segregation and should normally be eliminated from the final part during the forging operations, which was not the case with the manufacture of the heads liable to contain an anomaly.

This mechanical properties of this zone, in particular its resistance to crack propagation, are lower than anticipated.

Investigations requested by ASN

At the request of ASN, EDF is currently carrying out investigations into the channel heads concerned, the aim of which is to:

– precisely locate the zone with the high carbon concentration. This is done by means of non-destructive measurements on the outer surface; – check that there are no defects in the head (cracks in particular) liable to lead to fracture of the part. These checks are carried out using ultrasound inspections.

EDF also intends to carry out a test programme on available representative channel heads.

ASN will review the results of the investigations carried out by EDF to ensure that the equipment is able to perform its safety functions.
https://web.archive.org/web/20160701034440/http://www.french-nuclear-safety.fr/content/download/103727/765440/file/RW-2016-06_NT_segregations_parc_V4_revuDEP.pdf

Emphasis added throughout.