Member Profile: 3 questions to Philippe Pottier, Managing Director of Siem Supranite

  • 16.11.2021
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Siem Supranite is the story of a Franco-British encounter: in the aftermath of the Second World War, a member of the Free French Forces joined forces with British industrialists wishing to develop in France; Siem Supranite was born. The Parisian SME, specialising in the design of seals and braids, now employs 50 people and supplies various industries: chemicals, oil & gas, food processing, military and, of course, nuclear. Fifteen years ago, it became a subsidiary of the Flexitallic group, a "pocket-sized multinational", says Philippe Pottier, its Managing Director, whom we interviewed.

What are Siem Supranite's activities in the nuclear industry?

Nuclear power now accounts for 30 to 40% of our turnover; we mainly supply EDF and its equipment suppliers, but also Framatome and Orano for its fuel cycle installations. It must be said that Siem Supranite was involved in the nuclear industry from the very beginning. We equipped the steam generators of Westinghouse power plants, which France licensed to build pressurised water reactors. Our products have therefore been present in all French nuclear power plants since their inception.

Our strength in the nuclear industry is that we are a company prepared to invest in the long term, to offer our customers solutions adapted to their needs, but also to changes in regulations: for example, we were the first to produce a PMUC expanded graphite ribbon without sulphur and chlorine, elements that were conducive to the corrosion of equipment in EDF power plants. Similarly, even before the ban on asbestos, a material that was once omnipresent in all sealing solutions, we were able to develop asbestos-free products. So when asbestos was banned in 1996, Siem Supranite was able to supply EDF immediately. 

The second quality of Siem Supranite is its good knowledge of the French nuclear fleet, but also its proximity and its capacity to intervene: We have built up a network of engineers and technicians throughout the country, so that we can advise and intervene on each installation in less than an hour. Our mission is to offer plant maintenance engineers the opportunity to sleep soundly and peacefully!

What's the latest on Siem Supranite?

Siem Supranite's news revolves around two major innovations in its product range: on the one hand, the Flexitallic group took advantage of the centenary of the Flexitallic spiral wound gasket, created in 1912, to revolutionise the concept by proposing a gasket that meets the needs of the field: the Change Gasket, which benefits from a high elastic recovery, low tightening and the robustness necessary for its handling.

In addition, Siem Supranite developed an innovation to meet a specific request from EDF: the electricity company was looking for a product capable of reducing friction on its valves, resistant to irradiation of 4 MGy and PMUC. To meet this need, Siem Supranite designed a low friction press kit: Supranite NGN 03 AS non-dispersive graphite tape, which improves the performance of valves installed in power plants, both in terms of operability and safety. Its specificity is that it reduces friction and does not release any lubricant.

What are the prospects for Siem Supranite in the medium and long term?

We are witnessing a real change in attitudes towards nuclear power: it is now increasingly recognised as the low-carbon energy source par excellence. As a manufacturer of products that are crucial to the safety of nuclear installations, we must therefore maintain the level of trust placed in us by our customers and equipment manufacturers, by maintaining an increasingly high level of requirements.

In France, we are beginning to be approached about new reactor projects, whether it be the EPR2 or the SMR. Three years ago, we also started working on specific equipment for the ITER project.

In addition, we have a strong international presence in the Flexitallic group. Our factories in China, Germany, the United States, Canada, Italy, Belgium and Thailand give us a very detailed view of the European, North American and Asian markets. We export a lot to China, and not just for the Taishan EPRs. In the UK, we have good coverage of the HPC field thanks to our strong link with Flexitallic UK. We are also already consulted on Sizewell. We are also present in the United Arab Emirates, the United States and Poland.

In short, the dynamism we are currently seeing in the nuclear industry, both in France and internationally, is opening up good prospects for us.

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