Thousands of scientists, engineers and technicians have been involved in designing the world’s largest tokamak, since the late 1980s. The ITER experimental reactor, under construction since 2010, intends to demonstrate that hydrogen fusion, the energy of the Sun and stars, can be used as a sustainable energy source to generate electricity on a large scale. For more than ten years, CNIM has been contributing its expertise to the ITER programme in the following fields: the study, design, development and manufacture of highly secure handling solutions as well as the industrialization and manufacture of large-scale equipment with high added value.
So far, CNIM has been awarded nearly 20 contracts for which the industrial company is constantly investing to strengthen the expertise of its teams and its industrial facilities.
The recent contract to develop the manufacturing and production process for the nine pre-compression rings reflects CNIM’s pioneering spirit in meeting ITER’s technological challenges. These glass/epoxy rings are designed to reduce the fatigue incurred by toroidal field coils subjected to strong magnetic forces. The solution proposed by CNIM – a particularly innovative manufacturing process based on pultruded composite material* – has shown its worth in terms of technology and reliability.
* Pultrusion (a term made up of the words “pull” and “extrusion”) is a process for the continuous processing of composite tubes and profiles.
An unparalleled scientific and technological research facility such as ITER needs industrial partners who are not only outstanding experts in existing technologies, but also pioneers in the technologies of the future that we need right now. CNIM, which came up with a highly innovative, first-of-its-kind solution in response to one of our needs, is one of the project’s major partners and proved itself equal to the challenge: to pave the way for a new, secure energy source based on a virtually inexhaustible resource and with virtually no environmental impact.
Bernard Bigot, Chief Executive Officer, ITER Organization
In 2016, F4E * entrusted CNIM with the development of the manufacturing process and the production of three (6 + 3 spares) Pre-Compression Rings (PCRs), composite glass / epoxy rings to be used in the ITER reactor. Two years later, CNIM was tasked to produce another six. The PCRs will withstand particular very high stresses (up to about 500 MPa MPa in hoop,) and a temperature of 4K (-270°C) when ITER will be in operation.
*F4E is the EU organization managing the European contribution to ITER https://www.fusionforenergy.europa.eu/
At the end of 2012 the Franco-Italian consortium CNIM-SIMIC was awarded the contract to manufacture 70 radial plates. They will constitute the framework for the 18 toroidal windings needed to create a magnetic field strong enough to confine the plasma within the empty core of the ITER.
CNIM and SIMIC have therefore formed a partnership to pool their experience and thereby increase their productive capacity. Each partner is responsible for manufacturing 35 plates.
A set of tools is being built to ensure the successful handling and precise positioning of hundreds of extremely large components for the Tokamak*. The Sector Subassembly Tool (SSAT) developed by Korean, includes two tools. Both tools will be used to pre-equip the nine 40° sectors** of the Tokamak. CNIM is responsible for the on-site assembly of this extra-large tool rising 22 m tall and weighing 880 metric tons.
* A powerful magnetic field to confine a hot plasma in the shape of a torus.** Each Tokamak sector consists mainly of portions of vacuum chamber, heat shielding and two TF coils (superconductor magnets weighing about 400 metric tons).
In December 2016, ITER chose CNIM to engineer, manufacture and install special tools for the assembly of the Tokamak’s external components.
This five-year framework contract for Purpose Built Tools (PBT) includes various steps.
For the first part of the contract, CNIM designed nine types of special tools, some of which were capable of handling items 17-meters tall weighing 700 metric tons with a precision of about a tenth of a millimeter.