on our own words

Credit © ITER Organization

ITER, Divertor Cassette Body

Prototype for cutting-edge science project – world’s first fusion reactor

A Divertor Cassette Body (DCB) prototype weighing 4.7 metric tonnes was ordered from Suisto Engineering for the ITER Project. The DCB is a demanding welded and machined structure made of austenitic steel for the world’s first fusion reactor. The order also included assembly components for the DCB and the design and production of the DCB transport frame.

The challenge posed by the design and implementation work for the ITER Project is in a league of its own. Because the world’s first fusion reactor is involved, the components designed and produced for it are also naturally unprecedented. Just submitting the tender was a demanding project that was completed on a tight schedule. The tender documentation itself amounted to 800 pages.

The ITER Project adheres to some of the strictest quality standards and quality management procedures in the world, with extremely strict requirements for project management and traceability throughout the entire supply chain. The amount of documentation required is immense because the end product must be traceable down to each and every part. The traceability requirement applies to everything: the materials and the production of the product itself, starting with the primary production of the original materials and including all the tests and inspections conducted along the way.

Uniquely challenging project

Suisto Engineering’s proactive and solution-oriented approach helped overcome the technical challenges of the Divertor Cassette Body Project. The technical risks were already minimised during the design phase to ensure that things ran as smoothly as possible during the production phase.

Finding and taking factors that would improve manufacturability into account were emphasised in the production planning. It was also important to take the requirements of the future serial production of 60 pieces into account during the prototype phase because the detail design and production method of the final product, along with other factors affecting the production, production costs and schedule, are mainly locked down during the prototype design.

The project management requirements during the Divertor Cassette Body Project, such as those related to budgeting, costs and schedule, were also unique. The strict quality control applied to Suisto Engineering and also the work done by its subcontractors. That is why the preliminary planning, work monitoring and control, setting and monitoring requirements, and reporting required special efforts and attention. The project plan, quality plan and project management procedures were under constant assessment and were developed further based on the experience gained. Scalable project management procedures and tools, which were created for and tried and tested during the ITER Project, will be utilised in the future in other demanding Suisto Engineering projects.

Developing expertise through challenges

Suisto Engineering’s experience increased immensely during the Divertor Cassette Body Project. In technical competence, Suisto Engineering gained more experience with the challenging materials used in the production and the development and utilisation of top-level welding and inspection methods, measuring a product to meet high precision requirements, measurement planning and precision simulation, and the design, development and simulation of machining.

Design and descriptive competence with various procedures, including quality procedures, project management, testing, production, measurement and inspection, rose to a whole new level. The learning was further complemented by improvement in the maintenance of high levels of cleanliness purity and in vacuum competence. In addition to Suisto Engineering, many subcontractors also got the opportunity to increase their competence in the jointly executed project.

Unique opportunity

Three other European operators in addition to Suisto Engineering are also producing Divertor Cassette Body prototypes. All companies that succeed in supplying a prototype are allowed to compete for the delivery of the 60-piece DCB series. On top of any additional commissions, just participating in the ITER Project is a unique opportunity and show of confidence in a Finnish operator.

“With the ITER Project, the competence of Suisto Engineering has risen by several orders of magnitude. The experience gained during the project, which lasted a few years, is the equivalent of the knowledge and experience acquired during up to a decade of normal deliveries.”
Mikko Jokiranta
Project Manager, Divertor Cassette Body Project


ITER Project

The ITER Project is a large-scale international science and mechanical engineering project, whose main funder is the European Union. The motive for developing fusion energy is that, if successful, it would significantly relieve humanity’s energy problem by producing clean, emission-free energy and controlling carbon dioxide emissions; the fuel would, in practice, be extracted from seawater, and the fusion power plant’s reaction only produces helium as waste, along with some low-level waste that requires disposal.

Once the ITER machine is completed, the plan is to build a demonstration reactor that generates power for the grid in order to verify the viability of commercial production of fusion power. The preliminary planning of the demonstration reactor is under way. If the project is successful, the plan is to have it operational by 2050.