| AVS 61st International Symposium & Exhibition | |
| Vacuum Technology | Wednesday Sessions |
| Session VT-WeA |
| Session: | Accelerator and Large Vacuum Systems II |
| Presenter: | Robert Pearce, ITER Organisation, France |
| Authors: | R. Pearce, ITER Organisation, France M. Dremel, ITER Organisation, France L. Worth, ITER Organisation, France L. Baylor, Oak Ridge National Laboratory S. Meitner, Oak Ridge National Laboratory |
| Correspondent: | Click to Email |
ITER is under construction in the south of France in order to demonstrate the feasibility of fusion as a clean power source. It is one of the world’s largest scientific and engineering collaborations. The civil structures, to house the ITER machine, are progressing, and the key systems and components are moving from design to manufacturing.
The ITER vacuum system will be one of the largest, most complex vacuum systems ever to be built. There are a number of large volume systems including: the cryostat (~ 8500m3), the torus (~1330 m3), the neutral beam injectors (~180m3 each) and a number of lower volume systems including: the service vacuum system, diagnostic systems, and electron cyclotron transmission lines. In total there are more than 400 vacuum pumps of 10 different technologies required to pump the systems. The most demanding vacuum pumping applications are served by 18 large cryogenic pumps of 3 distinct custom designs.
The ITER vacuum vessel and cryostat are to be pumped by a total of 8 cylindrical cryo-sorption pumps with integral 800 mm all metal vacuum valves. The “build-to-print” design of these pumps has been optimised and finalised and the first pump is being manufactured.
The ITER neutral beam systems are each pumped by a pair of open structure panel style cryo-sorption pumps with a length of 8 m, and height of 2.8 m. They should achieve a pumping speed of 4500 m3/s for hydrogen. The final design of these pumps has involved development of new fabrication methods so as to significantly reduce the cost and manufacturing time for the thousands of cryo-panels and thermal shields within the pumps. The design is ready for manufacture, with the first pump destined for the ITER neutral beam test facility (MITICA).
During plasma operations, to pump the mixture of gasses originating from the regenerations of torus and neutral beam cryo-pumps, the roughing system will utilize 6 cryogenic viscous flow compressors (CVC). The principle of the CVC is that it will cryogenically condense hydrogen isotope mixtures, while providing first stage compression of helium ash originating from the fusion process. Each CVC is designed for throughputs of 200 Pam3/s and consists of a tube heat exchanger housed in a cryostat of diameter ~1 m and height 2.5 m. The very novel nature of this pump requires a full size prototype, which has been manufactured and will go through a test campaign.
In this paper an overview is given of the ITER construction. Examples of the cryo-pump ‘value engineering’ and design optimization for manufacturing are given. Progress and challenges in the “First of a Kind”(FOAK) vacuum pump manufacturing are given.