R&D of Insulating and Vacuum Pressure Impregnation Equipment for PF1 Coil Double Pancakes

The PF1 coil is one of six poloidal field coils of the ITER magnet system. The PF1 coil winding is constructed from eight double pancakes (DPs), which are plane cylindrical solenoids of about varnothing 9 ×0.1 m in size and about 20 ton in weight. The monolithic electrical insulation of the PF1 coil is designed under ITER requirements and consists of the conductor multilayer turn insulation, the interlayer insulation of the pancakes, and the ground insulation of the winding. Vacuum pressure impregnation (VPI) with the epoxy resin provides the insulation strength after high-temperature curing. This paper presents the research and development results concerning insulating and VPI equipment for PF1 coil insulating. It involves the 12-roll insulation device for lapping of polyimide and glass tape layers, the vacuum chamber for double pancake impregnation and curing, and automated devices and heaters for mixing and supply of the resin under necessary vacuum and temperature conditions. All equipment has been successfully tested using DP mock-ups. The biggest one was manufactured as a full-scale DP sector. Following modeling, the standard insulation samples were taken from the mock-up to prove the mechanical properties of the insulation to meet the ITER requirements. The test results are also given in this paper.