TFTR Vacuum Vessel heating/cooling systems

The two fluid systems that are used to cool the Tokamak Fusion Test Reactor (TFTR) Vacuum Vessel during normal operation and/or used to bake out the vacuum vessel are described. One system is called the Bellows Cooling System and the other is called the Vacuum Vessel Shell System. The Bellows Cooling System circulates 3600 CFM of gaseous nitrogen around the outside surface of the fourteen vacuum vessel bellows. This system is used for cooling purposes only. The Vacuum Vessel Shell System is an air system whose purposes are to cool the vessel during normal operation and to heat the vessel to 480 F, for the purpose of in situ bakeout. The system includes a 12,000 CFM air compressor that delivers 30 psia, 65 F coolant to the stainless steel jacket on the vacuum vessel. In the heating mode, the same system is used in a different configuration to supply hot air to the vessel. The air compressor's heat of compression is the only heat source. The vessel heat up rate is controlled by regulating the air temperature.