Preface

The Vacuum system when fully operational becomes a rather massive heat load.
The thermal budget breaks down as follows:

• Cryopump helium system: 2.5kW
• Bell Jar during Vaporization: <5kW
• E-Beam Source: ~2-10kW

Issues with current setup:

• Improvised, not designed as well as it should.
• Poor controllability, only one loop for all systems.
  • This may not be a bad thing, but as of now the Helium compressor is in parallel with the rest of the system, causing a cooling imbalance.
• No Proper Reservoir, the system suffers severely from trapped air bubbles.
• BIG ONE: The current reservoir pump has a Pressure Reservoir, this coupled with the flow restrictions in the system allows ~6L of water to be stored as a pressurized holdoff, that releases when the system turns off.
  • This MUST be removed, it is one of the reasons for the air inclusion, pressure issues and recent water leak. It also takes up large amounts of space.
• No flow metering. We have rotary flow meters with electronic readout available, they should be included.
• No Proper temperature readouts.
• BIG ONE: Insufficient fan pressure to cool the radiator properly.
  • Stronger fans must be used.