Ice from poor vacuum inside jacket on 7/17/03

On 7/17/03 I found out that the cryocooler vacuum jacketed lines had vented 
following a power bump. The power bump tripped a breaker and the turbo stopped.
When our turbo stops, at the end of its slowing down process it vents the 
system opening a venting valve. I will try to fix this in the future by 
disabling the venting valve and replacing it with a manual valve. In the 
meantime, we should be careful to leave the pump unattended on critical 
beamline equipment. 

Fig 07-17.1. Picture of the vacuum jacketed line iced up after a failure
of the turbo pump. There was a noticable power bump today and the breaker #17
feeding the turbo pump tripped. The turbo vents when it turns off so the
jackets were unfortunately vented. This could have resulted in serious problems
with the cryocooler.

Fig 07-17.2. Another view of the iced up line.

Fig 07-17.3. Yet another view of the lines

Fig 07-17.4. View of the lines after repumping the jackets. The ice melted.

Fig 07-17.5. View of the lines after repumping the jackets.