There was a possible power blackout on Nov 9 from 2 am to 4 am at builidng 182.
During the blackout, the vacuum pump for pumping the insulation vacuum of the cryogenic system was OFF.
Moistures were accumulated in the interlayer during these two hours, and now the vacuum insulation is not as good as before.
This causes some bubbles generating in the liquid delivery bellow and significantly reduces the fast recirculation speed. |