[Kimura and Araki (KEK)]
The temperature of the piping in the compressor for the duct shield cryo-cooler at BS side (Xfs) was measured.
The results are shown below.
Row 2 is without circulator.
Row 3 is one circulator
Row 4 is one circulator and spot cooler added.
We confirmed the temperature of the capillary tube and the base of the compressor is reduced by about 6°C due to the enhanced cooling.
As a result, a margin was secured against the thermal switch attached to the gas outlet piping, which is approximately 93°C..
| 20/Dec. | 9:58~10:10 21/Dec. | 15:14~15:30 21/Dec. | |
| Items | without circulator | one circulator | Four circulators and one spot cooler added |
| Helium gas supply (°C) | 21.9 | 21.3 | 22.7 |
| Helium gas return (°C) | 24.3 | 23.9 | 24.0 |
| Adsober OUT (°C) | 22.5 | 21.5 | 22.8 |
| Adsober IN (°C) | 21.1 | 21.0 | 22.1 |
| Oil separator IN (°C) | 20.1 | 19.6 | 19.8 |
| Oil separator OUT (°C) | 20.9 | 20.5 | 21.1 |
| Heat exchanger He IN (IN-1) (°C) | 89.1 | 78.3 | 83.9 |
| Heat exchanger OIL IN ( IN-2) (°C) | 89.2 | 85.5 | 89.0 |
| Surface temp. of the main unit (°C) | 65 | 65 | 55 |
| Capillary tube temp. for oil return (°C) | 68.8 | 73.3 | 60.7 |
| Gas outlet piping temperature (°C) | 93.4 | 93.5 | 87.6 |
| Water inlet temp. (°C) | 19.7 | 18.7 | 18.3 |
| Water outlet temp. (°C) | 25,1 | 24.5 | 24.3 |
| Psupply (MPa) | 2.28~2.32 | 2.28~2.32 | 2.30~2.33 |
| Preturn (MPa) | 0.648~0.689 | 0.662~0.738 | 0.655~0.710 |
| Pdeff (MPa) | 1.63~1.63 | 1.618~1.582 | 1.645~ 1.620 |