Commissioning of the new 1 kW class refrigerator for superconducting LINAC at IUAC

For the LINAC booster project 5 cryostats with 27 resonators have been commissioned in phases. The total measured heat load on cryostats and distribution system together is 350 W at 4.4 K. At present total heat load is managed by the 15 year old LHe refrigerator from C CI, USA which has a capacity of approx. 300 W @ 4.4 K. A new LHe refrigerator of higher capacity (750 W at 4.4K) with automation features from LINDE Kryotechnik, has been recently commissioned. Also new LHe distribution system connecting the new refrigerator with the existing distribution system has been commissioned. This paper will highlight the efforts and results in commissioning both these systems and also report a set of pressure drop data received from 1^st set of experiments over the entire LHe distribution system with preliminary analysis of the data obtained. (author)