Development of 4 K pulse tube cryorefrigerators at cryomech

摘要: Cryomech, Inc. has continued the development of two-stage 4 K pulse tube cryorefrigerators. To address concerns customers with vibration levels due to stretching in tubes, a elimination apparatus reduced maximum displacement from 25 μm <3 μm. The PT405, 0.5 W @4 K, was modified into model PT407, by using CP970 Compressor Package increasing input power 4.7 7.2 kW. It provides 0.72 @4.2 34 @55 K. A new model, PT410, been developed cooling capacities 0.83 38 @45 for 8.0 kW input. PT410 is driven one Package. With changing flow impedances, also can provide 1.05 and simultaneously 28 @56 again power.