Efficient 10 K Pulse Tube Cryocoolers

Abstract

Two 10 K pulse tube cryocoolers, Models PT805 and PT810, have been developed and commercialized at Cryomech to provide cooling from 8 K to 20 K. The PT805 provides 3.5 W at 10 K and 48 W at 80 K, simultaneously, for 4.6 kW power input. The PT810 provides 10 W at 10 K and 40 W at 49 K, simultaneously, for 7.6 kW power input. These pulse tube cryocoolers have almost the same efficiency, cooling capacity, and cooling speed as that of 10 K Gifford-McMahon (GM) cryocoolers. A test demonstrated that the two-stage pulse tube cryocooler is less sensitive to the air contamination than 10 K GM cryocooler. The pulse tube refrigerators developed at Cryomech are expected to have mean time between maintenance (MTBM) > 5 years. The PT810s have been used for cryopumps and demonstrate their advanced features in the field.