Experimental study on the sealing clearance between the labyrinth sealing displacer and cylinder in the 10 K G-M refrigerator

摘要

The labyrinth sealing displacer has been optimal designed to improve the operating stability and life-time of 10 K G-M refrigerator. The displacer was made of stainless steel 304 or inconel 718, coated with PTFE on its outer surface. Compared to the traditional piston-ring sealing displacer, the sealing clearance between the ridge of the labyrinth sealing displacer and cylinder is critical to the cooling performance of the G-M refrigerator. The displacers with different sealing clearances were experimentally studied, and the optimal clearance was given. The effects of the materials of the displacers and the system charge pressures on the performance of the labyrinth sealing were also tested and analyzed.