Using the helium mass-spectrometer leak detector to detect the leak of seams between the tube and face-flange and measure the total leakage rate are introduced in this paper.
J - t loop is precooled by two - stage pulse tube cryocooler in order to obtain liquid helium temperature.
系统设计用两级脉冲管制冷机预冷小型节流制冷机以获得液氦温区环境。
3
The authors give a novel conception that in order to increase the cooling capacity of a pulse tube refrigerator at 80K temperature range, refrigerant mixtures are introduced instead of pure helium.