Modified Claude Liquefaction Cycle Helium Liquefier

A Large cryogenic helium liquefaction plant adopts helium turbine reverse Bratton refrigeration cycle to obtain the corresponding refrigeration capacity. High-pressure helium is obtained through helium compressor first, part of high-pressure helium is expanded and cooled in turbine expander, and the remaining high-pressure gas is cooled step by step in multistage heat exchanger, and finally liquid helium is obtained by throttling through Jiao Tang throttle valve, and the obtained liquid helium is directly output as product. Such refrigeration equipment is called a helium liquefier.

①Helium compressor     ②4.5K cold box     ③Liquid helium dewar       ④Oil removal system     ⑤Control cabinet    ⑥Coaxial transfer line

⑦LN2 tank              ⑧Helium buffer tank

The basic composition of a 4.5K helium refrigerator/liquefier system consists of several parts as shown in Figure 2：

1. The circulating air source system includes: 

helium compressor, helium oil separator and helium storage tank

2. 4.5K cold box：

The 4.5K cold box is a vacuum adiabatic cold box, which contains a multistage heat exchanger, a helium turbine expansion machine, an internal adsorption cylinder, a low-temperature valve, measuring elements and other components.

3. Liquid helium storage system：

It includes liquid helium dewar, coaxial transmission tube from cold box to liquid helium dewar, and infusion tube for transferring liquid helium

4. Control system：

Including control system hardware, software, configuration and remote control.

5. Public facilities：

Including liquid nitrogen storage tank, instrument air system, cooling water system.