Cascade refrigeration is widely used in the heat treatment process of industrial products and the cold treatment of metals, and is widely used in industries such as military, aviation, aerospace, chemical, pharmaceutical, and mechanical manufacturing. Some process reactions require deep cold environments below 50 ℃. To ensure reaction conditions, the reaction system is often cooled to -60 ℃ or even lower, and corresponding refrigeration and cooling measures must be taken. Cascade refrigeration has significant differences in unit design compared to conventional units due to its lower temperature, such as chillers, industrial chillers, freezers, and screw chillers
