Provided is a machine unit layout system that simplifies the layout of a compressor unit and an expander unit and is extremely effective in terms of not only the reliability of the entire machine but also maintainability. Two separate compressors, a low-pressure-side compressor and a high-pressure-side compressor (11A, 11b), are disposed on either side of a steam turbine (10). Two separate expanders, a low-pressure-side expander and a high-pressure-side expander (12A, 12B), are disposed outside the low-pressure-side and high-pressure-side compressors (11A, 11b). The steam turbine (10), the low-pressure-side and high-pressure-side compressors (11A, 11b), and the low-pressure-side and high-pressure-side expanders (12A, 12B) are coupled by rotor shafts comprising a single shaft. The torque distribution between rotator shafts is optimized.