The application provides a double-
machine double-stage screw
refrigeration compressor unit special for ground freezing, which comprises a low-pressure stage compressor, a low-pressure stage variable frequency motor, a plate-and-shell
heat exchanger, a high-pressure stage compressor, a high-pressure liquid accumulator, an evaporative condenser, a high-pressure stage
power frequency motor, an oil separator, a hot
siphon oil cooler, an
oil pump, an oil fine filter, a brine pump, a brine
pool, a hot
siphon evaporator, a
throttle valve and a control console. The double-
machine double-stage screw
refrigeration compressor unit special for ground freezing combines the variable frequency technology and the unique features of the double-
machine double-stage screw compressor
unit operation, can realize flexible adjustment of the volume ratio of the high-pressure stage compressor and the low-pressure stage compressor at different temperature points, reaches the highest efficiency, improves the refrigerating capacity at the medium temperature stage, reduces the use cost, improves the
motor efficiency and the refrigerating capacity at the low temperature stage, shortens the freezing time while saving energy, and is convenient for dismounting, installing and transporting.