When gas is compressed, a large amount of compression heat is generated. The greater the compression ratio, the greater the compression heat. A large amount of mechanical energy is converted into thermal energy but fails to be converted into compression energy. The two-stage compression process completes compression in the first and second stages respectively. Reduce the compression ratio, reduce compression heat, and significantly reduce the load on each stage of the rotor.
According to the theory of engineering thermodynamics (the higher the temperature, the lower the gas density and the higher the power consumption), through inter-stage oil injection cooling, the gas heat is exchanged and taken away in time, making the first-stage compression and the second-stage compression close to isothermal compression. The temperature difference between thermal expansion and contraction is small, and at the same time the load on the cooling system is reduced, reducing the energy loss and consumption of the cooling system and improving efficiency.
The male and female rotors of the screw host are non-contact, and there will be a backflow and moisture leakage area between the screw host and the cavity. The greater the compression ratio of the screw host, the greater the return leakage. Due to the reduced compression ratio of the two-stage compression host, the return flow loss is reduced and the efficiency is improved.