1. Force balance:
   • Single-screw air compressor: The forces experienced by the screw are automatically balanced radially and axially. The star wheel teeth bear the gas forces and require sufficient strength and stiffness.
   • Twin-screw air compressor: The screw rotors bear larger radial and axial gas forces, requiring the screws to have sufficient strength and stiffness.
2. Manufacturing cost:
   • Single-screw air compressor: The screw and star wheel bearings can use ordinary bearings, resulting in lower manufacturing costs.
   • Twin-screw air compressor: Due to the higher loads on the two screw rotors, higher precision bearings are required, leading to higher manufacturing costs.
3. Reliability:
   • Single-screw air compressor: The star wheel is a vulnerable component that requires regular replacement, in addition to high material requirements.
   • Twin-screw air compressor: There are no vulnerable parts in the twin-screw air compressor, and it can operate without failures for 40,000 to 80,000 hours (with regular major overhauls).
4. Efficiency:
   • With increasing operating time, the wear of the star wheel in single-screw air compressors can lead to reduced airflow and decreased efficiency.
5. Noise and vibration:
   • The noise and vibration levels of single-screw and twin-screw air compressors are generally similar.
6. Processing equipment:
   • Single-screw air compressors lack mature specialized processing equipment, which may result in less stable product performance. Twin-screw air compressors have dedicated screw milling and grinding machines, ensuring stable product performance.
7. Operation and maintenance:
   • The daily operation and maintenance of single-screw and twin-screw air compressors are generally similar.
8. Applicability:
   • Single-screw air compressors are suitable for applications requiring high discharge pressures.
   • Twin-screw air compressors, due to rotor stiffness and bearing load limitations, are typically limited to medium and low pressure ranges, with discharge pressures generally not exceeding 4.5 MPa.

From a structural standpoint, the manufacturing process of twin-screw compressors is more complex than that of single-screw compressors. In a new machine state, the efficiency of single-screw and twin-screw compressors is similar.