Product Overview
A two-stage rotary screw air compressor compresses air through two separate compression stages instead of completing the full compression ratio in a single airend. This configuration is commonly selected for industrial compressed air systems with continuous operating hours, significant air demand, and strict sensitivity to energy consumption.
Selecting the correct compressor requires evaluating actual air demand, operating pressure, load profile, ambient conditions, and annual running hours. A higher motor rating alone does not indicate a better match for an industrial application.
Technical Parameters & Specification Matrix
|
Technical Parameter |
Fixed-Speed Series (Model Range) |
Variable-Speed (VSD) Series (Model Range) |
|
Motor Power Range |
37 kW to 250 kW (50 HP to 335 HP) |
37 kW to 250 kW (50 HP to 335 HP) |
|
Working Pressure Options |
7.0 bar / 8.0 bar / 10.0 bar / 13.0 bar |
7.0 bar / 8.0 bar / 10.0 bar / 13.0 bar |
|
Free Air Delivery (FAD) |
6.2 to 43.5 m3/min (at 8 bar reference) |
2.5 to 44.0 m3/min (adjustable output profile) |
|
Specific Power Performance |
Optimized at rated full-load operation |
Optimized across 30% to 100% partial-load profiles |
|
Compression Architecture |
Two-Stage Oil-Injected Screw Airend |
Two-Stage Oil-Injected Screw Airend with VSD Drive |
|
Drive System |
Direct Drive via Flexible Coupling / Gearbox |
Permanent Magnet Motor / Inverter-Driven Direct Drive |
|
Cooling Options |
Air-Cooled or Water-Cooled Configurations |
Air-Cooled or Water-Cooled Configurations |
|
Electrical Supply |
380V / 400V / 415V, 50Hz / 60Hz (Customizable) |
380V / 400V / 415V, 50Hz / 60Hz (Customizable) |
|
Discharge Air Temperature |
Ambient temperature + 8 to 12 degrees Celsius |
Ambient temperature + 8 to 12 degrees Celsius |
|
Residual Oil Content |
Less than 3 ppm (standard oil separation system) |
Less than 3 ppm (standard oil separation system) |
|
Noise Level |
68 to 82 dB(A) depending on motor capacity |
65 to 80 dB(A) with variable fan control |
|
Controller Interface |
Programmable Logic Controller with Digital Display |
Advanced Inverter Touchscreen Controller |
Technical Advantages & Core Engineering Features
Multi-Stage Thermodynamic Optimization
By dividing compression across two distinct stages, the operating temperature range within each airend is minimized. This configuration reduces mechanical stress on bearings and seals, lowers internal pressure differentials, and extends the operational lifespan of core compression components during continuous heavy-duty cycles.
Precision Rotor Profiles and Alignment
The internal rotors utilize high-precision machining tolerances to maintain optimal clearance sealing. This precise engineering minimizes internal air slippage between stages, ensuring consistent volumetric efficiency and stable output performance under varying thermal loads.
Advanced Thermal and Oil Management
Integrated fluid injection and separation systems maintain stable operating temperatures and ensure low oil carryover into the compressed air network. Effective oil-air separation protects downstream equipment and reduces contamination risks in sensitive industrial manufacturing environments.
Modular Structural Design
The internal layout is structured for straightforward access to maintenance points, including oil filters, air filters, separator elements, and coolers. This maintenance-friendly design minimizes downtime during routine servicing and reduces long-term operational upkeep labor.
Typical Industrial Applications
Two-stage rotary screw compressors are widely deployed in centralized utility rooms and heavy-duty production environments:
Metal Processing: Supplying reliable air for machine tools, pneumatic handling equipment, and automated assembly lines.
Automotive Manufacturing: Operating pneumatic actuators, painting systems, and testing equipment across continuous shifts.
Electronics and Battery Production: Delivering high-volume air for automated processes, subject to stringent downstream filtration and drying standards.
Cement and Building Materials: Powering pneumatic conveying systems, instrumentation, and heavy plant utilities.
Textile Manufacturing: Providing stable air supply for spinning, weaving, and high-speed machinery.
Maintenance & Spare Parts Considerations
For industrial plant managers and maintenance teams, lifecycle equipment availability depends heavily on serviceability:
Routine Maintenance Access: Check the layout of oil filters, air filters, oil separators, and fluid drain points for ease of routine servicing.
Airend Reliability: Review design parameters governing bearing life, rotor profile clearances, and thermal management.
Consumables & Spare Parts: Ensure clear schedules for replacing filters, separator elements, and compressor lubricants to avoid unexpected downtime.
Technical Inquiry & Selection Checklist
To receive an accurate technical recommendation and quotation, please provide the following operational parameters:
Required Airflow: Average and peak air demand, number of production shifts, and future expansion plans.
Required Pressure: Compressor discharge pressure and minimum working pressure required at the application points.
Operating Profile: Daily operating hours, annual working days, and whether demand remains stable or fluctuates.
Installation Environment: Ambient temperature, indoor or outdoor placement, ventilation status, and available electrical supply (voltage and frequency).
System Preferences: Air-cooled or water-cooled preference, fixed-speed or variable-speed requirement, and any downstream air treatment specifications.
FAQ
Q: How does a two-stage screw compressor differ from a single-stage model in daily operation?
A: A two-stage model splits the overall compression ratio across two separate airends, reducing the pressure ratio per stage. Under continuous industrial operation and specific working pressures, this thermal design can lower internal leakage losses and improve overall specific power performance compared to a single-stage unit of equivalent capacity.
Q: How do I determine whether my plant needs a fixed-speed or variable-speed two-stage compressor?
A: Evaluate your facility's daily load profile. If your plant operates with a stable, high-volume base load across all shifts, a fixed-speed unit is often cost-effective. If your air demand fluctuates significantly due to shifting production schedules, partial loads, or periodic equipment shutdowns, a variable-speed configuration helps prevent off-load power waste.
Q: What is the impact of ambient temperature and altitude on compressor selection?
A: High ambient temperatures reduce air density and cooling efficiency, while higher altitudes decrease atmospheric pressure and motor cooling capacity. These environmental factors must be factored into the required Free Air Delivery (FAD) and motor sizing calculations to prevent thermal trips or insufficient airflow at the point of use.
Q: What is required when replacing an older compressor in an existing air network?
A: Beyond matching motor power, you must verify actual on-site FAD, existing network pressure, electrical supply compatibility (voltage, frequency, and transformer capacity), room ventilation, and downstream air treatment capacity (such as dryers and air receivers) to ensure balanced system performance.
Hot Tags: two-stage rotary screw air compressor, China two-stage rotary screw air compressor manufacturers, suppliers, factory, automated electric compressor system, heavy duty operation compressor system, high cleanliness air compressor system, high pressure electric air compressor for industrial application, monitoring electric air compressor system, smart electric compressor system