انواع هلیکال روتاری Helical Rotary

Helical rotary compressors—commonly known as screw compressors—are widely used in medium to large-scale HVAC systems due to their high efficiency, reliability, and continuous operation capability. Unlike reciprocating compressors, helical rotary models offer smoother performance and fewer moving parts, making them ideal for commercial and industrial environments.

Clivet, a leading European HVAC brand, utilizes rotary screw compressors in several high-capacity systems, combining energy performance with smart control technology.

What Is a Helical Rotary Compressor?

A helical rotary compressor uses two helical screws (rotors) to compress refrigerant gas. One rotor (male) drives the other (female), and as the gas moves through the screw channel, its volume reduces—resulting in compression.

Key Process:

Low-pressure gas → enters screw chamber → trapped between rotors → volume reduces → high-pressure gas exits.

Main Types of Helical Rotary Compressors

Oil-Injected Screw Compressors

• How They Work: Oil is injected into the compression chamber to cool, lubricate, and seal the rotors.

• Advantages:

  • High efficiency

  • Longer life due to reduced friction

• Applications:

  • Most HVAC and industrial chillers

  • Medium to large cooling loads

• Clivet Example:

  • Featured in WSAT-XSC and other water-cooled chiller series

Oil-Free Screw Compressors

• How They Work: Rely on high-precision rotor design without oil in the compression chamber.

• Advantages:

  • No risk of oil contamination

  • Ideal for clean environments

• Applications:

  • Hospitals, labs, food/pharma industries

• Disadvantages:

  • Higher cost

  • Requires advanced control

• Clivet Use:

  • Integrated where cleanroom-grade air quality is needed

Single-Screw Compressors

• Design: One main screw rotor meshing with two star-shaped gate rotors.

• Advantages:

  • Balanced forces → less vibration

  • Quieter operation

• Applications:

  • Medium-capacity HVAC systems

• Relevance:

  • Less common but used in some packaged Clivet HVAC units

Twin-Screw Compressors (Double Rotor)

• Design: Two rotors (male & female) directly mesh without valves.

• Advantages:

  • Very efficient for continuous operation

  • Compact design with fewer moving parts

• Applications:

  • Used in Clivet’s modular chillers for commercial buildings

Key Components of a Helical Rotary Compressor

Benefits of Helical Rotary Compressors in HVAC

• Continuous Operation: Ideal for long run-times

• Energy Efficiency: Particularly in variable load conditions

• Quiet Performance: Low vibration levels

• Compact Design: Easier integration in packaged units

• Smart Control: Easily integrated with Clivet’s intelligent BMS

Clivet Applications Using Helical Rotary Compressors

Clivet incorporates screw compressors in:

• Modular chillers for commercial buildings

• Rooftop packaged units with variable-speed screw compressors

• Process cooling systems in industrial facilities

• District cooling plants with integrated control

Examples:
✅ WSAT-XEE
✅ WSAN-XIN
✅ ClivetPack Full DC Inverter Series

Maintenance Tips

• Regular oil checks (for oil-injected models)

• Clean air filters and condenser coils

• Monitor pressure and temperature readings

• Inspect motor bearings for wear

Comparison: Oil-Injected vs. Oil-Free