What is a combined screw air compressor?

Combined compressor is not a specific type of air compressor. The word “combined” means that multiple systems are put together in one setup.

A combined screw air compressor is a self-contained air generation system that compresses air using screw technology and also includes built-in systems for air drying, multi stage filtration and air storage tanks. Everything is placed in one system instead of having all these parts as separate. This makes it super easier to install, use and maintain.

This kind of compressor is heavily used in industries like metal cutting, automotive and fiber laser cutting where clean and dry air at steady pressure is very important for high quality work.

Core concept behind combined screw compressor

A combined screw air compressor is not only a compressor. It’s a complete system that includes:

• One or more screw airends (compression units)
• Air dryers (usually a refrigerated one)
• Multi-stage filtration systems
• Integrated air receiver tanks
• A control system (usually a PLC with touchscreen and sensors)

All of these are installed inside a single setup. There are no external pipes or wires connecting different machines. Everything is already connected and ready to use.

Mechanical and Operational Principles

Normal Screw Systems

A rotary screw air compressor uses two intermeshing helical rotors (male and female) to trap and compress air via positive displacement. As the rotors turn, air is drawn into chambers and pushed toward the discharge port under pressure.

Combined Systems

A standard screw compressor usually has only the compression part. You have to add a dryer, filters and tank yourself which takes space and time.

But in a combined system:

1. Multiple screw airends operate in parallel.
2. Central control adjusts the number of active units based on air demand. This method keeps the pressure steady and saves energy. For example:

• If the air demand is low, only one compressor runs.
• If the demand increases, the second one starts.
• If demand drops again, one unit turns off.

3. Also some systems have variable speed drives (VSD) compressors. This means the motor can slow down or speed up to match how much air is needed.

This combined design gives scalable performance across partial and full-load conditions, also maintaining pressure consistency and flow reliability.

Built-in dryer and filtration system in combined systems

Dryer types used

An air dryer removes water vapor, dust and oil from the compressed air.

1. Refrigerated Dryers

Most combined compressors use a refrigerated dryer.

• Use for cooling to condense moisture.
• Common in general manufacturing.
• Dew point: +3°C to +7°C

2. Desiccant Dryers

• Use hygroscopic material to absorb moisture.
• Suitable for critical applications.
• Dew point: -20°C to -70°C

Filtration stages

After drying, the air passes through multi-stage filtration in combined systems. These filters work together to clean the air:

• Particulate Filter: Removes solid dust and rust.
• Coalescing Filter: Captures oil aerosols and fine moisture droplets.
• Adsorption Filter: Removes hydrocarbon vapors (optional carbon filter).

These filters ensure output air quality meets ISO 8573-1 Class 0 standards:

• ≤0.01 ppm oil
• ≤0.01 μm particles
• ≤ -20°C dew point (with desiccant upgrade)

Integrated air receiver tank

The air receiver tank stores compressed air and acts like a buffer. It balances the air pressure when demand changes. It also gives the dryer and filters time to work properly.

Most tanks are between 400 to 600 liters in size. They also help moisture to settle at the bottom which then gets removed by an automatic drainage system.

They also supply backup air if one compressor is off. Without a tank, the compressor would need to run constantly and struggle to keep the pressure steady.

Use Case for fiber laser cutting

Now let’s look at a real world example of a combined screw air compressor being used in fiber laser cutting. One of the best examples is the DEHAHA 15kW Fiber Laser Cutting Combined Screw Air Compressor.

This air compressor is made for use in fiber laser cutting applications to deliver clean, high pressure and moisture free air. This unit merges high precision compression, drying, and filtration technologies with a storage and drainage system.

Since it has all the important components in one machine, it is easy to install and use. The system is built for high-performance cutting and reliability in industrial settings.

Key functional features

1. High efficiency airend

• Imported rotor assembly
• Optimized for 1.58 MPa discharge pressure
• Provides consistent, high volume airflow and use low energy
• Gives smooth and clean laser cutting results

2. Advanced air purification

High efficiency refrigeration dryer cools air to remove moisture and 5-level precision filtration includes:

• Pre-filter (dust)
• Coalescing filter (oil/water)
• Adsorption filter (vapors)
• Post-filter (particles)
• Sterile-grade filter (optional)

Ensures ISO 8573-1 compliance that is essential for laser optics protection and cut edge cleanliness.

3. 500L integrated air storage tank

• Stores compressed air to stabilize cutting flow
• Supports pressure regulation during peak demand
• Helps maintain cutting accuracy and repeatability

4. Centralized drainage system

• Manages all condensate discharge
• Prevents moisture buildup in pipes and filters
• Keeps the workspace clean and maintenance low

How easy is installation

Installation is quick and easy compared to setting up individual machines.

Steps:

1. Place the unit on a level floor.
2. Connect to the power supply.
3. Connect the air outlet to your air system.
4. Set dew point/alarm values.
5. Start system using control panel.

There’s no need for separate alignment or calibration of parts is required. It’s already built and tested at the factory.

Application areas of this air compressor

This combined screw air compressor is used in different laser cutting applications:

Metal sheet cutting

It helps in cutting metals like steel, aluminum and brass. The clean and dry air gives smooth edges and reduces the chance of oxidation or burns.

Sign making

Sign makers use it to cut letters and shapes from wood, plastic or acrylic. The compressor helps keep cuts sharp and accurate.

Glass engraving

It is also used for engraving designs on glass items like mugs, bottles and window panels. The dry air stops the laser beam from scattering or making errors.

Plastic cutting

The clean air keeps the plastic from burning or melting unevenly. Filters also prevent chemical residue contamination.

Working Conditions and Notes

1. Suitable for environments between -5°C to 45°C
2. Discharge air temperature stays about 10°C to 15°C
3. Runs on 380V / 50Hz. Also custom voltages (460V, 230V, 6KV, 10KV) available
4. Follows ISO1217 and ASME PTC9 testing standards
5. Belt driven mode

Why this unit matches fiber laser cutting needs

Requirement	How DEHAHA 15kW Compressor Meets It
Consistent high pressure	VSD-controlled output at 15.8 bar for stable, clean cut performance
Moisture-free air	Refrigerated dryer keeps dew point low, prevents beam interference
Contaminant-free air	5-stage filtration ensures no oil or particles reach the cutting head
Compact form factor	Single skid layout simplifies setup in CNC/laser rooms
Energy efficiency	VSD reduces energy use during idle or low load cutting sessions
Quiet operation	Noise levels are below 65 dBA, suitable for factory floors

 

 Summary Flow

A combined screw air compressor like the DEHAHA 15kW model is a smart choice for anyone working with fiber laser cutting machines. It includes the core principles of combined rotary screw systems like integrating compression, drying, filtration and storage into one compact unit.

If you want accurate laser cuts, long equipment life and clean results in different materials like metal, plastic and glass, then a combined screw air compressor gives you the performance and simplicity you need for modern production environments.