How To Choose Best Air Compressor For Laser Cutting Machine?

Many customers wonder why an air compressor is needed for a laser cutting machine and how to select the best one. This article aims to provide guidance.

Working Principle of a Laser Cutting Machine

Laser cutting machines rely on a pressurized gas source to operate effectively. Common auxiliary gases include oxygen, nitrogen, compressed air, and sometimes argon. Depending on the gas pressure, these can be classified as either high-pressure or low-pressure gases.

As the demand for cutting thicker plates and improving efficiency has grown, the required compressed air pressure has increased. Where it was once common to use 1.25MPa to 1.3MPa, today higher pressures of 2.0MPa to 3.0MPa are sometimes required. The most widely used compressed gas pressure in the market is around 1.6MPa.

Why Is an Air Compressor Needed for Laser Cutting?

An air compressor is essential for laser cutting because it provides clean, dry, and stable air, which improves cutting quality and results. The compressed air helps in several key ways:

- Power Supply: It stabilizes the workbench by providing the necessary pressure to maintain smooth operation.

- Cleaning and Purging: The air compressor purges and cleans the optical system, removing debris and preventing the buildup of moisture, dust, and impurities that could affect cutting accuracy.

- Lens Protection: It prevents contamination of the laser machine's lenses by oil stains or other pollutants.

For laser cutting, the air compressor must deliver high-quality compressed air that is free of oil and moisture to ensure optimal performance and longevity of the equipment.

Importance of Air Assist in Laser Cutting

Air assist is crucial for laser cutting and engraving as it enhances both the quality of the results and the safety of the machine and operator.

- Improved Cutting and Engraving Quality: Air assist removes debris and fumes generated during cutting or engraving, preventing them from obstructing the laser beam. This leads to cleaner cuts, reduced charring, and finer engraving details.

- Cooling and Protection: The air assist pump cools the material being worked on and the laser lens, reducing the risk of thermal damage and helping to extend the lifespan of the equipment.

Incorporating air assist into your laser cutter setup is essential for achieving optimal performance, maintaining safety, and prolonging the life of the machine.

Types of Air Compressors for Fiber Laser Cutting Machines

1. Integrated Air Compressor (Screw Air Compressor):  

This type integrates key components—such as the air compressor, refrigeration dryer, cylinder, and gas storage tank—into a single frame, offering a compact and efficient solution.

2. Split Air Compressor:  

In this setup, the compressor main unit and the gas storage tank are separated and connected via pipelines to create a complete compressor system, allowing for more flexible installation options depending on space and requirements.

Integrated vs. Split Laser Air Compressor

1. Structure  

- Integrated Air Compressor: Features a compact structure and small size, ideal for spaces with limited room.

- Split Air Compressor: Larger in size, requiring dedicated space for installation and storage.

2. Use Cases  

- Integrated Air Compressor: Best suited for small spaces such as maintenance workshops and car repair stations. Its compact design and ease of maintenance make it popular in industries where space is limited.

- Split Air Compressor: Designed for industries requiring high voltage stability and continuous use, such as chemical plants and electronics manufacturing. The gas tank capacity can be customized based on need.

3. Moisture Removal  

- Integrated Air Compressor: Has weaker moisture removal capabilities, so regular drainage is necessary to maintain proper function.

- Split Air Compressor: Equipped with more advanced moisture removal systems, offering stronger water removal performance.

4. Maintenance  

- Integrated Air Compressor: Easier and more flexible to maintain due to its compact structure, though its numerous connecting parts can make maintenance more complex.

- Split Air Compressor: More stable and fixed, though harder to maintain, it is better suited for handling large-capacity gas compression.

What Kind of Air-Assisted Compressor Do You Need for Laser Cutting?

CO2 Laser Cutting Machine:

The power of CO2 laser cutting machines typically ranges from 100W to 1500W, and the choice of air compressor should match the production needs:

- For 100W–200W CO2 laser cutting machines, a 1.5-horsepower air compressor is sufficient.

- For 200W–400W machines, a 2.2–3.0 horsepower air compressor is recommended.

- For 400W–600W machines, a 3.0–5.5 horsepower air compressor is needed.

- For machines with more than 600W, an air compressor with 7.5–10 horsepower or higher is required.

Fiber Laser Cutting Machine:

The power of fiber laser cutting machines usually ranges between 300W and 6000W. Here’s how to choose an air compressor:

- 300W-800W fiber laser cutting machine is suitable for 2.2-3 horsepower air compressor;

- 800W-1500W fiber laser cutting machine requires an air compressor with a power of more than 5.5 horsepower;

- 1500W-6000W fiber laser cutting machine requires an air compressor with more than 10 horsepower.

When selecting an air compressor, it’s crucial to ensure that it provides sufficient air pressure and gas production. Additionally, quality and reliability are key factors to consider for optimal machine performance.

How to Choose the Best Air Compressor for Laser Cutting

1. Exhaust Volume:

The air compressor for laser cutting must deliver stable air pressure to maintain consistent cutting quality and efficiency. Choosing the correct air compressor involves matching its pressure output with the specific requirements of the laser cutting process. Inconsistent air pressure can lead to poor cutting results and lower productivity.

It's also crucial to consider the compressor’s exhaust volume and flow rate. The compressor should meet the high-flow gas output needed for laser cutting, but avoid selecting one with an excessively large exhaust volume. If the exhaust volume far exceeds the demand, even with frequency conversion, it can lead to over-supply. This may cause the compressor to frequently cycle between starting and stopping, which can result in emulsification of the lubricating oil and shorten the compressor's lifespan.

2. Pressure:

Adequate pressure is essential, but it must be balanced with the laser's power. High pressure alone won’t improve cutting if the laser power isn’t sufficient. The laser must be powerful enough to efficiently melt and cut through materials.

3. Compressed Air Quality:

The quality of compressed air directly affects the cutting performance. Laser cutting requires high-purity gas, and contaminants like water mist and oil can severely impact the process. If unclean air is sprayed at high pressure onto the protective mirror of the laser cutting head, it can obstruct the laser beam, disperse focus, and result in poor cuts or wasted materials.

Specialized air compressors for laser cutting are often equipped with micro-oil twin-screw technology and post-processing systems, forming what is known as a "four-in-one" air compressor system. These systems ensure the delivery of clean, high-quality compressed air, essential for maintaining cutting precision and machine longevity.

Take carbon steel as an example of the criteria for selecting an air compressor for laser cutting:

Reliable Performance and Stability

The air compressor needs to have reliable performance and stability to ensure the continuity and stability of air pressure output during the cutting process, and to avoid reduction in cutting quality and efficiency caused by air compressor failure.