Understanding High-Pressure Air Cutting

Assist gases play a critical role in laser cutting. They can cool the work area, prevent oxidation, and even remove molten material. However, new technology allows assist gases to become effective, affordable machining solutions. Advanced clean dry air solutions can now keep up with high-performance laser cutters. If you are looking for faster throughput and alternative laser-cutting solutions, high-pressure air cutting can help.

What Is High-Pressure Air Cutting?

High-pressure air cutting uses compressed air as the assist gas in laser cutting. Traditional shop air equipment has a lower pounds per square inch (psi). High-pressure equipment delivers air at 400 to 500 psi. It delivers the velocity, cooling, and gas purity needed to maintain clean edges and intensive feed rates, even at scale. 

Nitrogen and oxygen are the traditional assist gases in machining. Nitrogen is preferred for its oxidation-preventing properties, but it is more expensive to obtain. Atmospheric air is 78% nitrogen and 21% oxygen. With the right tools, compressed air can mimic the properties of these assist gases while avoiding the higher costs.

Previous air-cutting technology was insufficient for high-volume applications. Today, advanced systems can achieve fast, superior-quality cuts with only high-pressure air. Your operation can avoid supply challenges and increasing supply costs while maintaining production.

How High-Pressure Air Cutting Works

Air-assisted laser cutting systems provide dry, compressed air during the machining process. They remove molten material, cool the area down, and maintain a clean kerf line. Laser sectioning slices through metals and other materials. This process can create extremely high temperatures and molten metal. Without an assist gas, the metal will melt back into the kerf line — the spaced cuts. Compressed air can prevent these issues effectively without the increased cost and more difficult sourcing of pure nitrogen or oxygen.

Laser systems need more than off-the-shelf compressors to use air effectively. A proper high-pressure air cutting setup requires:

• High-capacity air dryers.
• Multi-stage filtration equipment.
• Pressurized air tanks. 

Any moisture, particulates, or pressure loss during production can lead to production errors. Excess moisture affects cut quality and optics, and particulates and oils contaminate the material and the cut area. Pressure loss means a less effective air stream.

A well-made air cutting solution will deliver filtered and dried air into assist gas lines. The nozzle directs high-pressure streams into the cut path, creating a clean, sharp edge with less dross and reduced post-processing.

Why Use Air-Assist Laser Cutting?

High-pressure air machining can deliver performance similar to nitrogen at a lower cost. Investing in a high-performance dry air system offers your business:

1. Savings

Compressed air is far more affordable and available than bottled nitrogen. Since air is all around us, it is easier to obtain, compress, filter, and dry on-site. The system pulls in air from around it — no bulk gas deliveries or expenses. On-site air or nitrogen generation systems eliminate these challenges. Facilities that switch to clean dry high-performance air systems can save on consumables and logistics. Reduce the cut cost without sacrificing quality.

2. Minimal Maintenance

Air assist systems offer lower maintenance and downtime than managing regular gas deliveries or bulk nitrogen tanks. There is no pausing for gas restocking. No tank swaps and fewer supply concerns mean more uptime and reduced maintenance costs. Your operators get greater scheduling flexibility for other system needs.

3. Fast and Clean Results

High-pressure air delivers excellent speeds, even if you are in high-volume production. While nitrogen leads in some edge finish applications like thicker stainless steel, compressed air is close behind. When tested on mild steel, high-performance air had a speed of 800 inches per minute (IPM) compared to nitrogen’s 900 IPM. Get comparable speeds with minimal post-processing and reduced emissions.

4. Modern Integration

Today’s fiber laser systems are built for speed and precision. Air assist solutions deliver the psi needed to work on aluminum, mild steel, and stainless steel. Get clean dry air that delivers superior results to refrigerated air while providing the power, results, and cost control your business needs.

Air-Assisted Laser Cutting Limitations

High-pressure air cutting offers major advantages to your operation. However, some limitations need consideration:

• Edge quality: When used properly, high-pressure dry air provides clean, sharp edges. However, it requires the right support system. Poor filtration, air dryness, and nozzle size can create inconsistent results. Make sure you choose a quality system designed to meet your needs.
• Material limitations: Air cutting is ideal on mild steel and aluminum. However, it might not perform as well on oxidation-sensitive materials. Air’s oxygen content can lead to discoloration or increased edge roughness in some components. Make sure you are using nitrogen for sensitive parts or materials that need corrosion resistance.
• Initial requirements: High-pressure air systems need specialized compressors, filtration, and air dryers. These solutions can increase upfront investment costs compared to basic shop air setups. However, long-term savings on gas delivery and downtime can offset these costs.

Considerations for High-Pressure Air Cutting

If you are considering an air-assist system for your laser cutting, ensure the assist gas works with your application. Laser performance, reliability, and cost depend on having the right system for the job.

Material

Air is an excellent assist gas choice for mild steel, stainless steel, and aluminum. Air systems effectively treat materials that are resistant to oxidation or are thinner. Due to oxygen in the air, thicker stainless steel may oxidize and see a reduced edge finish. Always match your assist gas to the material composition and application requirements.

Cutting Speed

High-pressure air performs well at elevated speeds, particularly on thin to medium-thickness sheets. The higher the operational speed, the higher the compressed force needed to maintain cut quality. Double-check the system’s setup to ensure efficient throughput.

Cutting Quality

Air can deliver high-quality edges, but the cut consistency depends on clean, dry air and precise nozzle alignment. Poor filtration or moisture leads to spatter and rough edges. Tight tolerance or decorative applications require testing to validate cut quality before production begins.

Choosing the Right Assist Gas Partner

High-performance air cutting in laser cutting is a highly specific area. Your facility needs equipment that works with your materials and delivers the right results without driving up costs and slowing down production. Investing in just any system could lead to poor results or excessive ongoing repair expenses.

Choose an experienced partner who understands the industry. They should be able to help you achieve measurable gains on the shop floor. Look for:

• Industry credentials: Reliable partners will work with leading manufacturers and have years of experience in the industry. You want partners with access to the latest industry technology, insights, and integration capabilities.
• Expert quality control: Systems and operations should be backed by industry standards for quality control. The right partner will deliver solutions tailored to your needs and confirm the system works as intended.
• Dedicated service: Basic service is not enough in laser cutting. Look for partners that offer ongoing support from trained technicians. Your team should be able to run the system with confidence.

Upgrade Your Cutting Results With Liberty Systems

When it comes to compressed air or nitrogen systems, the right technology can make all the difference. You need a partner who can understand and achieve your goals. At Liberty Systems, our focus is on solving real problems and supporting customers beyond the sale.

Whether you need a complete nitrogen solution, a high-pressure air system tailored to your shop, or expert support for existing equipment, we can help. Our in-house-trained technicians and ISO 9001:2015 certified QMS process ensure you get long-term reliability. Contact us today to see how we can transform your production results.