Laser cutting with compressed air

Laser processing technology has been used globally for industrial cutting purposes.

Since then, advanced, third generation laser technology has led the expansion of cutting processes for a wide range of materials such as sheet metal, wood, plastic, glass, ceramics, textiles, semi conductors and paper. With the recent development of high power, fibre laser cutting machines, processers are able to reduce costs through faster cutting times and reduced gas usage. This greatly improved cutting process has relaced traditional cutting methods particularly in the sheet metal industry.

One of the thermal cutting methods, used in the laser cutting industry is a focused, high power and high-density laser beam to irradiate the workpiece, so that the material at the irradiated place will melt, vaporise or blow away. The main factors affecting the metal laser cutting thickness and cutting efficiency are the power of the laser cutting machine, the type of auxiliary gas, the pressure, and the flow rate of the auxiliary gas.

Laser cutting machines now require high-energy lasers and auxiliary gases to complete the cutting process. The most common auxiliary gases used for laser cutting are oxygen (O2), nitrogen (N2), and compressed air. Compressed air is easier to obtain and cheaper compared to oxygen and nitrogen, making it a common choice for cutting. Air compressors, as the auxiliary gas provider, can play a critical role in laser cutting. The quality of compressed air has a very direct impact on the quality of laser cutting. As all compressed air contains contaminates like moisture and oil, high pressure cleaning of the protective mirror at the laser cutting head is critical to avoid serious consequences to the transmission of the laser beam, disperse the focus, and cause the product to be cut incompletely and produce waste products.

A highly efficient dryer must be utilised to remove excess moisture from the compressed air with high quality filters to remove oil and other contaminants. The dried and filtered compressed air delivered at normal temperature avoids further condensation and ensures the long life, precision and efficiency of the cutting equipment. Using compressed air as a laser cutting gas can greatly reduce your costs to increase profitability.

Cutting gas supply is an essential part of laser cutting but it is also the most expensive utility that you need to supply to your laser cutter. Common cutting gases are nitrogen and oxygen, but the cost of supplying these gases alone can be as high as 90 percent of the total utility cost for the laser.

So is there a cost effective alternative? The answer is yes, depending on the type and the thickness of the material being cut, compressed air can be used as an ideal cutting gas. Compressed air production costs are only one quarter the cost of supplying nitrogen or oxygen which can reduce the utility costs of laser cutting every part down to 25% of other gas applications! Compressed air as the cutting gas can also mean increased cutting speed and throughput. Significant cost savings can be achieved by using compressed air instead of more expensive gases,

With the current need for industrial laser cutting machines operating at 16bar, the supporting air compressor requirement has also increased to 16bar. The higher the pressure, the higher the cutting quality and efficiency. Choosing the right type and model of air compressor is critical to achieve the best cutting results.

New Scroll OXPII-16 integrated air compressor

Specifically designed to deliver high purity, 16bar air power for the laser cutting industry, incorporating advanced technology including permanent magnet drive motor and variable speed control, the Scroll OXP tank mounted air compressor offers a compact, quiet integrated unit for a variety of laser cutting applications. This world class compressor offers lubricated, fixed orbit technology; maximum energy efficiency; it is 100% continuous duty rated; it has a direct drive for zero transmission loss; it has ultra quiet operation; an integrated after cooler, a digital control panel and has low maintenance requirement. kaishan.com.au