Jul 10
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Laser Cutting Machine Fundamentals
To understand laser cutting machine fundamentals one must first realize that there are 3 unique configurations of laser cutting machine: Moving material, Flying Optics and Hybrid machines. These are defined by the way the laser is moved over the material. Just like on a graph the axes of motion are named the X axis and Y axis. If the cutting head can be adjusted it is usually designated the Z axis.
The main characteristic of flying-optic laser cutters is the fixed work surface which has several advantages. The laser moves over the material in both directions. This means that flying optic cutters can hold the material still during cutting, and sometimes don’t require the material to be fixed. The moving mass is constant, so dynamics aren’t affected by the changing size and weight of the material, as would be the case with a moving material laser. These types of laser cutter are the faster of all three types and have faster acceleration and top speeds than other systems.
Moving material lasers have a laser and mobile table below it for moving the material under it. This provides a constant distance between the laser and the work piece and a central point from which cutting slag or ejecta can be removed. The advantage with these machines is that they requires fewer optics. The disadvantage is that the weight of the material that can be cut is fixed by the table’s ability to safely move it into position. As a result of the machine having to be constantly loaded and unloaded piece by piece and because of their weight limitations machines are usually regarded to be the slowest.
Hybrid laser cutters combine flying head and stationary head laser cutters. The table runs on one axis and the cutting head on another. The advantage hybrid machines have over flying optics laser cutters is that they deliver a more sustained beam delivery path and also a less complicated beam delivery method. Because of this, hybrid laser cutting machines are also more energy efficient.
Pulsed lasers are perfect for piercing jobs, such as cutting holes. They also offer advantages when it comes to working with lightweight materials because they don’t provide a steady beam which may overheat and ultimately melt the material. Most industrial laser cutter have the ability to pulse or cut using a continuous beam – ordinarily called CW cutting.
To improve hole quality double pulse lasers can also used. These are a series of pulse pairs that can be used to increase the material removal rate. This method is very straight forward; the first pulse cuts a hole in the surface of the work piece and the other prevents the ejecta or “slag” from adhering to the area around the hole or cut. Once again, the advantage is a cleaner material surface.
The outstanding quality of materials cut by laser far exceeds those that have been cut by conventional means. This is because the beam leaves a clean, finished surface. The use of any type of laser cutter facilitates more accurately cut material within a shorter time than through ordinary methods.
Marc Anderes is the VP of Operations of Maloya Laser which specializes in Metal Manufacturing and <A href=”http://www.MaloyaLaser.com”>Laser Cutting</a> with state-of-the-art <A href=”http://www.maloyalaser.com/capabilities_equipment.php”>laser technologies</a>, for machinery, aerospace, medical, scientific and transportation requirements.