How to cut high-quality products with laser cutting machine?
Laser cutting machine for high cutting precision or thickness of parts, must master and solve several key technologies. Focus position control technology is one of them. One of the advantages of laser cutting is that the energy density of the beam is high, so the focal spot diameter is as small as possible in order to produce a narrow kerf. Because the focus lens has a smaller focal depth, the focal spot diameter is smaller, and for high quality cutting, effective depth is also related to the lens diameter and the cut material. It is therefore important to control the focus relative to the position of the surface of the cut material.
How to cut high-quality products with laser cutting machine? Because the laser power density has a great influence on the cutting speed, the choice of lens focal length is an important problem. Laser beam focus After the spot size is proportional to the lens focal length, the light beam through the short focal length lens focus after the spot size is very small, the focus of high power density, is advantageous to the material cutting; but its disadvantage is depth is very short, the adjustment margin is small, the general comparison is suitable for the high-speed cutting thin material.
Since the long focal length lens has a wider focal depth, it is suitable for cutting thick workpieces as long as there is sufficient power density. After determining which focal length lens is used, the relative position of focus and workpiece surface is particularly important to ensure the quality of the cut. Due to the highest power density in the focus, most of the time, the focus position is just on the workpiece surface, or slightly below the surface. During the entire cutting process, it is important to obtain stable cutting quality by ensuring that the focal point is constant relative to the workpiece position.
Sometimes, the lens work due to poor cooling and heat to cause the focal length changes, which need to adjust the focus position in a timely manner. When the focus is in the best position, the cutting seam is the smallest, the most efficient, the best cutting speed for the best cut results. In most applications, the beam focus is adjusted to just under the nozzle. The nozzle and workpiece surface spacing is generally around 1.5mm.
In the process of laser application, there are three kinds of simple methods to determine the focal position, such as focusing and so on:
(1) Printing method: Make the cutting head move from top to bottom, the laser beam is printed on the plastic plate, the minimum print diameter is the focus.
(2) Inclined plate method: with the vertical axis into an angle inclined plastic plate to pull horizontally, looking for the smallest laser beam focus.
(3) Blue Spark Method: Remove the nozzle, blowing air, the pulse laser on the stainless steel plate, so that the cutting head from top to bottom movement, until the blue spark the biggest focus.