Comparison of accuracy, speed, effect and stability of laser cutting machine
Cutting accuracy of laser cutting machine
The laser cutting machine has the advantages of high cutting accuracy, fast speed, no limitation of cutting pattern, low processing cost, etc., and it is gradually replacing traditional metal cutting process equipment. At present, the application range of laser cutting machines is becoming wider and wider, and the cutting accuracy of laser cutting machines is related to the processing technology, so it is also one of the most concerned issues for buyers. For the understanding of laser cutting accuracy, many people have certain misunderstandings. In fact, the cutting accuracy of a laser cutting machine does not entirely depend on the equipment itself, but is affected by many factors. Below, let’s briefly understand which factors are most likely to affect the cutting accuracy of the laser cutting machine.
- The spot size after the laser beam passes through the focus. The smaller the spot after the laser beam is concentrated, the higher the cutting accuracy.
- The positioning accuracy of the worktable determines the repeatability of the cutting. The higher the table accuracy, the higher the cutting accuracy.
- The greater the thickness of the workpiece, the lower the accuracy and the larger the slit. Since the laser beam is tapered, the slit is also tapered. The slit is also stainless steel. The slit of 0.3mm stainless steel is much smaller than that of 2mm stainless steel.
- The material of the workpiece has a certain influence on the accuracy of laser cutting. In the same situation, stainless steel has higher cutting accuracy than aluminum, and the cut surface is smoother.
Laser cutting machine cutting speed and cutting effect
Laser cutting has no burrs, wrinkles and high precision. For many electromechanical manufacturing industries, because modern CNC laser cutting systems controlled by computer programs can easily cut workpieces of different shapes and sizes, it is often preferred to punching and molding processes; although the processing speed of laser cutting machines is still slow It is better for die punching, but it has no mold consumption, no need to repair molds, and saves time for mold replacement, thereby saving processing costs and reducing production costs, so it is more cost-effective from an overall consideration. In the metal processing industry where the industrial manufacturing system accounts for a heavy share, many metal materials can be cut without deformation regardless of their hardness. However, for high-reflectivity materials, such as gold, silver, copper, and aluminum alloys, because they are also good heat transfer conductors, laser cutting is difficult, or even impossible.
In the laser cutting process, an auxiliary vapor suitable for the material to be cut is added. When steel is cut, oxygen is used as an auxiliary vapor to produce an exothermic chemical reaction oxidizing material with molten metal, and at the same time, it helps blow away the slag in the slit. Compressed air is used to cut polypropylene and other plastics, and inert vapor is used to cut flammable materials such as cotton and paper. The auxiliary vapor entering the nozzle can also cool the focusing lens, preventing smoke and dust from entering the lens holder to contaminate the lens and cause the lens to overheat. The choice of the cutting speed of the laser cutting machine during cutting is actually very important. The best cutting speed range can be selected according to the equipment description or determined by experiments. Due to the thickness of the material, the difference in the material, the melting point, the thermal conductivity and the melting After the surface tension and other factors, the cutting speed also changes accordingly.
- A moderate increase in the cutting speed can improve the quality of the incision, that is, the incision is slightly narrower, the surface of the incision is smoother, and the deformation can be reduced.
- The cutting speed is too fast, so that the cutting line energy is lower than the required value. The jet in the cutting seam cannot quickly blow off the molten cutting melt immediately and form a large back drag, accompanied by cutting slag and cutting. The surface quality is degraded.
- When the cutting speed is too low, because the cutting site is the anode of the plasma arc, in order to maintain the stability of the arc itself, the anode spot or anode area must find a place to conduct current near the slit closest to the arc, and at the same time it will flow to the jet. More heat is transferred in the radial direction, so that the incision becomes wider. The molten material on both sides of the incision gathers and solidifies at the bottom edge, forming dross that is not easy to clean, and the upper edge of the incision becomes rounded due to excessive heating and melting.
- When the speed is extremely low, the arc may even go out due to the wide cut. It can be seen that good cutting quality and cutting speed are inseparable.
Stability of laser cutting machine
How to measure the stability of a laser cutting machine is a problem that many buyers are more concerned about. The common laser cutting machines on the market are mainly composed of main machine, guide rail, rack and pinion or ball screw, transmission mechanism and other components. Below we will make a simple analysis from these components.
The host is composed of a beam and two longitudinal end frames. The machine gantry is composed of an end frame and a cross beam. The cross beam adopts a rectangular square tube structure, which is tempered to remove internal stress, and has high strength and rigidity. Multiple mobile trolleys can be installed on the cross beam. The horizontal movement device adopts towline. The mechanical part realizes high-precision rack and pinion transmission. The guide rail is made of high-precision special imported guide rails. The precision-processed sliding guide rails are fastened on a concrete or steel frame foundation with a support, and are equipped with adjusting bolts for easy installation and Adjustment. The longitudinal drive system is installed in the longitudinal end frame, and the low-position design makes the transmission more reasonable and stable.
There are two front and rear rolling wheels at the bottom of the longitudinal end frame, which can smoothly roll along the guide rail. The front and rear ends are equipped with guide rail scrapers to ensure that there is no debris on the guide rail surface. Both sides of the bottom are equipped with guiding eccentric clamping wheels. The laser cutting machine ensures the guiding accuracy of the machine is that the machine is equipped with high-strength linear guides (transverse transmission or high-precision precision grinding guides) in the horizontal transmission and torch lifting. The precision-machined gears and racks ensure the vertical and horizontal transmission accuracy of the machine. And eliminate the gap.