In the transformation and upgrading of the manufacturing industry, laser cutting machines are key equipment for achieving "precision manufacturing and flexible production." Compared with traditional plasma cutting, the Ra value of its cut surface roughness has been reduced from 50 μm to below 5 μm, and the material utilization rate has increased from 85% to over 95%. A single high-power device can replace 3 to 4 traditional machine tools and has become a core production tool for processing new energy vehicle battery shells, manufacturing aerospace components, and precision forming of sheet metal.
Technical Core: The optical processing logic of five major systems
Laser cutting machines complete processing through a continuous process of "laser generation – beam transmission – focusing and cutting – waste removal," relying on the coordination of multiple systems such as optics, mechanics, electricity, and numerical control. Its technical principles can be broken down into two major dimensions: core structure and processing technology.
Modern laser cutting machines are composed of five functional modules, and the precision of each module must be controlled at the micrometer level to ensure stable cutting quality.
Laser system: The core power source is classified into three types according to the working medium: fiber laser, CO₂ laser, and solid-state laser. Fiber lasers have high photoelectric conversion efficiency (>30%) and low maintenance costs. The mainstream power ranges from 1000 W to 3000 W. The 30 kW fiber laser of IPG Photonics can cut 10 mm carbon steel at a speed of up to 12 m/min. The CO₂ laser is suitable for non-metallic processing, with a wavelength of 10.6 μm, and the cutting accuracy of acrylic can reach ±0.02 mm. Solid-state lasers mainly focus on precision micro-processing, with pulse widths as low as the femtosecond level.
Beam transmission system: Composed of optical fiber, cable, collimating mirror, and focusing mirror. The transmission loss of optical fiber is ≤0.2 dB/km; the focusing mirror, made of ZnSe material, has a focal length error of ≤±0.1 mm, ensuring that the minimum spot diameter of the laser beam after focusing can reach 0.1 mm. High-end models are equipped with dynamic focusing heads with a response speed of ≤50 μs, which can compensate for material fluctuation errors in real time.
Motion execution system: Includes gantry machine tools, servo motors, and ball screws. The positioning accuracy of the machine tool is ≤±0.02 mm/m, and the repeat positioning accuracy is ≤±0.01 mm. High-end models driven by linear motors have an acceleration of up to 2g and an idle speed exceeding 120 m/min, making them suitable for high-speed, precise cutting requirements.
Auxiliary system: Includes gas supply, cooling, and dust removal devices. Auxiliary gases are classified by process: oxygen (for combustion assistance and accelerated cutting), nitrogen (for oxidation protection), and argon (for inert protection), with adjustable pressure ranges of 0.1–2.0 MPa. The cooling system uses an industrial chiller with a temperature control accuracy of ±0.5℃, ensuring that the working temperature of the laser remains stable at 20–25℃. The dust removal system has a negative pressure of ≥15 kPa and can collect over 95% of cutting smoke and dust.
Core Principles for Safe Operation
Pre-operation preparation: The equipment installation site should have good ventilation, with grounding resistance not exceeding 4 Ω, and a 2-meter safety warning zone should be set up around it. Check that the laser interlock device and protective cover are intact, and confirm that the pressure of the cooling system (normal: 0.2–0.5 MPa) and gas pressure are within range. Operators must wear laser protective glasses (with a protective wavelength matching the laser type).
Operating prohibitions: Do not cut sealed containers or flammable and explosive materials. Never observe the laser beam without protection. Do not open the protective cover of the cutting head while the equipment is operating. Only authorized personnel may operate the equipment.
Special working conditions: When cutting reflective materials (such as aluminum and copper), install anti-reflection films to prevent laser reflection from damaging the laser. When processing thick plates, reduce cutting speed and extend gas purging time. Preheat the cooling system for 15 minutes in advance in low-temperature winter environments (when the oil temperature is below 15℃).
Emergency response: In case of laser failure, immediately cut off the main power supply and contact professional personnel for repair.
Key Points of Maintenance Management
Daily inspection: Check the cutting head lens for contamination (clean immediately with anhydrous ethanol if stains are found), check for gas pipeline leaks, and clean waste residue on the workbench. Check the sealing of the optical fiber connector weekly and calibrate the laser optical path.
Regular maintenance: Replace the cooling system filter element monthly and check the lubricating oil level of the servo motor. Clean the dust inside the laser quarterly and check for laser power attenuation (replace the laser if attenuation exceeds 10%). Calibrate machine tool accuracy annually to ensure the positioning error does not exceed ±0.02 mm.
