The flat bevel fiber laser cutting machine has become a core processing equipment in fields such as steel structures and pressure vessels due to its high-precision and highly flexible bevel cutting capabilities. It breaks through the limitations of traditional cutting equipment that requires multi process coordination for groove processing, and achieves single step groove cutting of flat sheet metal through precise coordination of laser energy and mechanical motion. Thoroughly analyzing its cutting principle is of great significance for optimizing process parameters and improving processing quality.
Laser generation and energy conduction are the fundamental steps in cutting. The core of the system is a fiber laser, which generates continuous or pulsed laser by exciting the gain medium through a pump source. After being amplified by resonant cavity oscillation, it forms a high-energy density laser beam. Unlike traditional CO ₂ lasers, fiber lasers have shorter wavelengths, stronger energy concentration, and can achieve flexible guidance of laser beams through fiber transmission, reducing energy loss during transmission. After the laser beam is transmitted to the cutting head through an optical fiber, it is focused into a micrometer sized spot by a focusing lens group, which sharply increases the energy density at the spot and provides an energy basis for the instantaneous melting or gasification of the material.
The synergistic control of material thermal action and cutting process is the core principle. When the focused laser spot acts on the surface of the sheet, the material is instantly heated to the melting or gasification temperature. At this time, the auxiliary gas system synchronously sprays high-pressure gas - nitrogen, oxygen, etc. are often used when cutting metal materials. Oxygen can react with the metal to release heat to assist cutting, while nitrogen is used to prevent oxidation of the cut. High pressure gas simultaneously blows away the molten material from the cut, forming an initial cut. Unlike ordinary flat cutting, groove cutting requires adjusting the angle between the laser beam and the surface of the sheet through the swing mechanism of the cutting head. The swing mechanism is precisely driven by a servo motor, which can achieve continuous cutting of grooves at different angles, meeting the requirements of various groove forms such as V, U, Y, etc.
The linkage between the numerical control system and the motion mechanism ensures the accuracy of the groove. After importing the groove processing drawing of the workpiece into the CNC system, the cutting trajectory and the motion program of the swing mechanism are automatically generated. By controlling the plane motion of the X and Y axes and the swing motion of the cutting head in real time, the laser spot always moves along the preset groove contour. At the same time, the system monitors the matching of cutting speed, laser power, and auxiliary gas pressure in real time, dynamically adjusts parameters according to the thickness and material of the sheet, and avoids groove angle deviation or incision slag hanging caused by parameter imbalance.
In summary, the cutting principle of the flat groove fiber laser cutting machine is an organic unity of "laser energy focusing material thermal removal angle mechanism groove forming CNC linkage control accuracy". Its core advantages stem from the high energy density of fiber lasers and the flexible adjustment of cutting head angle mechanisms. With the upgrading of CNC technology, this equipment will achieve higher precision groove processing, promoting the upgrading of equipment manufacturing processes.