CNC flame cutting machines represent the earliest and most established type of CNC blanking equipment. Integrating CNC technology into flame cutting has automated the entire process, significantly improving blanking quality (in terms of dimensional accuracy and cut-edge quality, often eliminating the need for subsequent machining) while boosting production efficiency (through continuous and multi-torch cutting) and material utilization (via nesting). CNC flame cutting machines are typically used for blanking carbon steel plates thicker than 5 mm; cutting plates thinner than this often results in significant deformation and excessive melting at the cut edge.
Cutting quality depends not only on the performance, precision, and reliability of the CNC machine itself but also on gas quality, the quality of the cutting program, and operator proficiency. Common production issues include cutting deformation, surface roughness, and heavy slag or staining. To minimize deformation, one should select appropriate cutting parameters (such as starting points, directions, and sequences), utilize techniques like bridging (interrupted cutting), ensure the support rack is flat and stable, and improve the flatness of the steel plate itself. Ensuring high gas purity (oxygen and acetylene) and stable pressure is fundamental to maximizing efficiency and achieving high-quality cut surfaces. Developed countries often use liquid oxygen; its stable pressure and high purity (exceeding 99.5%) significantly improve cut quality, minimize slag, and allow for faster cutting speeds.
Computer-aided programming and nesting systems are essential companion tools for CNC cutting machines, ensuring rapid, accurate program generation and high material utilization. The computer-aided programming process consists of four main steps: part geometry input, nesting, defining cutting parameters, and post-processing. The quality of the programming software is largely determined by the speed of geometry input and nesting, as these tasks consume the most time in the programming workflow. Key features should include rapid geometry input with easy editing and verification; nesting capabilities that offer both fully automatic multi-level nesting and manual layout options; robust part and production management functions; and the ability to automatically or manually define cutting parameters, including convenient bridging functions.
