CNC Cutting Processing Requirements

CNC cutting processing is a high-precision, high-efficiency machining method that uses computer numerical control technology to control the movement of cutting tools and workpieces, realizing the cutting of various materials. To ensure the quality, efficiency, and safety of CNC cutting processing, there are strict requirements on the processing equipment, cutting tools, materials, process parameters, programming, and operation. These requirements are interrelated and mutually restrictive, and only by meeting all the requirements can the stable and reliable operation of CNC cutting processing be ensured, and high-quality products be produced.

The requirements for CNC cutting processing equipment are the foundation of ensuring processing quality and efficiency. The CNC machine tool used for cutting processing must have high positioning accuracy, repeat positioning accuracy, and motion stability. The positioning accuracy refers to the accuracy of the machine tool's moving parts reaching the specified position, which directly affects the dimensional accuracy of the workpiece; the repeat positioning accuracy refers to the accuracy of the machine tool's moving parts returning to the same position multiple times, which ensures the consistency of batch processing. In addition, the machine tool's spindle speed, feed rate range, and cutting force must meet the processing requirements of different materials and workpieces. For example, high-speed cutting requires the machine tool to have a high spindle speed and a stable feed system; heavy-duty cutting requires the machine tool to have a strong structure and a large cutting force. The CNC system of the machine tool must have powerful functions, stable performance, and easy operation, which can realize complex processing programs and real-time monitoring of the processing process.

Cutting tools are the core components of CNC cutting processing, and their quality and performance directly affect the processing quality, efficiency, and tool life. The requirements for cutting tools include material, geometric parameters, and surface quality. The tool material must have high hardness, wear resistance, heat resistance, and toughness to withstand the high temperature, high pressure, and friction generated during cutting. Common tool materials include high-speed steel, carbide, ceramic, and cubic boron nitride (CBN). Carbide tools are widely used in CNC cutting processing due to their high hardness and wear resistance; ceramic tools and CBN tools are suitable for high-speed cutting and hard cutting of high-hardness materials. The geometric parameters of the tool, such as the rake angle, relief angle, and cutting edge radius, must be designed according to the processed material and processing method. A reasonable rake angle can reduce cutting force and cutting heat; a reasonable relief angle can reduce friction between the tool and the workpiece; a suitable cutting edge radius can improve the strength of the cutting edge and avoid tool damage.

The requirements for processed materials mainly include material composition, mechanical properties, and surface quality. The material composition must be uniform, without impurities, cracks, or other defects, which can avoid uneven deformation or tool damage during cutting. The mechanical properties of the material, such as hardness, tensile strength, and ductility, must be consistent with the processing requirements. For example, materials with high hardness require the use of high-hardness tools and reasonable cutting parameters; materials with good ductility are prone to burrs during cutting, which requires optimizing the tool geometric parameters and cutting speed. The surface quality of the material must be good, without scratches, oxides, or rust, which can avoid affecting the processing accuracy and surface quality of the workpiece. In addition, the material should be pre-treated before processing, such as annealing, quenching, or pickling, to improve its machinability.

Process parameters are crucial to CNC cutting processing, and reasonable setting of process parameters can improve processing efficiency, reduce tool wear, and ensure processing quality. The main process parameters include cutting speed, feed rate, and depth of cut. Cutting speed is the speed of the cutting tool relative to the workpiece, which directly affects the cutting heat and tool wear. Too high cutting speed will generate a lot of cutting heat, leading to tool wear and workpiece deformation; too low cutting speed will reduce processing efficiency. Feed rate is the speed of the tool moving along the feed direction, which affects the surface roughness and processing efficiency of the workpiece. A higher feed rate can improve processing efficiency but may increase surface roughness; a lower feed rate can improve surface quality but reduce efficiency. The depth of cut is the amount of material removed by the tool in one pass, which affects the cutting force and processing accuracy. Too large depth of cut will increase cutting force, leading to machine tool vibration and workpiece deformation; too small depth of cut will require multiple passes, reducing processing efficiency. In addition, the cutting fluid used in CNC cutting processing also needs to meet certain requirements, which can cool the tool and workpiece, lubricate the cutting process, and flush away chips, improving processing quality and tool life.

Programming requirements are another important part of CNC cutting processing. The CNC processing program must be accurate, reasonable, and efficient, which can accurately describe the processing path, processing parameters, and auxiliary operations. The programming personnel must be familiar with the structure and performance of the CNC machine tool, the processing technology, and the programming language (such as G code, M code). The program should be optimized to reduce the processing time and tool wear, such as minimizing the idle travel of the tool, optimizing the processing sequence, and using macro programs for complex parts. In addition, the program must be tested and debugged before formal processing to avoid program errors leading to workpiece scrap or equipment damage. Finally, the operator of CNC cutting processing must have professional skills and operational experience, be familiar with the operation of the machine tool and the processing program, and be able to timely handle various abnormal situations during the processing process, ensuring the safe and stable operation of the processing process.