Machining center programming knowledge
Due to the different numerical control system of the CNC milling machine configuration, the instructions used have certain differences in definition and function, but the basic functions and programming methods are the same.
The main function of CNC milling machine
Point Control Function The position control of CNC milling machine is mainly used for hole machining of workpieces, such as center drilling positioning, drilling, reaming, boring, reaming and boring.
The continuous control function mills the plane and surface of the workpiece by linear interpolation, circular interpolation or complex curve interpolation movement of the CNC milling machine.
Tool radius compensation
If you program directly according to the workpiece contour, the actual contour will have a larger tool radius value when machining the inner contour of the workpiece; the actual contour will be smaller than the tool radius value when machining the outer contour of the workpiece. Using the tool radius compensation method, the CNC system automatically calculates the tool center trajectory so that the tool center deviates from the workpiece contour by a tool radius value, thereby machining the contour that meets the drawing requirements. By using the tool radius compensation function, the tool radius compensation amount can be changed, and the tool wear amount and machining error can be compensated for rough machining and finishing of the workpiece.
The tool length compensation function changes the compensation amount of the tool length, which can compensate the length deviation value after the tool change, and can also change the plane position of the cutting process and control the axial positioning accuracy of the tool.
The fixed cycle machining function applies fixed cycle machining instructions, which simplifies the machining program and reduces the amount of programming work.
Subprogram function If the workpiece shape is the same or similar, it is written as a subroutine and called by the main program, which simplifies the program structure. The function of the reference subroutine makes the machining program modular, and is divided into several modules according to the process of the machining process, which are respectively written into subroutines, which are called by the main program to complete the machining of the workpiece. This modular program facilitates machining and optimization and optimizes the machining process.
CNC milling machine processing range
Planar machining: CNC machine milling planes can be divided into horizontal (XY) machining of workpieces, positive plane (XZ) machining of workpieces and side plane (YZ) machining of workpieces. This planar milling can be done using a two-axis, semi-controlled CNC milling machine.
Surface Machining: If milling a complex surface, you need a CNC milling machine with three or more axes.
CNC milling machine equipment
Common fixtures for fixture CNC milling machines mainly include flat jaws, magnetic chucks and platen devices. For workpieces with large in-process, large-volume or complex shapes, it is necessary to design a combination fixture. If pneumatic and hydraulic clamps are used, the workpiece can be automatically mounted by program control fixtures, which can further improve work efficiency and reduce labor intensity.
Commonly used milling cutters include end mills, face milling cutters, forming cutters and hole machining tools.