For processing mold with machining centers, in order to achieve higher efficiency and accuracy requirements and better surface quality, it is necessary to choose from machine tools, shank selection, tool selection, reasonable CNC process plan, program generation, operator requirements, etc. Optimize in all aspects.
High-precision high-speed machining center
High-precision and high-speed processing equipment is the basis for improving the precision and speed of mold processing. The replacement of traditional low-speed machining by high-speed CNC machining centers has become an inevitable trend. With advanced processing equipment, it not only improves the processing speed of the mold, but also reduces the processing steps, shortens the production cycle and the number of clamping times of the mold, and greatly reduces the repair work of the late fitter.
Suitable shank structure
The tool and the shank also play a key role in the quality of the mold. In the rotary tool machining system, the machining performance of the tool can be maximized only by ensuring that the chuck is tightly connected to the machine tool. The taper of the taper shank of the machine tool spindle and the BT shank is 24:7. Under the centrifugal force of high rotation, the taper surface fit gap will increase, so it is not suitable for high speed machining. Generally, when the spindle speed exceeds 16,000 rpm, the HSK hollow shank should be used, and the arbor is over-positioned, which ensures the tight fit between the short cone and end face of the arbor and the machine tool.
Suitable machining tool
Coated carbide tools are becoming more and more widely used, and play an important role in turning, milling, boring, reaming and other processing methods. In order to reduce the tool cost in roughing, it is suitable to use a machine-clamped carbide insert. In semi-finishing, high-speed, high-feed insert tools must be used. In the finishing step, high-precision round-head mirror blades and carbide shanks should be used as much as possible, which not only guarantees machining accuracy, but also costs less than the overall alloy tool.
In addition, it should be noted that the radius of the finishing tool cannot exceed the radius of the inner contour of the part. Select such a tool to circular interpolation or oblique interpolation way for processing, can avoid the use of linear interpolation and over-cutting phenomenon, to ensure the precision machining quality of the mold.
Reasonable CNC process plan
The more high speed and high precision machining, the more important is the rationality of numerical control technology. The processing must be effectively controlled throughout the process. The design of the CNC process scheme can be considered as the state control of the process of a system from the blank filling to the forming.
A good CNC process plan needs to consider a lot of information, such as machine selection, machining method, clamping method, positioning method, tool selection, error and tolerance control, numerical control process, cutting parameters, etc. And must pass the practice summary and the revision unceasingly to carry on the consummation.
Use of CAM software
Whether it is CNC milling programming, turning programming or WEDM programming, good software can provide a rich and practical processing strategy to improve the processing quality and processing efficiency of the mold. For example, the commonly used CIMIAMTRON software can add a spiral function in the roughing of the offset region to make the cutting more stable, eliminate the sudden change of the feed direction between the adjacent cutter paths, and reduce the acceleration and deceleration in the cutting feed, maintain stable cutting load. This software works to extend tool life and protect the machine.
Improve operational skills and responsibility
The operation skills and responsibility of the machining center operators directly affect the quality of CNC machining. They are also the people who know the real-time status of machine tools, tool holders, tools, machining processes, software and cutting parameters. Therefore, improving the operational skills and job responsibility of the machining center operators is also a key factor in improving the quality of CNC machining.
