Some skills in NC machining
How to prepare NC programming
After determining the processing technology, the following should be understood before programming:
1、 Workpiece clamping method;
2、 Workpiece rough blank size – determine the processing range or whether multiple clamping is required;
3、 Workpiece material: select the tool for processing;
4、 What are the tools in stock? Avoid modifying the program due to the lack of this tool during processing. If you have to use this tool, you can prepare it in advance.
What are the programming principles for safe height setting?
Precision machining
Safety height setting principle: generally higher than the highest height on the island. Or set the programming zero point to the highest plane to avoid the risk of knife collision as much as possible.
Why do tool paths need post-processing?
Since different machine tools can identify different address codes and NC program formats, it is necessary to select the correct post-processing format for the machine tools to ensure that the program can run.
Reasonable selection of cutting parameters
For high efficiency metal cutting, the material to be processed, cutting tools and cutting conditions are the three major elements. They determine the processing time, tool life and machining quality. The economical and effective machining method must be the reasonable choice of cutting conditions.
The three elements of cutting conditions: cutting speed, feed rate and cutting depth directly lead to tool damage. With the increase of cutting speed, the tool tip temperature increases, resulting in mechanical wear, chemical wear and thermal wear. If the cutting speed is shortened by 2%, the tool life will be increased.
The relationship between feed condition and tool wear is very small. However, when the feed rate is large, the cutting temperature increases and the wear is large. It has less effect on cutting tool than on cutting speed. Although the influence of cutting depth on the tool is not as great as the cutting speed and feed speed, when the cutting depth is small, the hardened layer of the material to be cut will also affect the tool life. The user should select the cutting speed according to the processing material, hardness, cutting state, material type, feed rate, cutting depth, etc.
On this basis, the most suitable process conditions were selected. Regular and stable wear is the ideal condition for service life. Don’t want to work at the bottom, want to get rid of the status quo.
But in practice, the choice of tool life is related to tool wear, change of machining size, surface quality, cutting noise, processing heat and other factors. When determining the processing conditions, it is necessary to study according to the actual situation. For difficult to machine materials, such as stainless steel and heat resistant alloy, coolant or rigid blade can be used.
About the author