How To Protect The Engraving Machine Tool During Processing?

11. What is the tool life formula?

Tool life is mainly the tool life in the processing of steel materials. The empirical formula is: (T is the tool life, CT is the life parameter, VC is the cutting linear speed, f is the amount of knife per revolution, and P is the depth of the knife). Among them, the cutting linear speed is the biggest influence on tool life. In addition, tool radial runout, tool grinding quality, tool material and coating, and coolant will also affect tool durability.

12. How to protect the engraving machine tool during processing?

1) Protect the tool setter from excessive oil erosion.

2) Pay attention to the control of flying chips. Flying chips are very harmful to the machine tool. Flying into the electric control cabinet will cause a short circuit. Flying into the guide rail will reduce the life of the lead screw and the guide rail. Therefore, the machine tool must be The main part of the seal is well sealed.

3) When moving the lamp, do not pull the lamp cap, it is easy to damage the lamp cap.

4) During the machining process, do not observe near the cutting area to avoid flying chips to injure your eyes. When the spindle motor is rotating, it is forbidden to perform any operations on the work surface.

5) When opening and closing the door of the machine tool, do not open and close the door violently. During the finishing process, the impact and vibration during the door opening process will cause the machined surface to have knife marks.

6) The spindle speed must be set, and then start processing. Otherwise, because the spindle starts to rotate slowly, it will start processing without reaching the desired speed and the motor will be suffocated.

7) It is forbidden to place any tools or workpieces on the beam of the machine tool.

8) It is strictly forbidden to place magnetic tools such as magnetic suction cups and dial indicator holders on the electric control cabinet, otherwise the display will be damaged.

13. There is a phenomenon of holding back during the processing of a new tool, and the processing is very laborious. What parameters need to be adjusted at this time?

The reason why the machining is very laborious is that the power and torque of the spindle cannot withstand the current cutting amount. A reasonable approach is to remake the path to reduce the depth of the tool, the depth of the groove, and the amount of trimming. If the overall processing time is less than 30 minutes, you can also adjust the cutting speed to improve the cutting state.

14. What is the role of cutting fluid?

Pay attention to cooling oil for metal processing. The role of the cooling system is to take away the cutting heat and flying chips, and play a role in lubricating the processing. The coolant will remove the cutting heat, reduce the heat transferred to the tool and the motor, and increase their service life. Take away flying chips to avoid secondary cutting. Lubrication can reduce the cutting force and make the processing more stable. In the copper processing, the selection of oil-based cutting fluid can improve the surface quality.

15. What are the stages of tool wear?

Tool wear is divided into three stages: initial wear, normal wear, and sharp wear. In the initial wear stage, the main reason for tool wear is that the temperature of the tool is low, and the optimal cutting temperature is not reached. At this time, the wear of the tool is mainly abrasive wear. Such wear has a greater impact on the tool. More knowledge of CNC programming Pay attention to the WeChat public account (CNC programming teaching) to receive the tutorial, it is easy to cause the tool to collapse. This stage is a very dangerous stage. If it is not handled well, it may directly cause the tool to collapse and fail. When the tool passes the initial wear period, the cutting temperature of the tool reaches a certain value. This is the main wear is diffusion wear, and its function is mainly to cause local spalling. Therefore, the wear is smaller and slower. When the wear reaches a certain level, the tool fails and enters a period of rapid wear.

16. Why do tools need to be run-in and how to run-in?

We mentioned above that the tool is easy to collapse in the initial wear stage. In order to avoid the phenomenon of tool collapse, we must run-in the tool. The cutting temperature of the tool is gradually increased to a reasonable temperature. It is verified by experiments that the same processing parameters are used for comparison. It can be seen that after running-in, the tool life has increased by more than 2 times.

The method of running-in is to reduce the feed rate by half while maintaining a reasonable spindle speed, and the processing time is about 5-10 minutes. Take a small value when processing soft materials, and take a large value when processing hard metals.

17. How to judge the severe wear of the tool?

The method to judge the severe wear of the tool is:

1) When listening to the processed sound, there is a harsh call;

2) Listening to the sound of the main shaft, the main shaft is obviously holding back;

3) It feels that the vibration increases during processing, and the machine tool spindle appears obvious vibration;

4) Looking at the processing effect, the knives on the processed bottom surface are sometimes good and sometimes bad (if this is the case at the beginning, it means that the depth of the knife is too deep).

18. When should I change the tool?

We should change the tool at about 2/3 of the tool life limit. For example, the tool is severely worn in 60 minutes, and the next time the tool is processed, the tool should be changed within 40 minutes, and the habit of changing the tool regularly should be developed.

19. Can severely worn tools continue to be processed?

After the tool is severely worn, the cutting force can be increased to 3 times the normal. The cutting force has a great influence on the service life of the spindle electrode. The service life of the spindle motor and the force are inversely proportional to the third power. For example, when the cutting force is increased by 3 times, processing for 10 minutes is equivalent to using the spindle for 10*33=270 minutes under normal conditions.

20. How to determine the protruding length of the tool during roughing?

The protruding length of the tool is as short as possible. However, in actual processing, if it is too short, the length of the tool must be adjusted frequently, which will affect the processing efficiency too much. New technicians often have this kind of problem in our factory Guandiao cnc. We have practiced it for a long time and finally solved it perfectly. So how should we control the extension length of the tool in actual processing? The principle is as follows: a φ3 diameter cutter bar can be processed normally if it protrudes 5mm. The φ4 diameter tool bar can be processed normally if it protrudes 7mm. The φ6 diameter tool bar can be processed normally if it protrudes 10mm. Try to go below these values when loading the knife. If the length of the upper knife is greater than the above value, try to control the depth of the machining when the tool is worn. This is a bit difficult to grasp and requires more exercise.

21. What should I do if the tool breaks suddenly during processing?

1) Stop processing and check the current serial number of processing.

2) Check whether there is a broken knife body at the broken knife, and take it out if there is one.

3) Analyze the reasons for tool breakage. This is the most important thing. Why is the tool broken? If we want to analyze, we must analyze the various factors that affect the processing mentioned above. But the reason for the broken tool is that the force on the tool suddenly increases. Or the path problem, or the tool jitter is too large, or the material has lumps, or the spindle motor speed is incorrect.

4) After the analysis, change the tool for processing. If the path is not changed, the original serial number should be advanced one serial number for processing. At this time, you must pay attention to lower the feed rate. One is because the broken tool is hardened severely, and the other is the tool running-in.

22. How to adjust the processing parameters when roughing is not good?

If the tool life cannot be guaranteed at a reasonable spindle speed, when adjusting the parameters, adjust the cutting depth first, then adjust the feed speed, and then adjust the lateral feed again. (Note: There is also a limit to adjusting the depth of the knife. If the depth of the knife is too small and there are too many layers, although the theoretical cutting efficiency is high, the actual processing efficiency is affected by other factors, resulting in the processing efficiency being too low. At this time, you should change to a smaller tool for processing, but the processing efficiency is higher. Generally speaking, the minimum cutting depth cannot be less than 0.1mm.