Everyone knows the efficiency brought by the use of CNC milling machining to process workpieces, but there is still a lot to learn about the operation and programming of CNC machining centers. The following is the thread processing method. CNC machining has three methods: thread milling, tap machining and picking machining:

 

 

 

ONE:Thread milling method

 

CNC machining thread milling is the use of thread milling cutters to process large-hole threads and threaded holes of difficult-to-machine materials. Has the following characteristics:
 

1. The cutting tool is generally made of hard alloy material, which has high speed, high CNC machining thread milling precision and high processing efficiency;

 

2. Under the same pitch, whether it is a left-handed thread or a right-handed thread, one tool can be used to reduce the cost of the tool;
 

3. The thread milling method is especially suitable for thread machining of difficult-to-machine materials such as stainless steel and copper. Easy chip removal and cooling, which can ensure machining quality and safety;

 

4. There is no tool front-end guide, it is more convenient to process blind holes with short threaded bottom holes or without undercut holes.
 

 

CNC machining thread milling cutters are divided into two types: machine-clamped cemented carbide blade milling cutters and integral cemented carbide milling cutters. The machine clamp tool can machine holes whose thread depth is less than the length of the blade, and can also machine holes whose thread depth is greater than the length of the blade. Hole; Solid carbide milling cutters are used to machine holes whose thread depth is less than the length of the tool.

 

Note for thread milling CNC programming: so as to avoid tool damage or machining errors.

 

1. After drilling the threaded bottom hole, use the head to process the small hole, then use the boring to process the large hole to ensure the accuracy of the threaded bottom hole;

 

2. The tool generally adopts 1/2 arc trajectory to cut in and out to ensure the thread shape. At this time, the tool radius compensation value should be brought in.

 

TWO :CNC machining milling tap processing method

 

Suitable for threaded holes with small diameter or low hole position accuracy. Generally, the diameter of the threaded bottom hole drill is close to the upper limit of the threaded bottom hole diameter tolerance, which can reduce the machining allowance of the tap and reduce the load of the tap. Improve the service life of the tool.

 

You should choose the right tap according to the material to be machined. Compared with milling cutters and boring cutters, taps are very sensitive to the material being machined. Taps are divided into through holes and blind holes. The front end of the through-hole tap is guided by the length. For the front row chip removal, the machining depth of the thread cannot be guaranteed when machining blind holes. The front end of the blind hole is short, that is, the rear chip, pay attention to the difference between the two; when using a flexible tapping chuck, pay attention to the diameter of the tap shank, the width and square of the tap should be the same as the tapping chuck; the shank of the rigid tapping tap The diameter should be the same as the diameter of the chuck. The programming of tapping processing methods is relatively simple, and they are all fixed modes. Just add the parameter value. Note that the format of the subroutine is different for different CNC systems, and the meaning of the parameter values are also different.

 

Three: pick button machining method

 

Suitable for machining milling large threaded holes on box parts. This method is used when there are no taps and machining thread milling cutters. The thread turning tool is mounted on the boring bar to cut the thread. There are several considerations for implementing click processing methods:

 

1. There must be a delay time for the spindle start to ensure that the spindle reaches the rated speed;

 

2. The sharpening of hand-grinding thread tools cannot be symmetrical, and reverse retraction cannot be used. The spindle should be oriented to move the tool radially, and then back;

 

3. The tool post must be accurate and consistent with the position of the tool slot, otherwise multiple tool holders cannot be used for machining, which will cause confusion and imagination;

 

4. When picking, be careful not to complete the machinig with one cut, so the buckle is very thin, otherwise it will cause a difference with the ground, so it needs to be machined multiple times;

 

5. The buckle machining method is only suitable for single-piece, small batch, special pitch thread processing without corresponding tools, and the machining efficiency is low.

 

The buckle machining method of CNC machining milling is only a temporary emergency method. It is recommended that you use thread processing methods to process tools, which can effectively improve the efficiency and quality of thread machining, reduce processing costs, and improve the efficiency of machining centers.