CNC Knowledge: Several thread treatment methods commonly used in the CNC treatment center!

With the improvement of the performance of the CNC machining center and the improvement of the cutting tool, the method of processing the thread is also continuously and the precision and efficiency of the treatment of the thread gradually increases. In order to allow craftsmen to reasonably select Thread treatment methods in treatment, improve production efficiency and avoid quality accidents, several thread treatment methods commonly used in CNC treatment centers will be summarized as follows:
1. Tiechi treatment method
1.1 Classification and characteristics of TAP treatment
The tap machining hole is the most common treatment method.
In the 1980s, threaded holes used a flexible attack wire, that is to say that the flexible attack cable holder contains the tap. The structure of the flexible attack wire chip is complicated, the cost is high, it is easy to damage and the treatment efficiency is low. In recent years, the performance of the CNC treatment center has gradually improved and the rigid attack function has become the basic configuration of the CNC machining center.
Consequently, rigid attacks have become the main method of treatment of the current thread.
In other words, the tap is held with a rigid spring clip, and the spindle power supply is consistent with the main axis control by the tool machine.
Compared to the flexible attack wire clip, the spring clip is simple, the price is inexpensive and the use is wide. tool. At the same time, rigid attack wires can be used for high speed cut in order to improve the efficiency of using the machining centers and reduce manufacturing costs.1.2 Determination of the background hole
Treatment of the bottom hole of the wire has a great impact on the lifespan of the tap and the quality of the treatment of the wire. Usually, the upper limit of the diameter of the thread bottom forest is close to the tolerance of the tolerance diameter of the thread bottom.

For example, the diameter of the lower hole in the m8 wire hole is 6.7 + 0.27 mm, and the diameter of the drill bit is 6.9 mm. In this way, it can reduce the amount of TAP treatment, reduce the load of the tap and increase the lifespan of the TAP.

1.3 Choice of tap
When choosing a tap, you must first choose the corresponding tap depending on the materials processed.
Because the tap phase is very sensitive to treatment materials for strawberries and knives. For example, the use of the cast iron tap to treat aluminum parts, which can easily lose teeth, fixing and even taps, causing the waste of the room. Second, it must be paid unlike the hole tap and the blind tap. The front of the blind hole is shorter and the crumbs are the rear crumbs. The machining of the blind hole with a tap of the holes cannot guarantee the depth of the treatment of the wire. In addition, if a flexible attack wire clip is used, you should also pay attention to the diameter of the handle of the tap and the width of the square, the same as the attack wire clip; The diameter of the spring clip. In short, only the reasonable choice of TAP can the treatment of smooth treatment.
1.4 CNC programming of TAP treatment
The programming of TAP treatment is relatively simple. Currently, the treatment center is generally solidified by sediments and only the parameters can be allocated. However, it should be noted that the CNC system is different, the sub-program format is different and the meaning of certain parameters is different.For example, the Siemen840c control system, its programming format is: G84 x_y_r2_r3_r4_r5_r6_r8_r8_r9_r10_r13_. Just allocate these 12 parameters during programming.
2.
2.1 Characteristics of thread grinding
Thread grinding is a threaded milling tool.
Thread grinding is mainly used for the treatment of threading holes of the large pore wire and difficult treatment materials. It mainly has the following characteristics:
⑴ Rapid treatment speed, high efficiency and high treatment of treatment. The material to the tool is generally a hard alloy material and the knife is fast. The manufacturing precision of the tool is high, so the grinding screws are high.
具 The grinding of the range of the tool is large. As long as the wire distance is the same, a knife can be used, whether it is a left head or a right rotary wire, which is conducive to reducing the cost of the tool .
(3) Treatment of grinding is easy to exclude and cool. Large components and parts of precious materials.
端 Because there is no guidance before the tool, it is suitable for the blind hole with a shorter threaded background and a hole without a knife groove.
2.2 Classification of the threading strawberry knife
The threaded milling tools can be divided into two types, one is the machine that tightens the hardwriter shredder with hard alloy, and the other is the overall cutting mill in hard alloy. The scope of the clip -type type tool is wide, which can not only treat holes with a length lower than the length of the blade, and can also treat pores with the length of the thread greater than the length of the blade. Global fragmentation of hard alloy is generally used to treat pores with less than the length of the tool.
2.3 CNC programming of crushing threads
The programming of the thread milling tool is different from the programming of other tools. Pay attention to the following points during the preparation:
⑴ First of all, the threaded bottom hole should be well treated and the small diameter holes must be treated with exercises.
When the knife is cut in the cut, the arc trajectory should be used, usually 1/2 lap must be cut or cut. . The compensation value of the radius of the tool must be provided for the moment.
(3) For a week of axis x and y arcs, the main axis must be in the direction of the Z axis in the direction of the Z axis, otherwise it will cause a threaded loop.
： Specific examples: The diameter of the thread fragmentation is φ16, the wire hole is M48 × 1.5 and the depth of the threaded hole is 14.
The treatment program is as follows:
(The thread pore program is slightly slightly, the hole should be cut in the lower hole) G0 G90 G54 X0 Y0 G0 Z10 M3 S1400 M8 G0 Z-4.75 Intersection with the deepest part of the wire G01 G41 x-16 Y0 F2000 Move towards the position of the knife, add compensation for the radius G03 x24 Y0 Z-14 i20 J0 F500 When cutting, use 1/2 lap to cut G03 x24 Y0 Z0 I-24 J0 F400 Cut the entire wire G03 x-16 Y0 Z0.75 I-20 J0 F500 cut out of the G01 G40 x0 Y0 in the center when cutting the arc, cancel the radius compensation G0 Z100 M30
3. Choose the deduction method
3.1 The characteristics of the deduction method
Sometimes large threaded holes can also be encountered on the parts of the box.
Install a threaded knife on the stem of the knife to cut the screw.
The company treated once a lot of parts, the wire was M52x1.5 and the position was 0.1 mm (see Figure 1). The processing requirements were guaranteed by the selection method.
3.2 Precautions for the selection method
After starting the main axis, there should be a delay to ensure that the spindle reaches nominal speed.
When you get back, if you are a screw knife with hand grinding, because the tool cannot be used for symmetry, you cannot use an inversion retraction knife. remote.
(3) The manufacture of the knife rod must be precise, in particular the position of the knife groove must be consistent. If it is incoherent, the multi-two years can be used. Otherwise, it will cause a loop.
Even if it is a very thin loop, you cannot be able to be used when you pick the loop, otherwise it will cause the loss of tooth, the roughness of the surface is bad and at least two knives must be divided.
只 The treatment efficiency is low and only applies to a single piece of small lots, to special thread distance threads and to any corresponding tool.
3.3 Specific examples
N5 G90 G54 G0 X0 Y0 N10 Z15 N15 S100 M3 M8 N20 G04 X5 Distage, so the main axis reaches nominal speed N25 G33 Z-50 K1.5 Picking Orientation of pin N30 M19 N35 G0 X-2 Leave the knife Retirement N40 G0 Z15