Fuselage part:
1) Casting, which is the most important part of computer gongs, directly affects the accuracy, stability, wear resistance and the life of machine tools. After the casting is finished, Dongguan computer gong processing is not immediately used in production. A good casting is that it is subjected to wind and rain, sunlight exposure, natural weathering, and some of them are soaked in sea water. After the casting does not change, the machine tool is not easy to change and can maintain the stability and accuracy of the machine tool for a long time.
2) Spindle, the spindle is used to directly face the workpiece. It is driven by the motor to rotate at a high speed. If the tool holder is installed on the spindle, the workpiece can be cut to meet various production needs. The quality of the spindle will also directly affect the machining accuracy. If the internal bearing is worn, it will easily cause the spindle to swing, and the accuracy of the processed things will naturally have a deviation of several wires 。 At present, the speed of the spindle is generally around 8000 rpm, and the high-speed machine can achieve more than 20000 revolutions. Each machine has only one spindle.
3) The screw rod is also a part of the machine body. It is driven by a servo motor to drive the displacement of the worktable through the copper sleeve of the screw rod to realize the processing needs. If there is a gap in the screw rod, it is also directly reflected in the machining accuracy and finish.
4) There are two kinds of motors: servo motor and frequency conversion motor. Servo motor has good stability, high power of spindle drive motor, and low coordination rate of three-axis drive motor.
5) The coupling is installed between the screw rod and the motor, which is only a linkage action.
6) The lubrication and cooling system is composed of automatic oil pump, spindle oil cooler and chip fluid circulation system. When the machine tool is working, the oil is pumped once a few minutes, and the oil pipe is connected to each corner, such as screw rod, guide rail, etc. if the oil circuit is blocked, it is easy to cause the guide rail wear and affect the accuracy. The main shaft oil cooling is a circulating cooling system added to cool down the main shaft. The spindle with 8000 revolutions may not be required, and the spindle with more than 8000 revolutions must be equipped. The oil in the oil tank is pumped up by the pumping motor in the chip liquid circulation system to flush the workpiece being processed.
7) Sheet metal, sheet metal requirements are not too high, as long as there is no oil leakage, but also involves the appearance of beautiful, image problems.
Whether it is a stamping die or a plastic mold (including injection mold, extrusion mold, blow molding mold, etc.), in order to improve its service life, the parts that constitute the mold cavity are generally made of high-strength wear-resistant materials (such as various brands of alloy structural steel, alloy tool steel and stainless steel, etc.). The hardness of these materials after heat treatment is very high, so it is difficult to use conventional mechanical processing Methods processing. For decades, the best way to deal with this kind of difficult to machine materials is to use special processing.
In China, mold cavity machining is still the “one country” of EDM. EDM (including forming and wire cutting) has been playing a very important role in mold manufacturing.
With the development of production and the speed of product renewal, higher and higher requirements are put forward for the production efficiency and manufacturing quality of mould, so the problems existing in EDM are gradually exposed. From the physical essence, Dongguan precision computer gongs machining EDM is a kind of “micro cutting” process relying on discharge ablation, the processing process is very slow; in the process of partial high temperature discharge ablation of the workpiece surface by EDM, the physical mechanical properties of the workpiece surface will be damaged to a certain extent, and micro cracks and surface roughness will often occur on the surface of the cavity It can not meet the requirements of the mold, so the cavity parts after electrical machining generally have to be ground and polished manually. Therefore, the production efficiency of EDM is very low and the manufacturing quality is unstable. In many occasions, mold has become a key factor affecting the development speed of new products.
Since the 1990s, high speed machining (HSC) has been gradually applied in the mold industry abroad, and good results have been achieved. Compared with EDM, the main advantages of high speed machining are as follows
Good product quality: high speed cutting can process parts at a cutting speed about 10 times higher than the conventional cutting speed, The blank material is cut off from the workpiece in an instant before it is fully deformed, and the residual stress on the surface of the workpiece is very small; most of the heat generated in the cutting process (more than 95) is quickly taken away by the chips, and the thermal deformation of the workpiece is small; in the high-speed machining process, the main shaft of the machine tool operates at a very high speed (10000-80000r / min), and the excitation frequency is far away from “machine tool” The natural frequency range of the “tool workpiece” system makes the machining process of the parts stable without impact. Therefore, the machining precision of the parts is high, the surface quality is good, and the roughness can reach ra0.6 μ M. After high-speed milling cavity, the surface quality of Dongguan high-speed computer gong machining can reach the grinding level, so many subsequent finishing processes can be omitted.
High production efficiency: using high-speed machining center or high-speed milling machine to process mold can complete rough and finish machining of cavity and other parts of mold parts in one clamping of workpiece, which is called “one pass machining”. The cutting speed is very high, and the efficiency of machining process itself is several times higher than that of electrical machining. except
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