First of all, you need to ensure the stability of the lathe, that is, the fixation of the lathe, that is, whether the spindle will vibrate at high speed, and that the coolant is very important, Secondly, your cutting tool should be well ground, and the chip removal groove should be well opened to prevent the workpiece from being scratched due to poor chip removal, and the turning tool should be made into an arc angle when chamfering. In addition, the tool should not be resistant when loading.
Generally speaking, the more precise ones must go through the following steps: blanking, roughing, fine grinding, finishing and surface treatment.
- Cutting. Generally, the work of cutting is handed over to the apprentice or the special staff, so the requirements of cutting are not high. Generally, 3-5mm allowance will be left for roughing. When laying down materials, too much allowance shall not be left to reduce the roughing time, and too little allowance shall not be left to prevent material waste due to insufficient allowance.
- Rough. If it’s rough, you can also give it to an apprentice or a master who has not enough experience to operate it. The so-called roughing is to roughen the material and make the material smooth. Generally, a 0.2-0.5mm allowance is left for fine grinding. Too much allowance is not enough.
- Fine grinding. This work should be operated by experienced masters. Fine grinding is to carry out precision machining on roughened materials, so as to ensure the perpendicularity and parallelism of the workpiece and prepare for the finish machining. Fine grinding is convenient, so we should pay attention to the precautions of grinding machine processing. For details, please refer to the internal grinder processing safety specification.
- Finish machining. Master, must be master, must determine the order of machining, first understand the drawing requirements, determine the datum, select the fastest and most convenient processing steps.
- Surface treatment. Generally, there is no surface treatment equipment. We need to choose our own high-quality surface treatment plant, and then match the spindle speed and feed speed. If your lathe doesn’t work very well, it’s recommended to buy some sandpaper to make it. When making sandpaper, it’s suggested to make it according to the working direction of the lathe tool, so as to make the texture better.
In order to ensure that the die steel has good original precision – the quality of the original die steel, in the manufacturing process, it is necessary to reasonably select high-precision processing methods, such as EDM, WEDM, CNC machining, etc., and pay attention to the accuracy inspection of the die steel, It includes the machining accuracy, assembly accuracy of die steel parts and the accuracy of die steel through the test and acceptance work. It is necessary to select high-precision measuring instruments as far as possible during the inspection. For those die steel parts with complex surface structure, if the ordinary ruler and vernier card are used, the accurate measurement data can not be achieved. At this time, the coordinate measuring instrument should be selected To ensure the accuracy of measurement data.
Advantages of machining center
After the workpiece is clamped on the machining center once, the digital control system can control the machine tool to automatically select and replace the cutting tool according to different processes, automatically change the spindle speed, feed rate, the movement path of the cutting tool relative to the workpiece and other auxiliary functions, and complete the multi process processing on several surfaces of the workpiece in turn. And there are a variety of tool change or tool selection functions, so that the production efficiency is greatly improved.
① The selection of die steel materials should not only meet the customer’s requirements for product quality, but also take into account the cost of materials and their strength in the set period. Of course, the selection should be based on the type of die steel, working mode, processing speed, main failure forms and other factors. For example: the main failure mode of blanking die is edge wear, so it is necessary to select the material with high surface hardness and good wear resistance; the stamping die mainly bears periodic load, which is easy to cause surface fatigue crack and lead to surface spalling, so it is necessary to select the material with good surface toughness; the drawing die should select the material with low friction coefficient; the die casting die should be selected due to the effect of cyclic thermal stress For injection mold, when the plastic parts are ABS, PP, PC and other materials, the mold steel material can be pre hardened and tempered steel; when the plastic parts are high finish and transparent materials, the corrosion-resistant stainless steel can be selected; when the products are in large quantities, the quenching and tempering steel can be selected. In addition, it is also necessary to consider the use of mold steel materials with less affinity with the parts, so as to prevent the mold sticking from aggravating the wear of mold steel parts, thus affecting the quality of mold steel.
② In the design of die steel structure, the structure should be compact and easy to operate, and the die steel parts should have enough strength and rigidity; when the die steel structure allows, the corners of each surface of die steel parts should be designed as fillet transition as far as possible to avoid stress concentration; for the die, cavity, part of punch and core, the combined or inlaid structure can be used to eliminate stress Appropriate protection measures shall be taken for the structure of the long and thin punch or core with concentrated force; for the cold stamping die, devices shall be provided to prevent the blockage of the parts or waste materials (such as spring pin, compressed air, etc.). At the same time, we should also consider how to reduce the impact of sliding parts and frequent impact parts wear on the quality of die steel.
③ In the design, it is necessary to reduce the scope of disassembly and assembly when maintaining a certain part, especially when replacing the vulnerable parts.
The manufacturing process of die steel is also an important part to ensure the quality of die steel, The processing method and precision in the manufacturing process of die steel will also affect the service life of die steel. The precision of each part directly affects the overall assembly of die steel. In addition to the influence of the precision of equipment itself, it is necessary to improve the processing method of parts and the technical level of fitter in the grinding process of die steel to improve the processing precision of die steel parts If the overall assembly effect of the die steel can not meet the requirements, the probability of the die steel in abnormal state will be increased, which will have a great impact on the overall quality of the die steel.
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