3.1 cutting first and then processing
Dongguan CNC machining plant in the blanking, first need to cut the plate, according to the size requirements of the parts, use the shears to cut the plate, and then edit the NC program to enter the processing stage. In the process of sheet metal parts, clamp the plate firmly and then process the parts. Pay attention to trimming the plate when cutting. Four sides should have good perpendicularity. If the plate to be processed is a rectangle with a length of 410mm and a width of 400mm, 18 pieces of such rectangular plates can be processed on a large plate with a length of 2500mm and a width of 1250mm, and the material utilization rate is less than 9%. If the cutting time of a single part is 30 seconds, the total processing time is 9 minutes.
In this process, Dongguan numerical control processing plant needs a worker to place the plate after cutting and blanking on the punch machine for processing. The processing of a single workpiece requires six kinds of molds and 93 times of stamping. In addition, the time-consuming of loading and unloading the workpiece, the total processing time of a single workpiece is 1 minute.
3.2 stamping process
Dongguan numerical control processing plant directly arranges 18 parts on the whole plate, and uses the rectangular die of the punch to cut off each part separately. However, in order to prevent the parts from falling off, the micro connection should be reserved to keep the plate in a whole state. After one-time clamping, there is a rectangular mold between the parts. The size of the mold should be fully considered, that is, the gap between the parts is 5mm, and the utilization rate of materials is below 94%. This kind of processing technology needs to use seven kinds of molds, and uses a set of rectangular molds more than the first one. In the process of connecting and cutting parts, the rectangular die is punched 360 times, so that the stamping of one part can be completed 2034 times, and the whole process takes 12 minutes. This kind of processing technology method is relatively low precision parts, in the process of circuitous processing, it is easy to make the machine between the upper and lower turntable coil fault, there are security risks in the processing, so it is best to cut off parts in a vulgar state. In addition, because of the existence of micro connection in the parts, it is necessary to grind the burr at the connection after machining.
Problems and Countermeasures in NC sheet metal processing
4.1 crush injury
The main causes of crush injury in Dongguan CNC machining plant are the existence of debris on the surface of the material, or in the cutter or turret, or the unreasonable setting of the program and the excessive tool clearance. In this regard, air gun or rags can be used to clean up the debris on the surface, and whether there are debris in props or turrets should be insisted on and cleaned up. The gap of the lower die should be reasonably selected according to the thickness of the plate, and the tool after grinding should be demagnetized.
4.2 scratches
The scratch is mainly caused by the scratch on the material, or the worker's scratch in the process of loading and unloading, or the scratch on the mold. In this regard, it is not allowed to use the material with serious scratch. In the process of loading and unloading, it is better to have two workers to lift or put down the material vertically. In burr grinding, pay attention not to stack the workpiece together for grinding, in addition, the workpiece should be placed neatly and smoothly, and the height of each layer should be appropriate.
There are mainly too low mold, mold see too close to each other, in the production process of deformation. For the deformation caused by such reasons, the height of the lower die can be increased, and the two high lower dies cannot be installed together. There is a certain distance between the punching position and the clamping claw. As far as possible with a multi hole knife punching mesh processing. In addition, the processing sequence can be adjusted, cutting edge first and then punching mesh.
5 Conclusion
The application of Dongguan numerical control processing plant in sheet metal processing opens up a new way for sheet metal processing and manufacturing, and makes the sheet metal processing of machine tools have a wider processing range and development prospect. With the development of numerical control technology, sheet metal processing calculation and processing equipment are also developing in the direction of linkage and compound processing. Numerical control system presents an intelligent and scientific development trend, which plays a full role in the development of China's processing and manufacturing industry.