How much do you know about CNC sheet metal processing?

Sheet metal processing is not only a key technology for sheet metal technicians to grasp, but also an important process of sheet metal products forming. Sheet metal processing is the traditional cutting blanking, blanking processing, bending forming and other methods and technological parameters, including a variety of cold stamping die structure and technological parameters, a variety of equipment working principle and control methods, but also includes new stamping technology and new technology. Sheet metal parts processing is called sheet metal processing.

Sheet metal processing

Sheet metal processing method

1 numerical control processing method

For sheet metal processing, there are mainly the following processing methods:

(1) Single stamping, that is, single stamping including: arc distribution, grid hole, etc.

(2) Continuous blanking can be divided into the same direction and multiple directions. Continuous blanking in the same direction mostly adopts the way of mold overlapping for processing, which is especially suitable for the processing of long holes. Multi-direction continuous blanking is more suitable for large hole processing with small die.

(3) Nibble processing, using small round die, small steps for arc continuous stamping processing.

(4) Single or continuous forming. Single forming is sheet metal processing with shallow stretch forming according to the nature of the mold. However, if the forming is larger than the size of the mold, continuous forming is required.

(5) Array forming. This processing method is suitable for the processing of multiple workpiece on a large plate, the type of workpiece may be the same or different.

Numerical control sheet metal processing technology characteristics

Numerical control application in sheet metal processing shows different advantages and characteristics, which can be summarized as follows:

(1) Easy to use and low input cost.

It has its own different advantages in the processing of all kinds of sheet metal parts, especially for the processing of complex shape or sheet parts can automatically complete the processing of parts. According to the requirements of the drawings, the holes of different sizes and shapes can be processed automatically, or the large holes and contour curves of various shapes can be produced by using small stamping die in the way of step by step. Add the simple structure of the mold for the existence of special processing technology of the sheet metal parts, such as: shallow drawing, flanging hole can also be processed. Compared with the traditional stamping, die is more simple, the processing range, significantly improve the processing ability, for mass production and is particularly suitable for various forms of product processing, for the processing enterprises to keep up with the pace of market development, meet the demand of the product is very good, but because of the reduction in cost of various aspects, to effectively improve the economic benefits of enterprises.

(2) Stable product quality and high machining accuracy.

For sheet metal parts of the processing of the workpiece has good flatness, punching and cutting accuracy, and brother Burr, forming quality is stable, the product has a good consistency.

(3) Effectively improving production efficiency.

Adopt automatic control system, can realize the small batch processing of the workpiece and the processing of different parts at the same time, and the processing speed is fast. Because of the reduction of the processing links behind the sheet metal parts of CNC integrated processing, greatly improve the production down, reduce the production cost input.

CNC stamping process

3.1 Blanking first, then processing technology

In the blanking, the first need to cut the plate, in accordance with the requirements of the dimensions of the parts of the plate cutting machine cutting blanking, and then nc program editing into the processing stage. As shown in figure 1 of the sheet metal parts processing, clamp plate after holding firmly to parts processing, pay attention to the way to trim the plank, four sides should have good verticality, if you want to processing sheet for 410 mm long and width of 400 mm rectangle, in a length of 2500 mm, width is 1250 mm on a big plate can work out this kind of rectangular sheet metal pieces, 18 material utilization rate under 9%. If the blanking time for a single part is 30 seconds, the total machining time is 9 minutes. In this process, a worker is required to place the cut and blanked sheet on the punch press for processing. The processing of a single workpiece requires 6 kinds of molds and 93 times of stamping. In addition to the time consuming of the loading and unloading parts, the processing of a single workpiece takes 1 minute.

3.2 Stamping blanking processing technology

Directly arrange the material on the entire plate, arrange the 18 parts neatly, and use the rectangular mould of the punch to separate 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 the completion of a clamping, there is a rectangular mold between the parts, to fully consider the size of the mold, namely the clearance of parts is 5mm, the material utilization rate is below 94%. This process requires seven molds, one more set of rectangular molds than the first process. In the process of cutting off the connection of the parts, the rectangular die stamping for 360 times, so that one piece of processing stamping to reach 2034 times to complete, the whole process takes 12 minutes of time. This kind of processing technology is relatively low precision parts, in the process of roundabout processing is easy to make the machine between the top and bottom of the rotary plate of the failure of the coil, there are safety hidden dangers in the processing, so in the cutting of parts in the state of low speed as far as possible. In addition, because there are micro connections in the parts, it is necessary to burr the connections in the later stage after finishing the machining.

Problems and countermeasures in CNC sheet metal processing

4.1 crushed

The main cause of crushing is the existence of sundries on the material surface, or sundries in the tool or the tool tray turret, or the unreasonable setting of the program, the tool clearance is too large and so on. In this regard, air guns or rags can be used to clean the surface of debris, adhere to the prop or turret whether there is debris and clean. The clearance of the lower die should be selected reasonably according to the thickness of the plate, and the tool should be demagnetized after grinding.

4.2 scratch

The scratches are mainly caused by the scratches on the materials, or the workers' scratches in the process of loading and unloading the materials, or the scratches on the molds. In this regard, for incoming material with serious scratches will not be used, in the process of loading and unloading chat, it is best to have two workers to lift or put the material vertically. During burr polishing, do not stack the workpiece together for polishing. In addition, the workpiece should be placed neatly and smoothly, and the height of each layer should be appropriate.

4.4 deformation

The main cause of deformation is the low mold die, the mold see too close to each other, deformation occurred in the production process. For deformation caused by such reasons, the lower die height can be increased. Note that the two high lower dies cannot be installed together. There is a certain distance between the punching position and the gripper. Punch the meshes with a perforated knife as much as possible. In addition, the processing order can be adjusted, first cutting edge and then punching mesh processing.

The application of NUMERICAL control in sheet metal processing opens up a new way for sheet metal processing and makes the machine tool sheet metal processing have a wider range of processing and development prospects. With the development of NUMERICAL control technology, sheet metal processing calculation and processing equipment are also developing toward the direction of linkage and composite processing. Numerical control system shows the trend of intelligent and scientific development, which plays a full role in the development of China's processing and manufacturing industry.