In the process of machining China Mechanical Parts, sometimes the stamping parts have some burrs of different sizes, which have a certain impact on the quality of the products. So what is the cause of burrs in Chinese mechanical parts?
First, the knife edge is blunt. The edges are blunt or bruised and can produce burrs. Factors affecting the blunt edge are:
1. The material of the convex and concave molds of the mold and its surface treatment state are poor, and the wear resistance is poor;
2, the die structure is poor, the rigidity is poor, causing bruises;
3, the operation is not timely lubrication, wear and tear;
4, did not timely sharpen the cutting edge.
Second, the gap. A burr can be generated if the punching gap is too large, too small or uneven. The following factors affect the excessively large, too small or uneven gap:
1. Mold manufacturing error, the processing of die parts does not conform to the drawings, and the parallelism of the bottom plate is not good;
2, the mold assembly error, the guide part of the gap is large, the convex and concave mold assembly is different;
3. The precision of the press is poor. For example, if the gap of the guide rail is too large, the parallelism between the bottom surface of the slider and the surface of the table is not good, or the perpendicularity of the stroke of the slider and the surface of the press is not good, and the rigidity of the table is poor. Deflection occurs during cutting, which can cause changes in the gap;
4. Installation error, such as the surface of the upper and lower plates of the die is not wiped clean during installation or the fastening method of the upper die of the large die is improper. The upper and lower die of the die are installed with different hearts (especially without the guide column die) and the working part is inclined;
5. The structure of the die is unreasonable, the rigidity of the die and the working part is not enough, and the punching force is not balanced;
6. The steel plate has a large curvature and the steel plate is not flat.
Third, improper punching status
If the blank (including the intermediate part) is not in good contact with the punch or the die, when the trimming is performed at a relatively high level of trimming, the part height will be lower than the relative height of the positioning, and the shape of the part during the blanking process. A burr is produced by not conforming to the shape of the cutting edge.
Fourth, the craftsmanship of the parts is poor
Shapes with complex or convex or concave sharp corners are prone to burrs due to excessive wear.
V. Material does not conform to the process regulations
If the thickness of the material is seriously out of tolerance or the wrong material is used (such as the wrong steel grade), the relative gap is unreasonable and the workpiece is burred.
The above is the reason for the burrs of Chinese mechanical parts. I believe everyone has already understood. Chinese mechanical parts burrs are usually produced in sheet metal blanking, which is generally difficult to avoid. By improving the processability of the parts and improving the stamping conditions, burrs can be avoided or reduced.