From sheet metal to part forming, this process involves many aspects: steel coil manufacturing? Storage and transportation? Cutting processing? Parts manufacturing? Assemblies, there will be different defects in all aspects of this long supply chain. Once the defects are generated, not only the loss of waste products, but also how to improve and stop losses in a timely manner is a more important issue. In the past, we have analyzed some defects (such as, etc.), and today we will talk about the troubleshooting and disposal of several common parts defects. Black spot on the surface of the part Defect name: stamping black spot Material type: hot-dip galvanized CQ material (typical grade DC51D+Z) Defect law: black spots with similar appearance at each part fixed position Troubleshooting ideas: 1. Confirm the association between defects and parts manufacturing; 2. Confirm the microscopic morphology, and the microscopic appearance is shown as a scratch defect; 3. Confirm the consistency between the materials and the drawings. The paper requires the passivation material, but the actual supply of uncoated oil rolls is likely to cause local scratches. 4. Confirm the thickness of the material, and the fluctuation of the thickness of the material (ultra-thickness) will cause the cavity gap to become smaller, resulting in local scratches; 5, confirm the state of the mold, the mold is rough, the assembly accuracy is abnormal, the lubrication is poor, etc., similar scratches will occur; Part color difference Defect name: color difference Material type: galvanized CQ material (typical grade DC51D+Z, SECC, etc.) Defects: There are significant differences in the color of parts produced by different batches of materials. Troubleshooting ideas: 1. Confirm the product category. The corrosion resistance of electro-galvanized and hot-dip galvanized products is similar, but the color is quite different; 2, confirm the type of surface treatment, fingerprint resistance, phosphating, passivation color will be different; 3. It is a normal phenomenon that there is a slight difference in color between the same products of the same steel mill. In addition to the color difference between the cold-rolled series of products, there is no requirement for other products; 4, do a good job of communication, confirm the use, non-appearing parts, follow-up painting parts, color differences do not affect the design function. The cup is not round and has bumps Defect name: the cup part is not rounded, and the stretched position has uneven streaks Type of raw materials: Pu cold DQ material (typical grade DC03, SPCD, etc.) Defect law: abnormal stamping with a certain steel coil, normal after changing the coil Troubleshooting ideas: 1. Confirm the drawing requirements. The DQ steel grade is too low for this part. At least DDQ steel grade (DC04) is used in normal conditions; 2, confirm the inventory time, DQ material inventory time is too long will lead to aging phenomenon, performance degradation is prone to tensile strain marks (orange peel, slip line); 3. If there are n values ​​and r worthy on the purchase of the spot warranty book, pay attention to the indicator, the higher the better, these two indicators are high for the cup forming; Conclusion The above are several common defects in the manufacture of parts. The main ideas for investigation are from the consistency of material selection and drawing, the inventory cycle is not exceeded, and the conformity of categories, etc. An exception must be an abnormal point. Finding an exception point solves the problem. Ningbo Zongchi Machinery Technology Co., LTD , https://www.zcdiecastservice.com
