Hinge Stamping Die Processing Tips_Hinge knowledge_Tallsen 1

In the process of mold manufacturing and production, encountering bending parts of thicker plates (with a thickness of 2mm to 4mm) is a common challenge. To address this issue, it is important to develop a more suitable scheme and structure for the stamping process, mold design, and manufacturing.

The specific part under consideration is a middle hinge for a certain type of refrigerator. It is made from Q235 material with a thickness of 3mm, and the annual output is 1.5 million pieces. The requirements for this part include no sharp burrs or edges, a smooth surface, and an unevenness not exceeding 0.2mm.

The middle hinge plays a crucial role in connecting the upper and lower doors of the refrigerator. It needs to bear the weight of the upper door and the load inside the door. It also needs to ensure the flexibility of opening and closing the door while maintaining the thickness and verticality of the sheet metal.

The traditional process for manufacturing this part involves three steps: blanking, punching, and bending. However, this process has several issues. Firstly, the composite mold used in the design often leads to problems such as cracked punches, large burrs on one side of the product, and broken upper punching blocks. Secondly, the bending process results in displaced parts and unevenness at the bend, affecting the appearance and verticality of the part. Thirdly, the traditional process requires an additional shaping process, increasing production costs and the risk of product obsolescence. Lastly, using all four processes in one mold limits the production capacity and makes it challenging to keep up with the order quantity.

To resolve these issues, a new processing process is proposed. The new process involves the following steps: blanking punching, bending, and separation. The blanking and punching processes are combined using a flip-chip composite mold, allowing for the simultaneous production of two parts. This eliminates the problem of large burrs on one side of the punch and ensures a balanced pressure distribution. In the bending process, a one-bend-and-two structure is adopted, with the part being rotated and positioned using the four U-shaped holes from the previous punching step. The mold frame controls the flatness of the part, and the lower unloading plate shapes and flattens the product, ensuring verticality and flatness. The new process eliminates the need for a separate shaping process, reducing production costs and eliminating the risk of product obsolescence. Additionally, by reducing the number of processes from four to three, the production capacity is increased.

Comparing the production costs of the new and old processes, it is evident that the new process results in significant cost savings. The new process saves on labor costs and electricity bills due to the reduced number of processes and increased production efficiency. The total annual cost savings for this part amount to 46,875 yuan, making it a more cost-effective solution.

In conclusion, the new processing process successfully addresses the challenges encountered in the traditional process for manufacturing the middle hinge. By adopting a 1 mold with 2 pieces method and incorporating structural changes such as the use of small guide posts and guide sleeves, the issues of displacement, non-vertical bending, and punch tearing are eliminated. The implemented mold design has proven effective through continuous production of 3 10,000 pieces. This experience serves as a reminder that continuous learning, innovation, and the application of new knowledge and skills are essential for future success in an ever-changing technological landscape.