The blister tray for hardware and electronic parts has high requirements for mold precision. How to avoid mold release deformation or burrs?
Publish Time: 2025-03-31
In the field of hardware and electronic parts packaging, the dimensional accuracy of the blister tray directly affects the positioning accuracy and protection performance of electronic components. Since these parts often have precise dimensions and fragile characteristics, the precision requirements for blister molds are particularly stringent. Unreasonable mold design or improper process control can easily lead to product mold release deformation, burrs and other defects, which not only affect the appearance quality, but also may cause interference problems during the assembly of electronic parts. To solve these quality risks, it is necessary to systematically optimize mold design, material selection, process parameters and other aspects.
Mold design is the primary link to ensure demolding quality. For blister tray for hardware and electronic parts, the mold usually needs to be processed by high-precision CNC, and the dimensional tolerance of key parts should be controlled within ±0.05mm. The design of the parting surface is particularly critical, and the reasonable parting line position should avoid the main functional area of the product, such as the positioning column or buckle part of the electronic parts. The setting of the draft angle needs to balance the demoulding smoothness and dimensional accuracy. It is generally recommended to keep it between 3°-5°, and it can be appropriately increased to 7° for deep cavity structures. The cooling system design of the mold must be uniform. The use of conformal cooling water channels can significantly reduce product warping caused by uneven cooling. In terms of mold surface treatment, mirror polishing or Teflon coating can effectively reduce demoulding resistance and reduce the risk of product strain.
Material selection directly affects the demoulding performance of the product. It is recommended to use materials with high hardness and good wear resistance such as P20 or 718H steel for mold steel. For high-volume production, stainless steel such as S136 with higher hardness can be used. The selection of blister sheets is equally important. PET materials have become the first choice for hardware and electronic packaging due to their excellent dimensional stability, but it should be noted that the raw materials of different suppliers may have differences in shrinkage. If necessary, mold verification should be carried out. For pallets with anti-static requirements, the proportion of antistatic agent added needs to be precisely controlled. Excessive addition may cause the material toughness to decrease and increase the risk of cracking. In terms of material thickness selection, 0.3-0.8mm is a common range. Although thicker materials have higher strength, they require higher molding temperatures and longer cooling times.
Optimization of process parameters is the key to controlling demolding quality. The temperature of the sheet needs to be precisely controlled during the heating stage. Too high a temperature will cause the material to overstretch, and insufficient temperature will cause incomplete molding. During vacuum adsorption, the coordination of the exhaust rate and the holding time is crucial. Too fast exhaust may cause the material to be too thin locally, while insufficient holding will cause the product to rebound and deform. Temperature control in the demolding process is particularly critical. It is recommended to maintain the mold temperature between 40-60℃, which can ensure that the product is fully formed without causing stress concentration due to excessive temperature differences. For products with complex structures, segmented demolding or auxiliary ejection mechanisms, such as pneumatic ejectors or mechanical push rods, can be used to ensure that the product is evenly force-demolded.
Quality control during the production process should also not be ignored. A regular mold maintenance system should be established, including cleaning, lubrication and dimensional inspection, especially for high-wear areas such as trimming edges. Use optical measuring instruments or three-dimensional measuring machines to conduct full-size inspections on the first product to ensure that key dimensions such as positioning hole spacing and cavity depth meet the requirements. For the burr problem, in addition to maintaining the sharpness of the mold edge, it can also be improved by optimizing the punching pressure and adjusting the trimming temperature. The introduction of an automated visual inspection system can monitor product quality in real time, and promptly detect and remove defective products.
With the development of intelligent manufacturing technology, some innovative processes are being applied to the production of high-precision blister trays. In-mold trimming technology combines the molding and trimming processes into one, significantly improving dimensional accuracy and production efficiency. The application of 3D printed conformal cooling molds solves the problem that traditional linear cooling channels are difficult to evenly cool complex structures. The introduction of digital simulation technology can predict possible deformation areas before actual production and optimize mold design and process parameters in advance. The application of these new technologies provides new solutions for improving the quality of blister trays for hardware and electronic parts.
To ensure the demolding quality of blister trays, it is necessary to establish a full-process quality control system from design to production. Strengthen early communication with customers to fully understand the packaging requirements of electronic parts; maintain technical cooperation with raw material suppliers to ensure the stability of material performance; improve parameter monitoring and data traceability during the production process to provide a basis for quality analysis. Only through such a systematic approach can we continuously and stably produce high-precision blister trays that meet the packaging requirements of hardware and electronic parts.
