The development of the injection mold industry plays a decisive role in enhancing the production efficiency and quality of plastic products. Modern plastic part production relies on reasonable injection processes, advanced injection molds, and high-precision, high-efficiency injection equipment. With the advancement of Industry 4.0 and intelligent manufacturing, the mold industry is moving towards more intelligent and automated development, which not only improves production efficiency but also the quality and stability of products. Moreover, the trend towards high precision and personalized customization in injection molds enables mold companies to better meet the diversified needs of the market and consumers.
In the context of globalization, China's injection mold industry is facing new opportunities and challenges. With the continuous growth of domestic and international market demands, the investment in product design and research by mold companies will continue to increase, and market competition will further intensify. This requires mold companies to not only improve their technical level and innovation capabilities but also strengthen their service capabilities to adapt to rapid market changes and the diversification of customer needs. The development of the injection mold industry is not only crucial to the plastic products industry but also plays a role in promoting the modernization and internationalization of the entire manufacturing industry.
Despite the fact that some enterprises can achieve automatic mold gate cutting using existing technical means, these methods have various limitations:
Relying on the mold's opening and closing cycle to drive the gate cutting mechanism, the start and end times of the cutting tool cannot be flexibly adjusted due to restrictions. This results in poor gate excision quality, large rough edges, and a short cutter life.
Using the hydraulic neutron signal of the injection molding machine to drive the cylinder for action requires complex and costly modifications to the existing machine.
The traditional cylinder's large volume often cannot fit within the limited space of the mold. Enlarging the mold would necessitate the use of a larger injection molding machine, increasing production costs. These limitations restrict the large-scale application of automatic gate cutting in molds, leading to a reliance on manual gate cutting in traditional injection molding production, which bottlenecks the improvement of production capacity and cost reduction. A domestic Chinese company has developed an automatic control system that can be applied within the mold to solve this problem. This system not only enables automatic gate cutting within the mold but also addresses product molding defects, effectively reducing labor costs post-injection molding, and improving product quality. The automation of process control also enhances the stability and productivity of injection molding production.
Applications span various fields, including electronics, electrical, medical, automotive, and aviation industries.
Working Principle of In-Mold Heating System
The typical in-die heating system consists of a miniature high-pressure oil cylinder, an automatic control cutter assembly, a forming control system, and other auxiliary parts. The forming controller drives the micro-cylinder installed in the mold through a high-pressure power module according to the set cutting tool ejection and rollback times, which then drives the cutting tool mechanism to separate the gate from the product within the mold.
Advantages of Hot Gate in Mold
Gate Section Quality: The gate section is not smooth when using manual cold cutting methods. In-mold heating results in a smooth and flat gate section, significantly improving product appearance quality.
Automatic Separation of the Gate in the Mold Reduces Dependence on People: Traditional plastic molds require manual cutting and separation after the mold opens. Hot molds separate the gate before the mold opens, eliminating subsequent processes and facilitating production automation, thus reducing dependence on manual labor.
Reduce Human Quality Impact on Products: In-mold hot mold molding ensures consistent gate separation quality, while traditional manual gate separation cannot guarantee the same. Many high-quality products on the market are produced using in-mold hot molds.
Reduce Molding Cycle and Improve Production Stability: The automation of heat forming in the mold avoids unnecessary human actions in the production process and ensures quality consistency through fully automated mechanical cutting, giving it an incomparable advantage over traditional molds in mass production.
Several Important Links of In-Mold Heating System Import
Scheme Design: The reasonableness of the in-mold heating system's scheme design affects the life and stability of the system's operation. Comprehensive evaluation by professional engineers is required, considering product structure, forming materials, appearance quality requirements, mold structure, gate form, heating system settings, molding cycles, etc.
Machining Accuracy of the Mold: The cutting tool assembly in the in-mold heating system needs to repeatedly perform ejecting and backtracking actions. If the gap between the cutting tool and the cutting tool hole of the mold is too large, plastic can be squeezed into the sliding gap during molding or cutting tool ejection, leading to burring and increased resistance, which can cause the cutting tool to jam or fail to retract properly.
Operation of the Production Site: On-site personnel must operate strictly follow the operating procedure, or there may be oil leakage, cutting, or inaction.
In-Mold Heat Typical Application Cases Shared
For products with large fan-shaped gates, traditional gate removal methods such as electric pliers, cold stamping, or milling have high defect rates due to human factors. In-mold hot gates offer more flexible gate design, eliminating post-processing considerations, and are more conducive to injection molding filling and simplifying the molding process, ensuring product appearance, size, and deformation.
For products requiring a high gloss surface or electroplating, in-mold heating can save costs and improve or solve product appearance or functional issues.
For thin-wall decorative frame products, in-mold heating allows the product to complete gate and product cutting separation within the mold cavity, enabling mold opening and ejection only after product cooling, greatly reducing the molding cycle and improving production capacity.
