Injection runners are an important part of an injection mold, responsible for directing molten plastic from the nozzle of the injection molding machine into the mold cavity to form the desired plastic product. The following is a detailed introduction to the types, characteristics, processing technology, function, optional materials, characteristics of injection molding runners for different materials, and Frequently Asked Questions (FAQ).
1. Types of injection molding runners
Linear runner: simple structure, smooth flow, suitable for molding parts smaller, more dense row of injection molding products.
Ring runner: the runner in the mold is set into a ring, when molding, the plastic flows from the runner between the ring and the hollow cavity of the product, suitable for the production of large injection molded products.
Branched Runner: By dividing the runner into small branches, the plastic is less likely to be twisted and deformed as it enters the product.
Hot Runner: Able to adiabatically deliver the thermoplastic melt near or directly into the mold, divided into various types such as hot tip, sprue and valve.
2. Injection Molding Runner Characteristics
Structural diversity: different types of injection molding runners have different structures and characteristics to adapt to different injection molding needs.
Flowability: When the injection molding runner is properly designed, the plastic can flow smoothly and fill the mold cavity.
Temperature Control: For hot runner systems, temperature control is critical to ensure that the plastic remains molten within the runner.
Pressure transfer: injection molding runners can effectively transfer the pressure of the injection molding process to ensure that the plastic is evenly distributed in the mold cavity.
3. Injection Molding Runner Processing Technology
Mold design: According to the demand of injection molded products and the specification of injection molding machine, design a reasonable mold structure, including the design of runners.
Runner processing: use machining or EDM and other methods to make precise runners in the mold.
Installation of hot runner system: For hot runner system, heating elements, temperature sensors and control system etc. need to be installed.
Debugging and Optimization: During the injection molding process, the runners are debugged and optimized to ensure the quality and productivity of the injection molded products.
4. The role of injection molding runner
Guide the flow of plastic: guide the molten plastic from the nozzle of the injection molding machine to the mold cavity.
Control plastic filling: By adjusting the shape and size of the runner, the filling speed and sequence of plastic in the mold cavity can be controlled.
Balance pressure: Ensure uniform distribution of plastic in the mold cavity to avoid defects such as bubbles and depressions.
Material saving: Reasonable runner design can reduce the waste of plastic and improve the utilization rate of material.
5. Optional materials for injection molding runners
Mold steel: mold steel with high hardness, high wear resistance and high corrosion resistance is the main material for injection molding runners.
Heat-resistant alloy: For hot runner systems, heat-resistant alloy materials with high thermal stability and corrosion resistance are required.
Injection Molding Runner FAQ
1. How to choose the right type of injection molding runner?
A: Choosing the right type of injection molding runner requires consideration of factors such as the size and shape of the molded product, the material, and the specifications of the injection molding machine. Generally speaking, for small, simple structure of the injection molded products, you can choose linear or branched runner; for large, complex structure of the injection molded products, it is more suitable to choose ring or hot runner.
2. what is the design principle of injection molding runner?
A: The design principles of injection molding runners include: to ensure that the plastic can flow smoothly, to avoid dead ends and stagnation; to maintain the temperature stability of the runner, to avoid premature solidification of the plastic in the runner; to minimize the size and length of the runner, in order to reduce the waste of plastic and recycling costs.
3. What are the advantages of hot runner systems?
A: Hot runner system has the following advantages: it can save material, energy and labor; improve the quality and productivity of injection molded products; shorten the molding cycle; expand the application range of injection molding process.
4. injection molding runner in the use of common problems?
A: injection molding runner in the use of common problems include: gate residue protruding or drooling drip, improper temperature control leads to plastic degradation or burning, runner obstacles or dead ends lead to uneven filling of plastic and so on. These problems need to be solved by optimizing runner design, strengthening temperature control and regular maintenance.
In summary, injection molding runner is an important part of the injection mold, its type, characteristics, processing technology, role and optional materials, etc. need to be based on the needs of injection molded products and injection molding machine specifications for reasonable selection and design. At the same time, in the use of the process need to pay attention to the solution and prevention of common problems, in order to ensure the quality of injection molded products and production efficiency.
