Silicone molding is a manufacturing process that transforms liquid or semi-solid silicone raw materials into elastomeric products with specific shapes and properties. It serves as the backbone of producing everything from daily necessities (P.EJ., Utensilios de cocina) to high-precision industrial parts (P.EJ., focas). But with multiple molding techniques available, how do you choose the right one for your project, and what key factors ensure success?
1. A Comparison of 6 Core Silicone Molding Methods
Different silicone molding techniques are designed for specific scenarios—from mass production to small-batch customization. The table below breaks down their core features, aplicaciones, and key controls:
| Método de moldeo | Características clave | Aplicaciones típicas | Critical Control Parameters |
| Moldura de compresión | Alta precisión; adecuado para estructuras complejas; producción en masa | High-precision seals, juntas automotrices | Temperatura del molde (160–200 ° C), presión (5–50MPa), vulcanization time |
| Moldura de inyección | Alta eficiencia; low scrap rate; automatizado | Miniaturized parts (P.EJ., electronic buttons, conductive connectors) | Velocidad de inyección (staged control), mold vacuum exhaust, plasticization temperature |
| Extrusion Molding | Continuous production; equal-section profiles | Tubería, tiras de sellado, rubber hoses | Die design, barrel segmented heating, laser diameter monitoring |
| Gate Molding | Flexible; low-cost for small batches | Transparent crafts, Prototipos de moho, custom jewelry | Vacuum defoaming, layered infusion (Para partes gruesas) |
| Revestimiento & Impregnation | Delgado, uniform coverage; adheres to substrates | Fabric coating, PCB waterproof films, biomedical coatings | Coating thickness, adhesion (grid test), centrifugation speed (for impregnation) |
| Moldeo especial | Innovador; resuelve necesidades complejas | corredor frio: piezas sin desperdicio; 3D impresión asistida: texturas complejas; Co-moldeo: silicona + inserciones de metal/plástico | Aislamiento (corredor frio), tipo de resina (3D impresión), posicionamiento de inserción (comoldeo) |
2. Step-by-Step Guide to 3 Common Molding Processes
Para principiantes o aquellos que seleccionan un método, aquí hay un desglose lineal de tres flujos de trabajo ampliamente utilizados:
A. Moldura de compresión (Ideal for High-Precision Seals)
- Preparación de material: Pesar caucho crudo, relleno, y agentes vulcanizantes por fórmula; mezclar uniformemente a través de un refinador.
- Plastificación: Reduzca la viscosidad del compuesto Mooney utilizando el método de paso fino para mejorar la plasticidad..
- preformado: Corte el compuesto en espacios en blanco que coincidan con la forma aproximada del producto final..
- Mold Vulcanization: Place blanks into the mold; heat and press in a flat vulcanizing machine (160–200 ° C, 5–50MPa).
- Post-tratamiento: Recortar el exceso de material; conduct secondary vulcanization to remove volatiles and boost stability.
B. Moldura de inyección (Best for Miniaturized, Mass-Produced Parts)
- Feeding: Automatically feed granular or strip compound into the machine’s barrel.
- Plastificación: Heat the barrel to soften the compound (temperature varies by silicone type).
- Inyección: Use high pressure to inject the softened compound into the closed mold cavity.
- Packing & Enfriamiento: Maintain pressure until the compound is initially cured; cool slightly to set shape.
- Fundamento: A manipulator automatically removes the finished product—no manual trimming needed for most designs.
do. Extrusion Molding (Great for Continuous Profiles)
- Die Design: Customize the die opening to match the product’s cross-section (P.EJ., round for pipes, rectangular for strips).
- Calefacción & Extrusión: Heat the barrel in segments (front: plasticization; middle: constant temperature; rear: formación); push compound through the die.
- Escucha: Usar un laser diameter gauge to real-time check product dimensions and adjust extrusion speed if needed.
- Traction & Corte: Pull the extruded profile via a track system; cut it to the set length automatically.
3. Solución de problemas: Defectos comunes & Soluciones
Incluso con un diseño de proceso adecuado, pueden ocurrir defectos. A continuación se muestra una guía de causa y efecto para solucionar los problemas más frecuentes.:
| Fenómeno de defecto | Causa principal | Solución práctica |
| Agujeros de burbujas | Aire atrapado durante la mezcla; gas liberado durante la vulcanización | Usar antiespumante al vacío antes de moldear; Adoptar calentamiento en gradiente para la vulcanización. (evita la expansión repentina del gas) |
| Escasez de pegamento (Relleno incompleto) | Baja fluidez de la silicona; volumen de inyección de pegamento insuficiente | Aumentar la presión de inyección (para moldeo por inyección); optimizar la posición de la compuerta para mejorar el flujo; precalentar ligeramente la silicona |
| Superficie pegajosa | Vulcanización incompleta; contaminación de la superficie del molde | Extend vulcanization time or raise temperature; clean the mold with a solvent (P.EJ., alcohol isopropílico) antes de usar |
| Desviación dimensional | Uneven curing shrinkage; inconsistent mold temperature | Reserve a 1.5%–3% shrinkage allowance in mold design; ensure uniform mold heating (use temperature sensors) |
4. Material & Equipment Selection Guide
Choosing the right materials and equipment directly impacts product quality. Use this table to match your needs:
| Demand Scenario | Recommended Silicone Type | Supporting Equipment |
| Food-Grade Products (P.EJ., silicone spatulas) | FDA-certified liquid silicone | Vacuum casting equipment (avoids contamination) |
| High-Precision Seals (P.EJ., automotive oil seals) | Silicone with vapor-phase silica filler (aumenta la dureza) | Precision compression molding machine |
| Conductive Parts (P.EJ., electronic buttons) | Precipitation-method conductive silicone rubber | Vertical injection machine + static elimination device |
| High-Temperature-Resistant Parts (P.EJ., industrial pipes) | Phenyl silicone rubber (resists up to 300°C) | Extruder + laser diameter gauge |
5. Yigu Technology’s Perspective on Silicone Molding
En la tecnología yigu, we see silicone molding as a driver of product innovation—not just a manufacturing step. For clients in healthcare, hemos optimizado coating molding to create biocompatible silicone films for medical devices, asegurando 99.8% adhesion and meeting global safety standards. Para clientes automotrices, nuestro moldura de compresión process reduces seal defect rates to below 0.5% by refining temperature control and using high-purity fillers.
Looking forward, we’ll focus on two priorities: 1) Developing eco-friendly silicone materials that cut waste by 30% y 2) Integrating AI into moldura de inyección to real-time adjust parameters, boosting efficiency by 20%. We aim to make silicone molding more sustainable, preciso, and accessible for all industries.
Preguntas frecuentes
- Which silicone molding method is best for small-batch custom products (P.EJ., 50–100 unidades)?
Gate molding is ideal—it’s low-cost, flexible, and doesn’t require expensive molds. Use additive liquid silicone for high transparency (P.EJ., custom crafts) and vacuum defoaming to ensure quality.
- How to ensure food-grade safety in silicone molding for kitchenware?
Primero, select FDA-certified liquid silicone (no toxic additives). Segundo, use dedicated equipment (avoid cross-contamination with industrial-grade silicone). Tercero, conduct post-production tests (P.EJ., leachate testing) para cumplir con los estándares de seguridad alimentaria.
- What’s the main difference between compression molding and injection molding for silicone parts?
Compression molding is better for complex, piezas de alta precisión (P.EJ., focas) but has longer cycle times. Injection molding is faster (ideal for mass production of mini parts like buttons) and has lower scrap rates, but requires higher initial mold investment.