Silicone Extrusion: Innovations and Technologies for the Future of Manufacturing

Silicone Extrusion: Innovations and Technologies for the Future of Manufacturing

Extruded silicone products are now indispensable in our daily lives. The unique properties of silicone, which we will discuss further, make it a "high-performance" material. But how is this material processed? In the following sections, we will explain the silicone extrusion process, which allows for the creation of flexible, heat-resistant, and precise products that are in demand in many areas, such as medicine, the food industry, and construction.

But what ensures that the special requirements for silicone extrusion are met? The exceptional properties of silicone, along with specific technologies, play a crucial role in this process. You will learn more about these aspects in this article.
 

1. What makes silicone so special?

Silicone is an extremely versatile material that is ideal for demanding manufacturing processes such as extrusion, thanks to its outstanding properties. It is characterized by the following features of the finished products:

• Temperature resistance: Usable from -55 °C to 260 °C.
• Flexibility and elasticity: Adapts to complex geometries.
• Chemical resistance: Resistant to corrosion, chemicals, and UV light.
• Biocompatibility: Ideal for medical and food-grade applications.
• Electrical insulation: Well-suited for wires and electronics.
• Flame resistance: Special additives enable silicone to absorb a significant amount of heat during fires, allowing it to continue insulating electrical wiring for a certain period even in the event of a fire.

These properties make silicone indispensable in industries such as automotive, medical technology, electronics, and construction, as some complex products are difficult to achieve with other materials.
 

2. Silicone Extrusion: How Does the Process Work?

In silicone extrusion, the material silicone is pressed through a specially designed die to create profiles, tubes, hoses, or other complex geometries. This process offers high precision and flexibility for producing both standard and custom products.

The main steps of the process include:

1. Material Feeding: The controlled supply of raw material using piston feeder, strip feeding devices, or screw systems.
2. Extrusion: The material is shaped in an extruder, which consists of a cylinder, hopper, and screw.
3. Vulcanization: A highly efficient heat treatment ensures the shape stability of the product.
4. Cooling and Finishing: Final processes such as cooling, cutting, and packaging ensure compliance with product specifications.
    

3. Technologies for Silicone Extrusion

Choosing the suitable machines and heads is crucial for the quality and efficiency of the process. Machine manufacturers offer a variety of solutions tailored to the specific requirements of silicone processing:

Feeding Systems

• Piston Feeder: Ideal for low-viscosity and sticky materials, operates on the principle of stepwise advancement. A piston pushes the material into the extruder, ensuring a uniform and controlled feed.
• Strip Feeding Device: Used for supplying silicone mass in uniform strips, with or without separating films. This method is suitable for materials that are not very sticky and can be produced in an "endless" strip form.
• Conical Screw Feeding Systems: Designed for feeding block-shaped silicone. The conically shaped feed screws allow for continuous shearing as well as better mixing and are suitable for materials with varying flow properties.

Extruder

Modern rubicon silicone extruders offer a compact design and precise process control for pressure and temperature. They are suitable for both mono and co-extrusion, allowing for the production of complex products made from multiple materials.

Extrusion Heads

The extrusion head forces the raw material into the desired shape as it exits the silicone extruder, making it a crucial component of the process. There are various types of extrusion heads, including:

• Straight and sheathing heads for profiles and hoses: These ensure a consistent flow and are used for standard extrusion processes.
• Cross heads: These enable the coating or sheathing of wires, cables, and hoses.
• Double crossheads: These allow for two- or multi-layer extrusion, providing versatility for different product specifications and the production of complex profiles and products.
• Co-extrusion heads: These facilitate the simultaneous extrusion of different materials.
• Specialized heads: These allow for fine-tuning the flow rate and profile dimensions, offering flexibility for various product specifications.
• Strainer heads
• Rheometer heads
• Slot die heads

Silicone Gear Pump

The use of a gear pump in a silicone extrusion line offers several advantages:

• Even Flow: Ensures a smooth, non-pulsating flow, which is crucial for maintaining product quality and consistency.
• High Efficiency: Provides efficient transportation of silicone, even at high viscosity, thereby minimizing waste and energy consumption.
• Durability: Sturdy and capable of handling abrasive and corrosive materials.
• Precision: Offers precise control over flow rates and pressures for optimal product specifications.
• Reduced Heating: Helps preserve the properties of silicone by reducing the heating of the mixture.
• Improved Production Yield: Leads to a higher production yield and better dimensional accuracy of extruded profiles.

Vulcanization Systems

Rubicon's silicone vulcanization systems are high-performance infrared tunnels designed for both peroxide-cured and addition-cured silicones. The main systems include:

• Infrared shock tunnel: Ensures high shape stability and a uniform profile surface, directly placed after the extrusion head.
• Vertical top-down systems: Ideal for light to medium-weight products.
• Vertical bottom-up systems: Suitable for heavy profiles and processing small cross-sections at high speeds.
• Horizontal high-performance line: Provides efficient and even heat distribution and transfer for high-quality vulcanization.

Additionally:

Cooling Systems
After vulcanization, a cooling mechanism rapidly cools the material to preserve its properties and ensure product stability.

Cutting and Processing Tools
For the final shaping of the end product according to specifications, devices such as winders and cutting units are required, which can be integrated into the line for a continuous, automated process.

Quality Control Equipment
Inline quality control ensures that the product meets specified requirements, with integrated systems for measuring diameter, marking, and more.
 

4. Versatile Extrusion Processes

Silicone extrusion is exceptionally varied and covers a wide range of applications:

• Hose extrusion: For medical, industrial, and automotive purposes.
• Profile extrusion: For windows, doors, and technical insulation.
• Profile extrusion: Produces various cross-sectional shapes.
• Solid cord extrusion: Forms cylindrical rods or cords.
• Sponge cord extrusion: Results in cellular structured products.
• Strip extrusion: Produces uniform bands or strips.
• Wire and cable coating: Applies protective silicone layers.
• Multilayer hose extrusion: For hoses with multiple inner cavities.
• Custom extrusion: Tailored to specific requirements.
   

5. Why Companies Benefit from Silicone Extrusion

The increasing demand for durable, chemical-resistant, and customizable products offers many advantages to companies that use machines for silicone processing:

Advantages of Silicone Extrusion

• Efficiency: Automated processes ensure high production speeds.
• Precision: Perfect fit for complex requirements.
• Sustainability: Reduction of material waste and energy consumption.
• Market Flexibility: A wide range of applications encourages the development of new products.

Silicone extrusion is an essential component of modern manufacturing. With the suitable technology and innovative power, high-quality products can be developed that meet the highest standards and find applications across various industries.
 

Silicone Extrusion with rubicon

Whether standard profiles or custom extrusions, silicone is the material of choice for forward-looking solutions. Contact us now to create a tailored silicone extruder and benefit from our expertise in durable and flexible solutions!