If you are looking for any information about calendering process for silicone then read this guide.
It covers everything about silicon rubber calendering process – Let’s find out.
Silicone Rubber Calendering
Silicone Rubber Calendering Process
Silicone rubber calendaring refers to a mechanical process. In this process, silicone rubber passes through a series of heated rollers. This result in high strength and uniform thickness sheet formation.
An option exists to add other materials in the composition to strengthen the properties of silicone rubber.
Step 1: Feeding
In this stage, the silicone rubber in the granules form remains within the hopper. You can add up other materials to the hopper. The materials you add depend on the final properties you want to achieve in the end product. You can add the following materials to the silicone.
- Cotton
- Fiberglass
- Nylon
- Polyester
- Nomex
- Monofilament Blends
You can also change the proportion or percentage of the material you add to silicone rubber. From the hopper, they get into another component. This stage refers to feeding.
Silicone Rubber Calendering
Step 2: Mixing
The next step in silicone rubber calendering is mixing. The materials from the hopper get transferred into the screw. This screw exists right below the hopper.
A screw mixer comprises a long hollow shaft containing a screw in either a clockwise or anticlockwise direction. These screws rotate throughout the shaft within a vessel.
The screw mixer homogeneously mixes the material and conveys the material in the forward direction.
You can also tweak the speed of the mixer, and it also depends on the thickness of the material composition. If it gets mixed quickly, then you can increase the speed. If the material is thicker, you can decrease the rate to give more, resulting in a homogenous mix.
Step 3: Conveying
Conveying is the function of a screw mixer. It conveys the silicone rubber composition to the steel rollers. The number of rollers that exists in a machine varies. Some contain three, and some have more than three. When it is conveyed to the roller, the next stage begins.
Step 4: Heating & Extrusion
Calendering Process for Silicone Rubber
The heat mainly comes through the steel rollers. The heating element is within the rollers. You can control the temperature setting as per requirement. This heat causes the material to pass through the rollers easily.
The roller then causes the material extrusion. The space between the rollers determines the end thickness of the sheet. You can control the thickness of the material better by tweaking the distance between consecutive rollers.
The clockwise and counterclockwise rotation of the roller leads you to the homogenous, uniform, and high-strength sheet.
Step 6: Embossing
After the heating and extrusion through several series of rollers now come embossing. You can put on the logo, message, or any precautions by embossing. This technique creates a noticeable raised pattern from the surface of the sheet.
By doing this, you can take branding to the next level. An option exists to create the custom logo through embossing to personalize the silicone rubber sheet.
Step 7: Cooling
After the embossing has ended. Now you need to place the sheet to allow it to cool down. As the cooling proceeds, the properties of the material become strengthened. Cooling is essential because, without cooling, you can experience deformation and non-uniformity in the end product.
Step 8: Discharging
In the end, stage, there comes discharging. The sheet from the silicone rubber calendering process comes out from the machine. Now it is ready to ship anywhere you want.
Conclusion: Silicone Rubber Calendering
Now you know everything about silicone rubber calendering. You can follow the above stages to carry out the process conveniently. Suppose you have any questions or want to share your thoughts on it. Feel free to comment in the comment section. We would love to hear your feedback and assist you in this regard.
More Resources:
Silicone Manufacturing – Source: LegenDay
Silicone Rubber – Source: Science Direct