Silicone’s in-built attributes enable the material to be used in multiple industries and applications. Industrial designers will sometimes find their prototype needs to be sealed, insulated or protected before the designs are finalised and signed off for mass production.
This is especially relevant for the food and beverage industry, as the material selection is crucial for products to conform to industry standards.
The opportunity and challenge
A design engineer for a coffee machine manufacturer approached Silicone Engineering to ask for a sealing solution for a new model they were working on.
They used a closed-cell elastomer to insulate and seal the lid top, roaster, and machine base. The designer found the material they were using at the time was too dense and was not allowing enough compressibility in the parts of the device they were looking to seal.
The lid function was the biggest challenge as the current design wasn’t compatible with the sealing material. In the application, they needed to align the top sealing gasket with the top of the roaster, they required a compressible seal with high-temperature resistance features that still allowed the lid to function to open and close.
The design was created with the consideration that the coffee beans would not come into direct contact with the silicone sponge gasket, so FDA compliant sponge was not at the forefront of the material selection. The coffee machine had a maximum operating temperature of 230°C.
Solution: kSil® GP 250
The customer suggested they send a sample of the current material to our laboratory team, and they then could deduce what material and density it was.
Once we received the material sample, our laboratory team tested the material to see what elastomer it was. With closed-cell sponges, densities get denser/stiffer as the material gets thinner, a side effect of closed-cell sponges.
After considering the application, design and what was previously used, our material engineer suggested using kSil® GP 250. The 250kg/mᶟ closed cell silicone sponge would be adept at withstanding the intense heat inside the unit and repeated cycle use whilst being soft and compressible enough to work within the current design confines.
One sample of each part was produced for the customer to approve and help finalise the prototyping stage.
The samples were tested and passed the consequent tests, the silicone gasket parts were signed off, and the customer then began proceeding with the initial order.