Sequential Co-Extrusion & All Rubber Extrusion
This method combines 3-D blow molding with sequential co-extrusion, and consists of extruding two different materials (e.g., a rigid polyolefin with a soft thermoplastic vulcanizate). Coi Rubber has the perfect method to provided you with extruded products which will meet your application and demand.
Using this example, the soft thermoplastic vulcanizate would be extruded, followed by the rigid polyolefin, followed again by the soft thermoplastic vulcanizate. This allows a parison with different sections of material in the extrusion direction to be produced. This process is also commonly referred to as a “hard-soft-hard” process.
An inclined clamp is moved in coordinates while the parison, that has a smaller diameter than the article diameter, is placed into the mold cavity in such a way that the remaining pinch line length is reduced to a minimum. Then the mold is closed and the parison is inflated onto the cooled walls of the mold where the plastic cools down, solidifies, and sets the part shape. Finally the mold is opened and the part removed.
Benefits of This Process
- Substantial savings (material, energy, capital, cycle times, etc.) can be attained.
- Flash is significantly reduced and easily removed.
- Parts with very complex shapes can be molded.
- Clamping forces are reduced.
- Refinishing work on outer article diameter is eliminated.
- Improved quality due to more consistent wall thickness distribution and the elimination of weak areas in pinch lines.
- Smaller extruders can be used or larger parts can be molded.
- Less energy is spent in grinding or recycling flash.
- Less degradation of sensitive materials.
- Dual material co-extrusion that offers specific physical properties.
- Parts with different flexibility/stiffness in desired sections are feasible.
Rubber Extrusion / Edge-Trim
We are experts in u-channel extrusions, and we specialize in supplying extruded rubber shapes, extruded rubber seals and extruded rubber profiles. We also stock rubber extrusion for many applications. The standard profiles include U-Channels, P-profiles and other unique shapes. Common uses for rubber extrusion are sealing, noise control, vibration control and decorative trim. The elastomers used in our standard rubber extrusions are either weather resistant EPDM or SBR. Silicone, Neoprene, Viton and Buna-N are also available if your unique application requires a higher level of performance. Custom compounds and profiles are our specialty.
Extruding Rubber Sponge
Extruding Rubber Solids
Extruding Rubber Dual Durometer
– Wire Carrier
– Clip Carrier
-HAT (heat activated tapes)
Extrusions custom shapes and Secondary processes