Cooling Rolls for Plastic Sheet Extrusion Processes
Plastic sheet production has extensive cooling requirements. As the extruded sheet comes out of the heated chamber and die, the plastic - being a poor heat conductor - retains Most of its heat. To achieve proper cooling for plastic sheet, double shell heat transfer rolls are used to draw heat away from the hot plastic sheet. By running the hot plastic sheet in an "S" pattern through three to five chill rolls (either horizontally or vertically) The plastic sheet can be brought down to an acceptable temperature. The quality of the chill rolls will dictate the sheet thickness, texture, and gloss of the plastic sheet surface.
Custom Plastic Cooling Roll Finishes
Plastic extrusion cooling rolls need to efficiently and quickly transfer heat. They should be fabricated with a hardened base metal to withstand "worm tracking" and other potential deformation consequences of the process.
Roll Technology supplies heat transfer rolls of various sizes with totally custom surface finishes to meet each customer's individual need. Completely defect free flawless optical mirror finishes measured to 0~1 Ra are common in the industry, as are textured surfaces (matte and satin) produce to varying degrees of roughness on the product.
Plastic Cooling Roll Solutions
We address many issues with respect to engineering the correct roll for its application including deflection, fluid flow, expansion and contraction of the heat transfer roll, final geometry as well as other parameters which make up proper design and finish. Roll Technology works with your engineering and maintenance staffs to offer the following:
- A full range of roll diameters and face lengths.
- Mono-flow or dual-flow heat transfer designs.
- Precision finishing to your exacting specifications.
- Bearing selection and installation for close tolerance run~out requirements.
- Convex, concave or extremely "flat" finishing specifications.
Common surface finishes that are available:
- Flawless pit-free optical mirror.
- Fine, medium or coarse dull, gray matte surfaces.
- Fine, medium or coarse pre-blasted satin surfaces.
- Commercial polished surfaces from 4-16 Ra.
Companies worldwide depend on Roll Technology's expertise and experience in solving problems inherent in the web processing industry.