Thermal Imaging Cameras Ensure Material Quality in Industrial Rubber Calendering Processes

Thermal Challenges in the Production of Thin Rubber Layers

Precise temperature control plays a crucial role in determining material quality and suitability for further processing in industrial rubber manufacturing. Calendering systems are particularly important in the production of thin rubber layers for tire manufacturing. These systems guide preheated rubber compounds through several temperature-controlled rollers, reducing the material to a defined thickness. Depending on the application, layers as thin as 0.1 millimeters can be produced, serving, for example, as intermediate layers in the multilayer structure of vehicle tires.

The rubber compound is fed into the calender in a preheated state to ensure the necessary deformability. During the calendering process, heated and cooled rollers provide further temperature control. Typical process temperatures range from approximately 20 °C to 130 °C, depending on the processing stage. Temperature directly influences the flow and deformation behavior of the rubber and, consequently, the uniformity of the produced rubber sheet.

If the rubber compound falls below the required temperature range, it loses deformability and may tear during calendering. Excessively high temperatures, on the other hand, create the risk of premature vulcanization, causing the material to lose its processability. Both deviations result in material waste and negatively affect process stability.

Another challenge is maintaining a homogeneous temperature distribution across the entire working width of the calender. With roller widths of approximately 1.5 meters, local temperature differences can occur and affect material processing. At the same time, the actual width of the rubber sheet must be monitored, as the material does not always cover the entire roller width.

Continuous, non-contact temperature measurement is therefore essential for producing uniform rubber layers. Infrared temperature measurement enables early detection of thermal deviations and targeted adjustments to the heating and cooling processes of the calender rollers. This creates the conditions for stable material processing and reproducible product quality.

Improved Material Quality and Reduced Operating Costs in Rubber Calendering

The Optris Xi 80 enables comprehensive thermal process monitoring during rubber calendering and supports the production of uniform, high-quality rubber layers. By continuously capturing the temperature distribution, the thermal imaging camera detects critical deviations at an early stage. The acquired measurement data allows roller temperatures to be adjusted according to process requirements, reducing the risk of material cracks or premature vulcanization.

A key advantage over conventional infrared pyrometers is area-wide temperature measurement. While point-based monitoring of a 1.5-meter-wide rubber sheet may require at least eight individual pyrometers, a single IR camera provides a more complete thermal image of the monitored area. At the same time, the material distribution and width of the rubber sheet can be assessed thermally.

The reduced number of measuring devices lowers installation effort, cabling requirements, and maintenance costs. Instead of multiple infrared sensors, only one camera needs to be mounted, connected, and cleaned when necessary. Compressed air consumption for keeping the optics clean can also be reduced compared to multiple individually protected measurement points.

With the Xi 80, Optris offers a cost-effective combination of compact design, area-wide thermal imaging, and flexible system integration. In particular, the ability to operate autonomously without an additional PC, together with integration via analog process signals or software interfaces, simplifies implementation in automated production systems. PIX Connect software also supports the visualization and evaluation of temperature data.

Additional protective and mounting accessories are available for demanding production environments. An air purge collar prevents contamination from accumulating on the optics, while an optional water-cooled housing supports operation at elevated ambient temperatures. A shutter accessory provides additional protection for the camera optics.

By combining industrial-grade measurement technology, adaptable interfaces, and application-specific technical support, Optris provides a suitable foundation for the long-term optimization of automated rubber calendering processes.