At Tire Technology Expo, which took place in Hanover in March 2026, Erhardt+Leimer presented a range of solutions for tire and rubber production – including EL.Tag. In addition to that system, the company also unveiled a solution with practical relevance to the calender line: EL-Thickness – the company’s new thickness measurement solution with a compact combination sensor.
In tire manufacturing, material thickness is far more than a basic quality parameter. At the calender, even small deviations can influence material consumption, downstream quality, and process stability. That is why reliable inline thickness measurement remains a key issue for manufacturers. Erhardt+Leimer’s latest variant of EL-Thickness addresses exactly this point by measuring material thickness directly on the calender, where the calendering process itself can be monitored in real time.
A compact measuring head with two sensor technologies
The core of the system is its compact combined measuring head. It integrates a laser triangulation sensor, which measures the distance to the rubber surface, and an eddy current sensor, which measures the distance to the calender roll through the rubber. The exact material thickness is calculated from the difference between these two values. This measuring principle enables highly accurate material thickness measurement against the calender roll while keeping the mechanical setup compact enough for direct installation on the machine.
Easy integration where space is limited
That compactness is one of the system’s strongest arguments. Space is always limited around the calender, and additional measurement technology is often judged not just by precision, but by whether it can be integrated without complicating the machine layout – especially when retrofitting existing equipment. According to Erhardt+Leimer, the EL-Thickness system can be installed directly on the calender, and due to its modular design and different connection options also supports easier integration into existing production environments.
Reliable performance under harsh operating conditions
The operating conditions at the calender make robustness just as important as accuracy. Heat, contamination and demanding ambient conditions are part of daily production reality. To address this, the optical sensor system is equipped with air cooling controlled by temperature sensors. This ensures stable measurement at temperatures of 50°C inside the sensor head even if the ambient temperature at the calender is higher. An integrated air pressure sensor monitors whether cooling is functioning correctly and whether the cooling air is reliably reaching the inside of the combination sensor. In other words, EL-Thickness is engineered not only for measurement performance, but for dependable use in the harsh environment of rubber processing.
The technical data underline the system’s industrial focus. EL-Thickness is designed for a standard material thickness measuring range up to 8mm, with up to 40mm available on request, and material widths of up to 5,000mm. Thickness accuracy is specified at up to ±10µm, with a displayed resolution of 1µm. The system can be configured with up to five permanently mounted measuring points, with more available on request, or with one traversing measuring point, depending on the application and machine concept.
From measurement to process intelligence
Measurement data from EL-Thickness can be used for different purposes. The system enables real-time calender control via customer PLC and can assign measured material thickness to the exact position on the roll. It is also fully integrated into Erhardt+Leimer’s ELQ data management environment. ELQ is designed to display, compare, archive and evaluate measured data from connected measurement systems, making thickness measurement part of a wider quality and production intelligence setup rather than an isolated measuring task.
A modular platform for different applications
Erhardt+Leimer’s thickness measurement platform covers different mechanical concepts and sensor technologies, including laser triangulation, chromatic-confocal, and interferometric methods for various applications. The calender-specific solution shown in Hanover takes that modular background and adapts it to the needs of tire and rubber production with a direct, compact measurement concept.
A further practical detail is maintainability. The thickness measurement system is combined with the AG 72 electrical drive, enabling it to switch between working and parking positions. This simplifies access during maintenance and reduces effort for operators and service teams. It is a small but important feature, because in production environments, usability often matters as much as measurement performance.
Strong interest at Tire Technology Expo
Following its appearance at Tire Technology Expo, EL-Thickness stands out as a well-targeted solution for manufacturers who want precise, inline thickness measurement directly on the calender without sacrificing robustness or integration capability.
