Non-Contact Measurement in Tyre Manufacturing

With the PyroCouple infrared temperature sensor

Calex infrared temperature sensor, model PC301MT-0,Leighton Buzzard, UK — ??Infrared temperature sensors from the Calex PyroCouple Series are being used by a major tyre (USA English: tire) manufacturer to detect the presence of hot rubber tyre material as it passes a point on a conveyor.

The tyre material is transported in two thin bands on a cooled aluminium conveyor. A Calex PyroCouple model PC301MT-0 infrared temperature sensor is positioned above the conveyor, and is aimed so that both bands are contained in its field of view.

The temperature of the tyre material is normally 75 ??C and the cooled conveyor surface temperature is typically 20 ??C.?? The sensor is connected to a Model??PPT245 DIN rail-mounted controller with a relay output that will switch at a chosen measured temperature (e.g. about 45 ??C).

The relay setpoint temperature is low enough that the relay will be triggered reliably despite the tyre material not completely filling the sensor’s field of view.

The system can therefore detect the presence of the tyre material and the time that the material starts and stops being present can be logged.

Speed data from the conveyor drive system is combined with the timings from the sensor thus the total length of tyre material passing the sensor can be calculated for each manufacturing period.


This system can also be used to detect the presence of a single band of product. If the sensor’s field of view is completely filled by the tyre material, then the temperature reading will also be accurate.

Tyre rubber has a high emissivity value, so the low-cost, fixed-emissivity PyroCouple Series of infrared temperature sensors is perfectly suitable. For other materials, please contact Calex for advice on the most suitable sensor.

The sensor measures an average temperature across its field of view.

Because the sensor can also view the cool conveyor as well as the hot tyre material, the measured temperature will be lower than the true temperature of the tyre material. However the reading is sufficiently accurate enabling the sensor to be used to detect whether or not the hot tyre material is present.

The PPT245 DIN rail-mounted controller will indicate the measured temperature and the setpoint temperature. It can also be configured to retransmit the measured temperature as a linear 0-10 V DC or 4-20 mA signal for connection to a data logger or other instrumentation.

It has another relay output that can be configured for control or alarm.

For more information, advice on choosing the most suitable sensor for your application, and for a quotation, please do not hesitate to contact Calex.

Calex has been providing high quality, cost effective temperature measurement and power conversion solutions for industries worldwide since 1973, . Their in-house design and manufacturing is focused on non-contact infrared temperature sensors and AC/DC power supplies. They also offer a wide range of complementary products including thermocouples, resistance thermometers, fibre-optic temperature sensors, indicators, controllers, SCADA systems, calibrators and DC/DC converters.

Calex Electronics Limited
PO Box 2
Leighton Buzzard, Bedfordshire
England LU7 4AZ

Tel: +44 (0)1525 373178 / 853800 (Lo-call: 0845 3108053)
Fax: +44 (0)1525 851319