Thermocouples For High Temperature Radiant Panels

Problem:

A customer used a Watlow® bayonet style thermocouple in conjunction with a radiant panel for a food frying operation. The unusual thing about this application was the radiant panels were mounted in an insulated oven with the panel's back running at 1050°F (565°C). This is too high a temperature for our standard thermocouple. In a very short time, the spring on the bayonet thermocouple relaxed from the high heat and the thermocouple could not maintain contact with the radiant emitters. The thermocouple failure caused the panel to continue heating even though the desired cooking temperature was reached. It was discovered no readily available springs existed that could withstand the application temperature.

Solution:

This problem was resolved by designing a new style mineral insulated thermocouple for this application. The thermocouple has a small tab on the junction end that holds the thermocouple in place to assure continuous contact with the emitter panels. The thermocouple was inserted into the radiant panel from behind and the tab twisted 90 degrees so it cannot pull out. It has worked very well to date and can be designed in any thermocouple type now offered by Watlow.

From initial inquiry to shipment of the first thermocouples took less than 48 hours. The quick turn around by our engineers prevented a loss of time and money on the job.