FTS – Furnace

A radiation thermometer system, using two sensors, provides a continuous true temperature of the reheat furnace load and with it the possibility of big savings in operation costs.

The Measurement

The first sensor, a radiation thermometer operating at a wavelength of 3.9μm, measures the apparent temperature of the furnace load. The output from this thermometer contains a component that is due to radiation from the hot background being reflected from the load. A second sensor measures the background temperature. The outputs from the two sensors are applied to a thermometer’s signal processor which continuously computes the true load temperature corrected for the background radiation.

The Application

High system measurement accuracy (typically better than +20°C/+36°F at 1000°C/1830°F) is obtained in gas-fired (natural/blast furnace/coke oven) steel reheat furnaces – even in the first heating zone. Similarly, high accuracy measurements can be achieved in many furnaces fired on light or heavy oil. Close consultation with Land Infrared is advisable for best results on oil-fired furnaces. The system is also suitable for use on a wide variety of other furnace applications where background reflections are affecting single sensor system measurements.