Instrument for determining material flow through process equipment in high temperature environment

The patented instrument consists of a gamma radiation source and a detection unit located on the opposite sides of the technological facility. The detection unit fitted with Geiger-Mueller counters is protected from the undesirable effects of temperature by a perforated reflection metal cover. In order to compensate for the attenuation of gamma radiation by the metal cover, the inner wall of the counter case is coated with a layer of material with a high atomic number with a thickness equal to the range of secondary electrons. An example is given of the use of the instrument for the control of feeding a cement mix preheated to a temperature of 800 to 1000 degC into a revolving kiln. (Ha)