Calibration of Radioisotope Level Gauge Detector

In accordance with regulatory standards, to meet the requirements of legislation in the field of industrial safety and ensure the quality of fiberglass products, as well as to confirm the correct operation of the measuring instrument, accurate calibration of the radioisotope measuring instrument is necessary.The aim of this work is to develop a method for testing the tightness of the Cesium-137 ionizing radiation source included in the radioisotope level gauge, to develop a method for accurately calibrating the radioisotope level gauge in laboratory conditions and to install the radioisotope level gauge in the preliminary channel of technological line of glass fiber production for continuous measurement of the glass mass level in online mode. The leak tightness of the Cs-137 radioactive ionizing radiation source was tested using three different methods. To calibrate the radioisotope level gauge in a laboratory conditions, a stainless steel calibration stend was used. The stand consisted of a square container with an internal lining of firebrick, and a mixture of bromoform and ethyl alcohol with a density of ρ=1799 g/dm 3 was used as a simulant liquid. A gamma source block with a Сs-137 source was installed on one side of the pre-channel, and a detector was installed on the diametrically opposite side. One external firebrick in front of the detector was removed from the pre-channel, and the resulting void was filled with fiberglass to protect the detector from heating due to the high temperature of the fiberglass. The radioisotope level gauge detector (M7213 scintillation probe, Tesakon Messele-lectronics, GmbH Dresden), which has a housing with a water cooling system and a scintillation crystal length of 35 mm (Φ=38 mm, H=38 mm), was calibrated to an acceptable glass mass level of 192.5 mm (±1 mm) from the bottom of the preliminary channel at a maximum γ-radiation flux from a Cs-137 ionizing radiation source with an intensity of 1660 pulses/sec.