FIELD: nuclear power plants; checking pipelines and reactor equipment for tightness. SUBSTANCE: proposed device designed for acoustic diagnosing of industrial installations consists of high-temperature capacitive sensor rated for up to +300C. Sensor is connected with matching amplifier by special heat-resistant cable two solid shields. Sensors and cable are protected from moisture and high level of radiation. Sensor with measuring devices is matched with charge amplifier and then signal is supplied through normalizing voltage amplifier to microprocessor or central minicomputer. Blowhole flow of steam-water mixture getting out from worn out pipelines is used as parameter under checking. Defect is presented in form of pulse harmonic components differing in amplitudes and phases with values of acoustic noise and its spectrum characteristics being chosen as parameters to be checked. Methods of evaluation of thermal noises on capacitive sensor and input resistance at sensor output are determined. Expression for evaluation of noises and interference caused by different sources is found. Methods of discriminating of useful signal disguised noise and interference are proposed. EFFECT: enlarged sphere of application, improved reliability. 2 dwg
Authors
Dates
2002-05-10—Published
2000-07-27—Filed