Locating device - for source of strain waves eg in stressed pressure vessels

摘要

Appts. permitting location of the sources of emission of strain waves constituted by zones of very limited extent, comprises at least three detectors which can be applied against the surface of the material to be studied in defined positions and each of which incorporates (a) a transducer emitting an electrical signal the amplitude of which is a function of that of the strain waves and (b) a sequence of amplification and filtration for the electrical signal furnishing a pulse each time a threshold is exceeded, as well as means for the determination of the time intervals sepg. the appearance of a first pulse in one of those sequences from the appearance of corresponding pulses in the other sequences. More esp. means are provided for calculating the position of the source of the strain waves from the above mentioned time intervals and the position of the transducers.