METHOD AND DEVICE FOR DETECTING LEAKAGE IN PRESSURE PIPELINE Russian patent published in 2005 - IPC

FIELD: measuring engineering.

SUBSTANCE: device comprises connected in series transmitter whose control input is connected with the first output of the synchronizer and transmitting aerial, first receiving aerial, first receiver, first switch whose second input is connected with the second output of the synchronizer through a time delay unit, first multiplier, first narrow-band filter, amplitude limiter, phase detector whose second input is connected with the first output of the heterodyne, output voltmeter, comparator, second switch whose second input is connected with the output of the voltmeter, indicator, second receiving aerial, second receiver, heterodyne, first mixer, and first amplifier of intermediate frequency. The transmitting aerial has linear polarization. The first receiving aerial is sensitive to the signals with the right circular polarization, and second receiving aerial is sensitive to the signals with left circular polarization. The device is also provided with the second and third narrow-band filters, phase inverter, two adders, two 90° phase shifter, second mixer, second amplifier of the intermediate frequency, second multiplier, amplitude detector, and third switch. The output of the second receiver is in communication with the connected in series second narrow-band filter, phase inverter, first adder whose second input is connected with the output of the second receiver, second mixer whose second input is connected with the first output of heterodyne through the first 90° phase sifter, second amplifier of intermediate frequency, second 90° phase shifter, second adder whose second input is connected with the output of the first amplifier of intermediate frequency, second multiplier whose second input is connected with the output of the first adder, third narrow-band filter, amplitude detector, and third switch whose input is connected with the output of the second adder and output is connected with the second input of the first multiplier. The output of the first adder is connected with the second input of the first mixer.

EFFECT: enhanced precision and resistance to noise.

2 cl, 2 dwg