A Sonar Detection System Based on Water Pipeline

Abstract

The invention discloses a sonar detection system based on a water pipeline. The non-contact electromagnetic angular position detection module realizes the real-time acquisition of the rotation angle position of the stepping motor, and the transducer signal line is connected through a collector ring to realize the transducer Continuous detection can be rotated in the same direction all the time to improve detection efficiency; the excitation frequency of the transducer is provided by the main control unit, that is, the excitation frequency is controllable to ensure that the excitation method is suitable for underwater acoustic transducers of different frequencies; the excitation frequency of the transducer The voltage is provided by a power module with adjustable voltage / current output, that is, the excitation voltage can be adjusted in real time, so that under various conditions of pipe diameters to be measured, the energy intensity of the primary excitation signal meets the detection requirements, and the secondary reflection signal can be accurately detected. sense and extract. The pipeline sonar detection system of the present invention is applicable to the detection scene of pipelines with water, avoids the shortcomings of conventional sonar probes, and improves the applicability and convenience of pipeline sonar equipment.

Description

technical field [0001] The invention belongs to the technical field of pipeline sonar detection, in particular to a sonar detection system based on water pipelines. Background technique [0002] In the prior art, conventional pipeline inspection methods include pipeline TV, pipeline robot, wireless periscope, etc. to detect the condition of the pipeline to be tested. These detection methods require the water level of the pipeline to be tested to be below 1 / 3 or even less; while pipeline sonar The detection method can detect the pipeline when the water level of the pipeline to be tested is high or even full. The shortcomings of the detection method improve the convenience and safety of pipeline detection. [0003] The basic principle of pipeline sonar detection is: using the sound wave reflection method, using the water body in the pipeline to be tested as the medium for sound wave propagation, transmitting an excitation signal of a specific frequency through the underwater ...

AI Technical Summary

Problems solved by technology

[0009] 1) Open-loop control: open-loop control of the stepping motor, that is, the real-time angular position cannot be known during the rotation of the motor. The absolute angle of rotation cannot even detect whether the motor is rotating, so the real-time absolute angular position of the transducer cannot be accurately known. The final sampling signal can only start from a fixed starting point when the host computer draws and displays the sampling data packet according to 360 ° Evenly divided drawing, there may be errors with the actual state and position of the defect of the object to be tested

[0010] 2) Slow refresh rate: During the detection process of the mainstream pipeline sonar probes on the market, the transducer rotates one circle from the fixed starting point to complete the detection, and then rotates in reverse to the starting point after reaching the mechanical limit point, because if it continues along the same There is a risk of breaking the signal line of the transducer if the direction is rotated, and the transducer will not be detected during the reverse rotation. This working mode prolongs the image refresh time of the host computer

[0011] 3) The excitation frequency is not adjustable: the excitation frequency of the conventional pipeline sonar probe is fixed. When the transducer is replaced, the entire hardware part needs to be redesigned, which is related to the excitation method and the filter circuit of the subsequent stage, because different Frequency transducers, the band-pass frequency range corresponding to the secondary reflection signal is also different, and the corresponding post-stage signal conditioning circuit will also be different

[0012] 4) The excitation voltage is not adjustable: for conventional pipeline sonar probes, the excitation voltage of the transducer is fixed, that is, the excitation energy is also fixed. Since the conventional pipeline sonar probes all use resonant transducers, that is, the transducers spontaneously and self-receive , which causes the secondary reflection signal to be covered by the primary excitation signal when measuring a pipe to be tested with a smaller aperture (φ6100mm), even if There is no obvious improvement by adjusting the signal gain in the post-stage signal conditioning circuit

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