Multi-channel data acquisition device for submarine pipeline magnetic flux leakage internal detector

Abstract

The invention discloses a multi-channel data acquisition device for a submarine pipeline magnetic flux leakage internal detector. The multi-channel data acquisition device comprises a hall sensor, a multi-path switch, an instrument amplifier, an analog-to-digital (AD) conversion module, a field programmable gate array (FPGA), a digital signal processor (DSP) and a secure digital memory (SD) card, wherein the multi-path switch has a two-stage series structure; the multi-channel data acquisition device is provided with heat insulation cotton so as to adapt to a specific high-temperature and high-corrosion environment of a submarine pipeline; the hall sensor converts the magnetic induction density into voltage; the voltage is switched by the multi-path switch, so that a signal is transmitted to the instrument amplifier; the instrument amplifier amplifies a weak signal; the AD conversion module sets sampling for eight times through software, performs analog-to-digital conversion, and transmits a digital value to the FPGA after the conversion; and the DSP receives FPGA cached data, digitally filters and compresses the cached data, and finally stores the data into the SD card. Due to a dual central processing unit (CPU) structure consisting of the FPGA and the DSP, a large amount of data can be stored and processed; the device has the characteristics of high speed, multiple channels, high resolution and the like; furthermore, pipeline transportation safety is guaranteed; and early maintenance is facilitated.

Description

technical field [0001] The invention belongs to the technical field of industrial automation control, and in particular relates to a multi-channel data acquisition device for a magnetic flux leakage internal detector of a submarine pipeline. Background technique [0002] Pipeline non-destructive testing technology is a technology used to detect safety hazards such as corrosion, wear, and cracks in long-distance oil and gas pipelines in the petroleum industry. The detection of the pipeline mainly includes the internal detection and external detection of the pipeline. [0003] At present, the external inspection of the pipeline can prompt when the pipeline has leaked, but this is an after-event treatment, which can only reduce the loss, and cannot completely eliminate the loss. However, the internal inspection of pipelines can identify potential pipeline defects, and can distinguish the size and type of defects for early maintenance, so that they can be found and repaired bef...

AI Technical Summary

Problems solved by technology

[0004] The existing technology is basically a device for detecting defects in land pipelines, and it is impossible to find a device specifically for detecting defects in ocean pipelines

Seawater corrodes the pipeline severely, and extreme weather such as ocean storms increases the residual stress of the pipeline. These factors lead to a large difference in the life prediction and safety assessment methods and technologies of the pipeline compared with land pipelines. The existing safety assessment methods for land pipelines are not suitable for ocean pipelines.

[0005] In the existing magnetic flux leakage detection device, from the perspective of system structure, the output of the AD conversion unit is connected to the computer processing system, and the computer processing system performs final processing on the signal, and the application environment determines that the magnetic flux leakage detector needs to be on the seabed for a long time Walking in the pipeline, so it must be separated from the PC, and the data can only be processed by the microcontroller; from the point of view of the data acquisition method, it mainly directly applies the plug-in data acquisition card based on the ISA and PCI bus, which has the following defects: the installation is cumbersome, Expensive, poor scalability, unable to do electromagnetic shielding, resulting in data distortion

For example, the clock frequency of the single-chip microcomputer is low, which seriously affects the speed of the entire system, especially the data acquisition task of multi-channel high-frequency switching.

At present, similar products at home and abroad have not provided corresponding solutions for the harsh working conditions of high temperature and strong corrosion on the seabed

Images