Hardware Design And Implementation Of Underwater Pipeline Coating Detector

With the rapid development of Chinese economy, oil and natural gas consumption is increasing. As a major means of transportation of oil and gas, pipeline transport develops rapidly. Because a large number of pipelines cross rivers, the safety of underwater pipeline draws more and more attention. To coat anticorrosive layer on the outer wall of underwater pipeline, is the main pipeline anticorrosion measure. Once the pipeline anticorrosive layer is broken, the effect of cathodic protection on pipeline will reduce greatly, at the same time, since the pipeline is under water, the speed of pipeline corrosion will accelerate. Once the pipeline corrosion occurs, it will lead to oil and gas leakage. The leakage of oil and gas will cause huge economic losses and serious environmental damage. Once the pipeline explosion happens, this will cause irreparable personal safety accidents. In view of this, the detection technology of underwater pipeline anticorrosion coatings is very important.This paper studies the detection technology of pipeline anticorrosion at home and abroad. Basing on those studies, this paper uses many electric current method in charge of frequently(PCM) to design the detector of underwater pipeline anticorrosion coatings.Specific work of the design are as follows:1) Specific design of AC signal generator. Firstly, this paper makes a hardware circuit design. This design chooses a scheme of linear power supply and switch power supply based on the electronic characteristics of oil and gas pipeline. During the design process, this paper makes a theoretical circuit simulation include linear constant current source simulation and switching power supply simulation. Secondly, This paper does such works as actual circuit board design, PCB soldering, and hardware debugging. The generator consists of digital circuit and power circuit.The former’s function is generating AC reference signal, and the laster’s function is voltage-current conversion and improving the power.2) Specific design of magnetic receiver. The receiver consists of pipeline detector and magnetic data analysis module. The pipeline detector is a special high permeability magnetic induction coil. The magnetic data analysis module selects ARM and FPGA chips. There are three functions in this FPGA chip: sampling magnetic signal, filtering digital signal, and sending the digital signal to ARM chip. There are many functions of ARM, such as human computer interaction, converting the data from FPGA intopipeline information, and storing the information in real time. The magnetic data analysis module’s hardware circuits include digital circuit and analog circuit. The digital circuit’s functions are four parts: amplifying the weak signal of magnetic filed, RF filtering, power interference filtering(Wave trap), and high-frequency interference filtering(Low-Pass filter). The digital circuit’s functions are as follows: sampling the magnetic signal by the analog circuit, exacting the digital information, sending the information to ARM, and ARM convert the information into pipeline informations such as the location of pipeline, the current on the pipeline, and the pipeline anticorrosion coatings. At the same time, ARM display the information on LCD and store the information into U disk.3) carrying out laboratory test and field test on the detector of underwater pipeline anticorrosion coatings, to verify the reliability of the instrument.