Collection And Transmission Of Corrosion Prevention Parameters And Performance Assessment Of Corrosion Prevention In Buried Pipeline

Buried pipelines plays an important position in oil and gas industry and even in the city daily production and life.Corrosion of buried pipelines is one of the main factors leads to pipeline failure.Pipe crack or pipe perforation caused by corrosion not only affects the normal operation of the pipeline， but also cause the huge energy waste and economic losses， and may even cause Safety accident like leakage， explosion， suffocation and so on.It threats to residents’ lives and property security directly，and it can also Formate serious consequences， such as environmental pollution. Especially for those who served for a long pipeline， grasping the degree of corrosion timely， evaluatingpipeline corrosion level is an important part of ensuring pipeline safety.In this paper， we analyze the causes of corrosion and protective measures aiming atevaluating the safety level of buried pipeline corrosion protection system， minimizing the corrosion to the damage of buried pipelines and reduce the loss of state property of and eliminating the safety hidden trouble.Pipeline corrosion is due to physical and chemical factors and other factor of the environment.For example when the pipeline reacts electrochemical，chemical，microbial reactions or potential difference caused by stray current， potential difference will be formed between buried pipeline and soil，so the moving lons leads physical or chemical changes causing the accelerating corrosion speed.To solve this problem we usually use the anti-corrosion layer， the outer coating and add cathodic metheds for protection.Now mainstream solution is corrosion protection system by external coating and cathodic protection potential.In this paper， the principle and technical characteristics of various detection methods in buried pipeline corrosion protection system are anslysised and summary. Tube/potential measurement method is studied， using a pipeline of potential distribution model to locate erosion resistant coating defects according to the measured pipe-to-soil potential curve， and then voltage drop of pipe-to-soil potential measurements is discussed.Then we deliberate the principle and technical characteristics of CIPS， in order to state the relation of voltage drop， the measurements of Pearson and DCVG are expounded and proved.PCM is widely used in pipeline inspection，it can estimate the state of outside the pipe coating by calculating pipeline anticorrosion layer for insulation resistance. Measure equation of PCM is deduced， so do the Measuring steps and applicable scope. In order to control of electrochemical corrosion of buried metal pipeline in soil， the combination of external anticorrosive coating and cathodic protection protective measures is widely adopted.The outside anticorrosion layer is the main anticorrosion method， and the cathodic protection for coating defect pipe outside surface electrochemical protection is supplement of anticorrosion layer.In China， Cathodic protection potential tests of buried pipeline anticorrosive coating is still artificial point detection， which is Not only inconvenience also easy to cause the error.So GPRS module acquisition and wireless transmission system based on MCU is designed.It achieves the protection of the cathode potential and wireless transmission. In this paper， the overall design of wireless data acquisition system is introduced and the potential acquisition part， the hardware and software design of wireless transceiver part in system are descripted in detail.Measurement work of the signal shows that this system has the characteristics of high accuracy and stability，and the measured data on cathodic protection potential can be further analysised.So It has reached the expected requirements.Outer coating in service of the state to ensure the safe production and prolong the service life of buried steel pipeline is crucial. In order to grasp the performance states of buried steel pipeline outer covering layer， the status of the coating must be tested and quantized timely and we should grad evaluation of safety degree effectively.In order to analyze the service life of the protective coating， it is necessary to diagnose the failure of pipeline anti-corrosion insulation type and the degree of damage on the basis of on site inspection.However，when we evaluate the tested data， conventional methods of pipeline anticorrosive layer level evaluation often is not adaptive due to some factors affecting such characteristics as randomness， fuzziness and incompleteness.Artificial neural network has highly nonlinear mapping ability， massively parallel distributed processing and good adaptive learning mechanism， so it is suitable for solving the problems which are difficult by using the traditional pattern recognition methods.Aiming at solving the problems in the evaluation of pipeline anticorrosion layer level， the BP artificial neural network algorithm is put into use. It provides a scientific basis for management decisions and pipeline risk assessment.BP neural network algorithm is easy to fall into local extremum， and the evaluation result has a certain error. In this paper the weights of neural network is optimized by combined genetic algorithm，and then we establish genetic neural network model for buried pipeline corrosion protection system performance evaluation.Genetic algorithm is a global and robust search optimization method， it can effectively overcome the problem that neural network training process is easy to converge to local minimum. Combining genetic algorithm and neural network can make the neural network to expand the search space and improve the computational efficiency， and enhance the automation of neural network modeling. The comprehensive evaluation model uses Connection weights of neural network optimized by genetic algorithm，and it optimies the connection weights of neural network through the evolution of individual.Based on testing data，pipe material，learning environmental factors such as sample， we get more close to the pipeline operation evaluation model of the real situation. Using the evaluation model to compute the follow-up testing data， more comprehensive evaluation results of practical pipeline corrosion protection will be obtained.So this system can evaluate state of complex corrosion protection for buried pipeline in the absence of a universal clear conditions.