Corrosion control in pipeline due to stray current of high voltage systems

摘要

Stray currents can impact the ability to protect a pipeline or other buried metallic structure from corrosion. They can be generated from a variety of manmade and natural sources. Common sources of stray currents are cathodic protection on other lines, DC transit systems and telluric activity. The electrochemical mechanism of aqueous corrosion is outlined and it is demonstrated that the process depends upon acomplex interaction between the material and its environment given the particular circumstances of exposure. Failure to recognize the full implications of the environment or the circumstances will often lead to unexpected corrosion failure. The techniques for controlling corrosion are sub-divided into the detect the stray current of electrical discharge using optical method which implement inside the lab. Electrical Discharge (ED) is a term used to describe electrical discharge activity which is normally accompanied by sparks. ED can occur when electric field difference across the void exceeds the minimum breakdown field strength. Therefore, ED measurement and diagnosis is an important nondestructive technique for assessing the quality and integrity of high voltage transformer. In practice, ED measurements suffer from noise interference due to low sensitivity of available sensors. Sensors usually pick up noise from the environment. Noisy signal at the output of the sensors cause inaccuracy in the detection of ED. In this study, Fibre Optic Sensor (FOS) was used because of two main factorsanalyzing results of ED signal generated patterns appear to be associated with discharge show more accuracy. The technique could be used as a predictive technique to check the progression of ED, and hence keep the pipeline under constant supervision into prevent the corrosion.