Stray current corrosion has become one of the important failure factors of buried steel pipelines. In this paper, the propagation law of stray current in soil was simulated and analyzed based on Comsol Multiphysics software, and the relationship between the decay law of stray current potential and soil resistivity was obtained. The effect of the damaged area of the anticorrosive layer, soil oxygen concentration, soil pore saturation and other factors on the pipeline ground potential at the inflow and outflow point of stray current is simulated and analyzed. The damaged area of the anticorrosive layer has a more obvious effect, the current density at the defect edge is higher than that at the center, and the outflow stray current density at the damaged point of the anticorrosive layer increases with the decrease of the damaged area of the anticorrosive layer, and the corrosion becomes more intense. Oxygen is mainly consumed at the inflow of stray current, and oxygen reduction reaction occurs. With the increase of soil porosity, the diffusion coefficient of oxygen decreases, while the conductivity of soil electrolyte increases. As the influence of soil electrolyte conductivity is larger than that of oxygen diffusion coefficient, the corrosion becomes more intense with the increase of soil porosity. The research in this paper has important guiding significance for further understanding of stray current corrosion mechanism of buried steel pipelines.
River crossing pipeline is an important part of China's oil and gas pipeline network system. For river crossing pipelines, the traditional technology of location, depth and corrosion protection layer damage detection is not suitable. Based on the investigation of the current typical river crossing pipeline inspection technology and equipment at home and abroad, this paper introduces a typical river crossing pipeline inspection equipment equipped with ROV, which is independently developed, and carries out inspection application on a domestic underwater pipeline crossing the Yangtze River. The field application results show that the ROV based detection technology of river crossing pipeline buried depth, negative protection potential and anti-corrosion layer quality is feasible, and the accuracy meets the requirements of field detection, which provides technical support and guidance for the field detection of typical river crossing pipelines in China.
Stray current corrosion is an important factor affecting the safe operation of buried steel pipelines. Aiming at the problems such as single function, low accuracy and poor usability of configuration software of existing stray current detection equipment, a stray current detection system based on STM32 and Labview for buried steel pipelines is designed, which can simultaneously measure a variety of stray current interference evaluation indexes. The system consists of two parts: acquisition system and host computer. The hardware circuit of acquisition system is designed in modular way, and the host computer is built by joint programming of Labview software and MATLAB software. The experimental results show that the measurement error of the system is less than 0.1%, which meets the standard requirements. The system has the feasibility of field application and popularization.
The DC FSM equipment used for monitoring the inner corrosion of oil and gas pipeline has problems such as low safety, vulnerable to interference and low signal-to-noise ratio. The AC FSM is developed to avoid the above problems. This paper introduce the design of data acquisition and analysis software for the AC FSM equipment, which including data preprocessing module, pipeline corrosion calculation module and data analysis and display module. The experiment showed that the software can display the internal corrosion morphology of the pipeline in the monitoring area in 3D, reflecting the internal corrosion location. The defect quantification of the software is consistent with the actual situation, indicating the effectiveness of the software.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.