An Array of Multielectrodes for Locating, Visualizing, and Quantifying Stray Current Corrosion

CORROSION ◽  
10.5006/2828 ◽  
2018 ◽  
Vol 74 (10) ◽  
pp. 1093-1101 ◽  
Author(s):  
Ke Wang ◽  
Facundo Bob Varela ◽  
Mike Yongjun Tan
Keyword(s):  
Cathodic Protection ◽  
Laboratory Simulation ◽  
Buried Pipeline ◽  
Stray Current ◽  
Simulation Experiments ◽  
Corrosion Rates ◽  
Pipeline Corrosion ◽  
Probe Array

An array of multielectrode corrosion probes, designed based on a series of coupled wire beam electrodes (WBEs), has been devised as a new tool for locating, visualizing, and quantifying the effects of stray currents on buried pipeline corrosion. It has been demonstrated in laboratory simulation experiments that this WBE probe array is capable of detecting stray current corrosion affected sites along a pipeline, visualizing stray current corrosion patterns and corrosion rates, and evaluating the efficiency of cathodic protection against stray current corrosion. Based on these results, two applications of this WBE probe array have been proposed for stray current corrosion survey and monitoring.

scholarly journals Study on Distribution Characteristics of Metro Stray Current and Evaluation of Cumulative Corrosion Effect

2022 ◽  
Vol 2022 ◽  
pp. 1-12
Author(s):  
Shan Lin ◽  
Jing Zhang ◽  
Xuehua Liu ◽  
Xianwei Zhang ◽  
Zhichao Cai ◽  
...  
Keyword(s):  
Finite Element ◽  
Current Distribution ◽  
Element Model ◽  
Distribution Model ◽  
Distribution Characteristics ◽  
Buried Pipeline ◽  
Stray Current ◽  
Power Sources ◽  
Quantitative Calculation ◽  
Pipeline Corrosion

Stray current directly affects the regular operation of electrical equipment and facilities in the subway DC traction power supply system. Therefore, it is worthwhile to study the stray current distribution characteristics during train operation and the quantitative corrosion of buried pipelines. This paper introduces the traction characteristics of power carriages and power wheelsets of subway vehicles into the DC traction process. A finite element model considering the dynamic distribution of stray current under the actual operation of subway vehicles is established. The interference characteristics of stray current and the contribution of power sources under the multiparticle model are analyzed. The rail insulation damage caused by long service time and the quantitative calculation of rail and buried pipeline corrosion is considered. The model results show that the stray current in the buried pipeline under the multiparticle model is more accurate and more suitable for the protection in the actual subway. The quantitative corrosion of the buried pipeline is stronger than the partial insulation damage environment when the rail is not insulated. The rail and buried pipeline corrosion at both ends of the insulation damage position is relatively severe. The stray current distribution model established in this paper gives full play to the solution advantages of the finite element method and provides a new idea for the quantitative calculation of buried pipeline corrosion.

Study of Effect and Protection for Corrosion on Buried Pipeline by AC Interference

2012 ◽  
Vol 557-559 ◽  
pp. 1756-1763
Author(s):  
Li Jing Zhang ◽  
Yi Wei Pan ◽  
Gang Tao ◽  
Yi Min Wang ◽  
Yuan Li
Keyword(s):  
Corrosion Rate ◽  
Acid Soils ◽  
Corrosion Products ◽  
Specimen Surface ◽  
Small Scale ◽  
Alkaline Soils ◽  
Buried Pipeline ◽  
Stray Current ◽  
Ac Interference ◽  
Pipeline Corrosion

Small-scale experiments were conducted to evaluate the corrosion on buried pipeline by AC interference. The results showed that stray current, pH and conductivity are significantly influenced the pipeline corrosion rate according to the response surface methodology (RSM) . The corrosion rate of buried pipeline greatly increased with the increase of stray current. The corrosion rate of most specimens first decreased and then increased slightly with the rise of pH. The corrosion rate of most specimens first decreased and then increased with the rise of conductivity in acid soils, but contrary in neutral and alkaline soils. Most of the specimen surface was covered with different sizes of reddish-brown bumps corrosion products in the acidic solution and reddish-brown, black corrosion products in the alkaline solution, but the specimen surface was smooth in the neutral solution. Because of economic and environmental factors, the AC interference is not always achievable. Therefore, comprehensive approaches should be taken for AC interference protection.

Coatings Formed on Steel by Cathodic Protection And Their Evaluation by Polarization Measurements

CORROSION ◽  
1963 ◽  
Vol 19 (2) ◽  
pp. 59t-68t ◽  
Author(s):  
W. J. SCHWERDTFEGER ◽  
RAUL J. MANUELE
Keyword(s):  
Weight Loss ◽  
Cathodic Protection ◽  
Protective Coatings ◽  
Salt Water ◽  
The Other ◽  
Carbon Anode ◽  
Zinc Anode ◽  
The Third ◽  
Corrosion Rates ◽  
City Water

Abstract Three steel specimens were continuously exposed in the laboratory for almost 5 years in city water to which was added 3 percent by weight of sodium chloride. Two of these specimens were under continuous cathodic protection, one by current from a zinc anode, and the other by current from a rectifier through a carbon anode. The third specimen was left to corrode freely. As a result of the cathodic protection, carbonates and silicates formed protective coatings which eventually reduced the current density required for protection from about 5 to 0.02 ma/sq ft. A coated specimen, after being without protective current for 32 days (including 12 days out of the salt water), required only 0.3 ma/sq ft for initial protection. The instantaneous corrosion rates on the coated specimens (scratched and unscratched) while without protective currents were measured by changes-in-slope (breaks) in polarization curves. The currents at which breaks occurred in the cathodic curves were found to be related to ΔV/ΔI values from the curves, which values in turn bore a relation to the corrosion rates as measured by weight loss.

Integrity Challenges Associated with Stray Current Corrosion Across Monolithic IJ's and Resolutions

2021 ◽  
Author(s):  
Ebrahim Salem Al Salemi ◽  
Saleh Salem Al Ameri ◽  
Ajiv Mohan Nair ◽  
Humaid Musabah Al Ali ◽  
Mario Jr Javier Zantua ◽  
...  
Keyword(s):  
Cathodic Protection ◽  
Ionic Current ◽  
Low Carbon Steel ◽  
Internal Surface ◽  
Low Carbon ◽  
Stray Current ◽  
Gas Industry ◽  
Factors Affecting ◽  
Steel Material ◽  
Internal Lining

Abstract Corrosion and subsequent failures is one of the main factors affecting uninterrupted operations of Oil & Gas Industries. Pipelines are considered as most convenient means of crude and gas transportation in Oil & Gas Industry. Buried pipelines generally made of low carbon steel material are protected externally by coating and applying impressed current cathodic protection (ICCP). Monitoring and maintaining adequate level of Cathodic Protection (CP) for such pipelines remains challenging for corrosion engineers due to increased level of field congestion, complexity in accurate current mapping and mitigation of corrosion phenomena. Failure of pipelines due to corrosion can be catastrophic with following consequences: Loss of containment fluid and thereby probable fatalityDamage to asset/company reputationSafety and Environment (Fire, Toxic gases and Oil Spill)Resource and downtime cost impact Isolation joints IJ's are designed with very high insulating material at mating areas and installed on pipelines by welding to avoid loss of Cathodic Protection (CP) current. Due to high electrical insulation, a potential difference is formed across of IJ's due to applied CP current and stray currents. In upstream Oil & Gas Industry, multiphase crude transported via pipeline will have certain percentage of water and will induce an internal conductive path across the IJs resulting in ionic current discharge at anodic areas within internal surface. This study focuses on factors contributing to such internal stray current corrosion, limitation in monitoring methodology and mitigation programs. The study concludes with recommendations such as design modifications, improvement in internal lining properties and improved installation guidelines. The study practically illustrates effectiveness of combined resistive bonding and zinc earthing cells installation for controlling stray current propagation in order to reduce the corrosion rate so as to maintain Integrity of pipelines.

scholarly journals Untangling the formation and liberation of water in the lunar regolith

2019 ◽  
Vol 116 (23) ◽  
pp. 11165-11170 ◽  
Author(s):  
Cheng Zhu ◽  
Parker B. Crandall ◽  
Jeffrey J. Gillis-Davis ◽  
Hope A. Ishii ◽  
John P. Bradley ◽  
...  
Keyword(s):  
Solar Wind ◽  
Hydroxyl Radicals ◽  
Laboratory Experiments ◽  
Synergistic Effects ◽  
Lunar Regolith ◽  
Laboratory Simulation ◽  
The Moon ◽  
Imaging Studies ◽  
Simulation Experiments ◽  
Proton Implantation

The source of water (H2O) and hydroxyl radicals (OH), identified on the lunar surface, represents a fundamental, unsolved puzzle. The interaction of solar-wind protons with silicates and oxides has been proposed as a key mechanism, but laboratory experiments yield conflicting results that suggest that proton implantation alone is insufficient to generate and liberate water. Here, we demonstrate in laboratory simulation experiments combined with imaging studies that water can be efficiently generated and released through rapid energetic heating like micrometeorite impacts into anhydrous silicates implanted with solar-wind protons. These synergistic effects of solar-wind protons and micrometeorites liberate water at mineral temperatures from 10 to 300 K via vesicles, thus providing evidence of a key mechanism to synthesize water in silicates and advancing our understanding on the origin of water as detected on the Moon and other airless bodies in our solar system such as Mercury and asteroids.

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