• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.532-534
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• 2004

The advancement of electronics and telecommunication technologies has forced the risk management system for underground metallic structures to evolve into the remote monitoring and control system. Especially, facilities such as gas pipelines, oil pipelines and water distribution lines might make hazardous effect on human safety without continuous monitoring and control. As a result, pipeline engineers have applied cathodic protection system to prevent the degradation of their facilities by corrosion and carried out a periodic monitoring of the pipe-to-soil (P/S) potentials at numberous test boxes along their pipelines. The latter action on a road in downtowns, however, is so much dangerous that the inspectors should be ready to suffer the threatening of their lives and maintenance. In order to minimize these social costs and hazards, a stand-alone type corrosion monitoring equipment which can be installed in test box, store the P/S data for given Belied and send the data by wired/wireless telecommunications is under development. In order to obtain the exact P/S data, however, a reference electrode should be located as close to the pipeline as possible. Actually, the measured potential by a conventional portable reference electrode contain inevitably an IR drop portion caused by the current flow from the cathodic protection rectifier or the subway railroad. To minimize this error, it is recommended that the reference electrode should be buried within 10 cm from the pipeline. In this paper, we describe the design parameters for fabricating the permanent type reference electrode and the characteristics of the developed reference electrode.

• Journal of the Korean institute of surface engineering
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• v.49 no.5
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• pp.408-415
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• 2016

The offshore structures exposed to harsh corrosive such as the marine environment is essential for the quality management technique throughout the life cycle of initial design, construction and operation. Also, it should satisfy the design life and ensure the safety of the substructure with optimization of design process. This study focused on optimization of design condition for corrosion protection of wind turbine structure and computational analyzing was performed to evaluate the performance of corrosion protection with utilizing practical experimental data. We expect this analytical study contribute to improve the corrosion maintenance stability and economical efficiency of designing wind turbine structures. As a result, the design of cathodic protection system using sacrificial anodes required accurate identification of current density in order to meet the long term design life, which can be seen that a change of structure surface's coating breakdown factor is one of the key influencing factors.

• Journal of the Korean institute of surface engineering
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• v.50 no.6
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• pp.531-535
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• 2017

Enormous amount of waste oyster-shell (OS) has a major disposal problem in coastal regions. OSs have attracted much attention for recycling, because these are mainly composed of calcium carbonate with rare impurities. In this study, we demonstrate the calcareous deposit films on steel plate by using OSs on the basic of cathodic protection technique. The composition of the OSs was analyzed by wavelength dispersive X-ray fluorescence spectrometer. Carbon dioxide gas was pumped into distilled water to make carbonic acid solution for dissolution of OS. The calcareous deposit was characterized by second electron microscope (SEM), energy dispersive X-ray analysis (EDX) and X-ray diffraction. Corrosion rates were estimated by measurements of anodic polarization and immersion test. It is confirmed that calcareous deposits on steel plate are formed under all condition of cathodic protection by using waste OS from the SEM and EDX results. Calcareous deposits on steel by OS provide good corrosion resistance by acting as a barrier to oxygen supply to the steel surface.

• Proceedings of the KIEE Conference
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• 2005.10c
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• pp.273-275
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• 2005

The national need to establish a new stray current mitigation method to protect the underground metallic infrastructures in congested downtown area forced us to design and develop the distributed impressed current cathodic protection (DICCP) system. The main purpose of this system is to replace the stray current drainage bond methods, which is widely adopted by pipeline owners in Korea. Currently, forced drainage makes up about 85% of total drainage facilities installed in Korea because polarized drainage can neither drain perfectly the stray currents during normal operation of electric vehicle nor drain the reverse current during regenerative braking at all. The forced drainage, however, has been abused as an alternative cathodic protection system, which impresses currents from rails to the pipelines and accordingly uses the rails as anodes. As a result, it is necessary to consider a new method to both cathodically protect the pipelines and effectively drain the stray currents. In this paper, we describe the design parameters and installation schemes of DICCP system that can meet these demands.

• Proceedings of the KIEE Conference
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• 2000.11d
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• pp.727-728
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• 2000

The Cathodic Protection system which is usually applied to marine metallic structures in domestic is Sacrificial Anode Method. In general. low efficiency rectifiers are using in the field of Cathodic Protection. These rectifiers are not only low efficiency but also manual type which is not able to control remotely. In this paper we describe the high efficiency rectifier used the high speed switching method for optimum corrosion control of marine metallic structures.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.3130-3132
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• 2000

The Cathodic Protection system which is usually applied to marine metallic structures in domestic is Sacrificial Anode Method. In general, low efficiency rectifiers are using in the field of Cathodic Protection. These rectifiers are not only low efficiency but also manual type which is not able to control remotely. In this paper we describe the high efficiency rectifier used the high speed switching method for optimum corrosion control of marine metallic structures.

• Corrosion Science and Technology
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• v.10 no.3
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• pp.101-107
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• 2011

Marine ships have played an important role as a carrier, transporting much more than 80% of all international trading, and marine transportation is an internationally competitive, strategic, and great national important industry. However, those marine ships have the characteristics such as voyage of long distance, large-volume and lower speed than the other carry system. Therefore, it is important to manufacture a larger and faster ship, however, the steel plates which are consisted with most of those ships has brought about many corrosion problems in sea water such as general corrosion, localized corrosion, cavitation and erosion corrosion etc.. Most hulls of the ships have been protected with paintings, sacrificial anode, marine growth prevention system, and impressed current cathodic protection methods against numerious corrosion problems mentioned above. However, these conventional methods are not very effective because the rudder of ships stern are exposed to very severe corrosive environment such as tides, speeds of ships, cavitations and erosion corrosion, etc.. In this study, electrochemical and cavitation characteristics was investigated for the rudder material of ship which is exposed to serious corrosive environment. As a result, it is considered that the optimum cathodic protection potentials of rudder material is the range of -0.6 V ~ -0.8 V(Ag/AgCl) in static seawater.

• Corrosion Science and Technology
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• v.5 no.1
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• pp.5-14
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• 2006

A lot of parts in FGD (Flue Gas Desulphurization) systems of fossil-fuel power plants show the environments in which are highly changeable and extremely acidic corrosive medium according to time and locations, e.g. in duct works, coolers and re-heaters etc.. These conditions are formed when system materials are immersed in fluid that flows on them or when exhausted gas is condensed into thin layered medium to contact materials of the system walls and roofs. The environments make troublesome corrosion and air pollution problems that are occurred from the leakage of the condensed solution. The frequent shut-down and repairing works of FGD systems also demand costs and low efficiencies of those facilities. In general, high corrosion resistant materials have been used to solve this problem. However, even the super alloys and Teflon linings sometimes have not been good enough to preventing corrosion. Further more, they are expensive and not easily repairable in short periods of operation stops. In this work, new technology that is effective, economical and easily repairable has proposed to solve the corrosion problems in FGD facilities. This technology contains cathodic protection, coatings and remote monitoring-controlling systems.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.671-675
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• 2000

The purpose of this research is to evaluate the performance of various kind anticorrosives which is developed to enhance the capacity of anticorrosives in several conditions of salty reaction, and evaluate corroded state according to various amounts of chloridized material. Beside, to exam Zincspray for Cathodic Protection System evaluation.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.4
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• pp.667-674
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• 2004

This thesis is about the Impressed Current Cathodic Protection (ICCP) control and monitoring system. which brings protection against the corrosion of the ship's hull in the sea environments. The ICCP system is composed of a power supply. anode. reference electrode and controller. AC sources from the ship's generator are converted to DC sources in terms of power supply, and a protection current is sent to ship's hull though anode. The controller fully senses whether or not the detected potential is within a range of protection of ship's hull and then it is automatically controlled to increase or decrease the amount of protective current to be sent to the anode. The monitoring system with RS 232/485 communication is also studied in order to check the normal state of the system at a long period. because an operator does not always watch over this system and thus the system cannot operate well because of his or her negligent management. Since the vessel always navigates in the sea. an characteristics experiment of the ICCP system is conducted by introducing various corrosive environmental factors such as velocity, resistivity, dissolved oxygen, PH, temperature and contamination degree. These results must be referred to when the ICCP system is set up. In short. the ICCP is a multi-system for use on ships and on land structures because it includes a safety device. It is suggested that this system can accomodate a ship's automation and will be very useful.