• 한국가스학회:학술대회논문집
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• 한국가스학회 2001년도 추계학술발표회 논문집
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• pp.45-57
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• 2001

An alternating current (AC) corrosion using coupon has been studied. Coupons were applied in terms of AC voltage from high value to low value through the survey of AC voltages on buried gas transmission pipeline over the country. Parameters such as AC current density of coupon, AC voltage, cathodic protection potential, soil resistivity and frequency were monitored continually. Corrosion induced by AC was observed even under cathodically protected condition that met cathodic protection criterion(: below -850mv vs. CSE). Corrosion rate was affected mainly not by AC voltage but by both of frequency and AC current density. An experimental corrosion rate relationship could be obtained statistically, in which AC corrosion rate increased linearly with effective AC current density and its slope was 0.619.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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• pp.637-640
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• 2003

The owner of water pipeline has a burden of responsibility for the protection of corrosion and the prevention against leakage of water. So, they have been installed a CP(Cathodic Protection) System in oder to protect corrosion. And they also have been measured and analyzed the data about P/S(Pipe to Soil) potential of water pipeline. The P/S potential is basic data of evaluation for water pipeline corrosion. In this paper, results of development about remote wireless corrosion monitoring system for water pipe line are presented briefly.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.346-348
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• 2001

This paper analyze the interference problems, especially AC corrosion when the gas pipeline is buried with power cable in the same submarine tunnel. This paper present the results of the study about AC corrosion, limitation of safety voltage, modeling of power cables, gas pipeline and grounding systems, analysis of induction voltage according to various circumstance, soil resistivity, length of tunnel. and so on.

• 플랜트 저널
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• 제12권1호
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• pp.37-43
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• 2016

플랜트 하부 강파일 기초 주변 토양의 부식성을 평가하기 위해서 현장조사, 현장 보링작업을 통한 시료 채취 및 실험실 분석을 거친 결과를 검토하였다. 토양 분석 결과 강관파일이 타설된 토양은 여러 개의 특성이 다른 토양층으로 구성되어 있었으며, 각 지층의 화학적, 물리적 성질이 다르므로 강관파일의 타설깊이에 따른 부식성의 차이가 발생할 것을 예상할 수 있었다. 분석 결과를 토대로 정성적인 부식성 평가, 평균부식속도 및 최대부식속도를 예측한 결과, 일부 지층에서는 일반적으로 강관파일 설계시 적용되는 부식속도인 0.01-0.02mm/y 이상의 평균부식속도를 보이고 있었다 (0.33mm/y).

• Corrosion Science and Technology
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• 제7권3호
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• pp.179-181
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• 2008

With nano-$SiO_2$ and sulphate acid, a kind of colloid electrolyte is synthesized by sol-gel method. It is placed outside the reference electrode as a layer of gel electrolyte so as to decrease the leaching of $Cu^{2+}$ and increase the life of the reference electrode. The performance of the gel electrode in simulating soil solution is measured as follows: the potential of the electrodes ranging from 60 mV to 80 mV (vs. SCE) with potential variation no more than $\pm10mV$, enough resistance to polarization. The $Cu^{2+}$ effusion rate of the reference electrode without gel electrolyte is 3 times that with colloid electrolyte, which means that gel electrolyte can extend the life of the reference electrode significantly.

• Corrosion Science and Technology
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• 제8권6호
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• pp.238-242
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• 2009

Corrosion of metallic materials occurs by the reaction with corrosive environment. In general, corrosive environments are classified as atmospheric, marine, soil etc. and regardless of any corrosive environments, reduction of thickness and cracking and degradation are induced by corrosion. Among several corrosive environments, knowing the atmospheric corrosiveness of a region, city, or country is considered of ultimate importance for major industrialists and investors who require knowledge of the corrosive impact of the atmosphere on everyday materials such as carbon steel, weathering steel, zinc, copper, and aluminium. This is why the atmospheric corrosiveness map is needed. This paper dealt with corrosion properties between several waters in the region and carbon steel, weathering steel, galvanized steel, pure copper, and pure aluminium at the representative rural area of Korea - Andong.

• 한국기계가공학회지
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• 제5권4호
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• pp.33-40
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• 2006

The quality of the supply water which is supplied to consumer is not the thing of water after filtrating but the thing of water from faucet through pipe. As a result, heavy metals and microorganism, that is the major materials, which cause the distrust of the supply water is generated by supply process. Especially, the heavy metal is generated by the corrosion of waterworks. Besides, rupture by corrosion of pipe becomes the factor of supply water's pollution in waterworks and the factor of pollution of the soil and environment in drain pipe. Therefore, this research examined the weight reduction electric potential measure to measure the corrosion degree of piping materials after testing the corrosion of piping materials(Copper Pipe, Galvanized Steel Pipe, Stainless Steel Pipe) which is generally used at the moment in various corrosion environments(subterranean water, supply water, 3.5% NaCl, 3.5% $HNO_3$). And let me show basic design data about problem occurrence such as leakage water, rust water, inside and outside corrosion from this.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.104-106
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• 2004

There are many under grounds facilities like oil pipes, gas pipes, water pipes, oil tanks, etc. and severe corrosion of these facilities made big problems. Fire, wide area water and soil pollution, massive and hazardous explosion, etc. can make big problems and cause big economical loss. So, various technologies were developed to keep these undergrouns facilities safely, and cathodic protection is one of it. For cathodic protection, one must detect potential of pipes, and there are so many test box to check pipes potentials. In this thesis, we describe on the development of small size corrosion monitoring system that measure pipes potentials easily and economically.

• Corrosion Science and Technology
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• 제6권6호
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• pp.308-310
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• 2007

The owner of underground metallic structures (gas pipeline, oil pipeline, water pipeline, etc) has a burden of responsibility for the corrosion protection in order to prevent big accidents like gas explosion, soil pollution, leakage and so on. So far, Cathodic Protection(CP) technology have been implemented for protection of underground systems. The stray current from DC subway system in Korea has affected the cathodic protection (CP) design of the buried pipelines adjacent to the railroads. In this aspect, KERI has developed a various mitigation method, drainage system through steel bar under the rail, a stray current gathering mesh system, insulation method between yard and main line, distributed ICCP(Impressed Current Cathodic System), High speed response rectifier, restrictive drainage system, Boding ICCP system. We installed the mitigation system at the real field and test of its efficiency in Busan and Seoul, Korea. In this paper, the results of field test, especially, distributed ICCP are described.

• 보존과학회지
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• 제26권4호
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• pp.407-416
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• 2010

토양 중에 존재하는 철환원능력을 갖춘 세균은 철제유물의 부식생성물을 에너지원으로 이용할 수 있다. 이러한 세균의 활동은 부식생성물의 변화를 초래하여 유물의 부식을 촉진시키는 부식생성물의 판단을 어렵게 할 수 있다. 본 연구의 목적은 철환원세균이 부식생성물에 일으키는 변화를 조사하여, 철제유물의 부식에 관한 이해를 높이고자 한다. 실험은 출토철제유물을 재현하기 위해서 부식촉진인자 중에서 가용성염류(염화물이온, 황산이온)를 이용하여 부식시킨 철편을 준비하였다. 이 부식철편을 세균이 존재하는 배지에서 42일간 배양하였다. 실험 후, 부식철편의 부식생성물은 SEM, EDS, XRD를 이용하여 관찰, 분석을 실시하였다. 관찰결과, 부식철편이 세균의 활동으로 인해 녹색으로 변화하였으며 부식철편에 판상 결정과 마름모꼴 결정이 새롭게 생성된 사실을 알게 되었다.