• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.11a
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• pp.243-250
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• 2000

배관을 지하에 매설할 경우 매설배관이 묻히는 깊은 도랑을 트랜치라 하는데 이 트랜치의 폭과 깊이의 칫수를 적절하게 결정하는 것은 매설배관의 건전성을 유지하는데 중요한 인자중의 하나이다. Watkins는 매설배관의 트랜치 폭에 대한 연구를 수행하여 최근 그 결과를 발표한바 있다. (1) Fig. 1에 트랜치와 배관의 단면도를 그리고 일반적으로 사용하는 기술적인 용어를 나타내었다.(중략)

• Journal of the Korean Institute of Gas
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• v.18 no.5
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• pp.12-19
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• 2014

To minimize the risk of corrosion on buried pipeline and to maximize the efficiency of cathodic protection, various indirect inspection techniques have been used for decades. In the United States, 49 CFR has regulated the external corrosion direct assessment for buried pipelines. In Korea, there is no provision for external corrosion direct assessment but there is only, according to the KGS Code, provision that if the survey of the defects of buried pipeline and the leakage test for the pipe were conducted, it is deemed to leakage inspection. We, therefore, have suggested external corrosion direct assessment method appropriate to domestic status through the survey of the regulations and standards of UK and the USA and the investigation of domestic situation on coating damage detection method. The proposed external corrosion direct evaluation method was used as the basis when introducing the precision safety diagnosis regulation for the medium-pressure pipe in Korea.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1999.05a
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• pp.38-38
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• 1999

매설배관은 도로 혹은 철길올 횡단하는 경우와 같이 굴착에 의한 시공이 불가능한 경우에 압업관을 사용하여 시공하며 이러한 압업관은 배관이 토양의 하중으로부터 안 전하게 유지되도록 하는 기능도 한다. 압엽관은 배관과 접촉이 되지 않도록 절연체 를 배관과의 사이에 삽업올 하도록 규정되어 있는데 여러 가지 이유로 배관과 접촉이 되기도 한디 배관과 압업관이 전기적으로 접촉되면 배관을 방식하기 위한 방식전류 를 압입관에 빼앗기게 되고 압업관 내부의 배관은 비방식 상태에 놓이게 되어 부석이 일어날 가능성이 높다. 본 연구는 실제 매설배관 현장에서 배관과 압입관의 접촉여부 에 대하여 조사한 방법 및 결과에 대한 것이다. 본 연구에서는 압업관의 접촉여부를 확인하기 위하여 다음과 같은 방법을 사용하 였다. 첫째. 배관과 압입관의 방식선위를 단순하게 측정하는 것이다. 배관과 압업관 의 전위가 같은가 다른가를 측정하는 방법이다. 둘째, 배관의 방식전류를 on, off하면서 배관과 압입판의 전위거동을 살펴보는 것이다. 셋째, 배관과 압업관을 언위적으로 접촉시켜 흐르는 전류량을 확인함으로써 접촉여부를 확인할 수 있었다. 넷째 배관을 따라 흐르는 방삭전류량을 측정하였다. 이상과 같은 방법을 사용하여 배판과 접촉된 압압관을 확인할 수 있었다. 접촉된 압입관에서 접촉지점을 확인하기 위하여 배관과 압입관 사이에 전류를 인가하고 압입 관의 양단의 배판 사이의 전위 변화를 측정하여 그 전위변화값과 인가한 전류값을 통 하여 계산된 저항올 배관의 길이로 환산하여 대략적인 접촉지점을 확인할 수 있었다.

• Journal of the Korean Institute of Gas
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• v.21 no.6
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• pp.30-38
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• 2017

Established in the 1960s, high pressure underground pipelines in Ulsan and Yeosu industrial estate are underground as toxic gas as well as combustible gas that is heavier than city gas and low combustion range. Especially, industrial pipelines occupy more than 20 years old pipes. In this way, the industrial estate pipeline was installed before the introduction of the supervision of construction, However, unlike the city gas pipeline, the pipeline is managed without any legal obligation. In this study, the safety management status of high pressure underground pipelines and urban gas underground pipelines in the industrial estate is analyzed and comparison of laws, extent of damage impact, using the pipe inspection model for pipe inspection of high pressure piping system with the existing piping system. it is intended to cuntribute to improving the safety of industrial estate are underground pipeline.

• Journal of the Korean Institute of Gas
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• v.22 no.5
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• pp.100-106
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• 2018

pressure buried pipes in domestic industrial estate have many long-term use pipes, Toxic, flammable, Inflammable, etc. as well as a variety of toxic chemicals are embedded in a complex be buried, A high level of safety management is required as it can damage other pipes installed nearby in the event of accidents such as various external interference. Therefore, in this study, the safety management practices of high-pressure gas distribution and urban gas distribution are utilized to derive efficient safety management methods for high-pressure gas installation piping through in-depth comparative analysis.

• Journal of the Earthquake Engineering Society of Korea
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• v.11 no.6
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• pp.41-52
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• 2007

Earthquake time-history analyses have been carried out for a buried gas pipeline of X65 which is of popular use in Korea. Parameters included are shape of a buried gas pipeline, soil characteristics, single and multiple earthquake input ground motions and burial depths. Predicted response of strain and relative displacement are then compared with allowable strain and displacement capacity calculated by Guidelines for the Seismic Design of Buried Gas Pipelines, KOGAS. Comparative studies show that strains are in general affected by the burial depths together with change of soil conditions. Regarding the relative displacement, while axial relative displacement is not influenced by the burial depths, transverse relative displacement is affected by both burial depths as well as soil conditions. In all, the current study is encouraged to give a useful information for healthy earthquake evaluation of a buried pipeline.

• Journal of the Korean Institute of Gas
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• v.14 no.6
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• pp.51-56
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• 2010

Records of accidents for buried pipeline across the river were gathered and causes were analysed. The results are intended to be utilized as basic data for determining a reasonable criteria for the depth of buried city gas pipeline crossing the river. Accident of river-crossing buried pipeline was mainly caused by flood. Sometimes corrosion was detected at the failed location of the pipe. In order to determine reasonable and efficient depth of burial of the pipeline, hydraulic evaluation of the river and structural analysis of the pipeline are necessary. Published data for the buried natural gas pipeline incidents were also investigated and summarized. Main causes of buried natural gas pipeline incidents were external interference and corrosion. However, the two main causes of incidents showed significant difference in the proportion of the entire incident, depending on burial environment.

• Journal of the Korean Institute of Gas
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• v.27 no.4
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• pp.19-26
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• 2023

Earthquakes are one of the most important disasters affecting underground structures. Urban gas underground pipes may cause safety problems of structures in the event of an earthquake. Since Korea began digital observation, the number of earthquakes has been steadily increasing. The seismic design standard for urban gas pipes was established in 2008, but it is difficult to estimate the impact of pipes in the event of an earthquake based on the installation of pipes. In this study, structural analysis was performed on PE (polyethylene pipe) pipes and PLP (polyethylene coated steel pipe) pipes, which are mainly used as buried pipes in Korea, according to environmental and pipe variables in the event of an earthquake. This study sought to find the variables of the most vulnerable buried pipe by modeling pipes through Computer Aided Engineering (CAE) and generating displacement on the ground. Through this study, it was confirmed that the larger the elastic modulus of the soil, the deeper the buried depth, the smaller the tube diameter, and the higher the pressure, the more PLP pipes are affected by earthquakes than PE. Based on these results, the vulnerable points of buried urban gas pipes are inferred and used for special inspections of buried pipes in the event of an earthquake.

• The Journal of the Acoustical Society of Korea
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• v.31 no.7
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• pp.449-460
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• 2012

The importance of the leak detection of a buried pipe in a power plant of Korea is being emphasized as the buried pipes of a power plant are more than 20 years old. The objective of this work is to enhance the capability of the leak detection technique in a noisy environment. For this purpose, a modified cross-correlation method that can effectively remove the rotating machinery noise component is suggested. In addition, a method for leak point detection using phase information of cross-spectrum is suggested. The validity of the proposed method is verified by performing an experiment. The experimental result demonstrates that the performance of the cross-correlation method can be enhanced by reducing the periodic noise components due to mechanical equipment.

• Journal of the Korean Institute of Gas
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• v.13 no.2
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• pp.30-35
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• 2009

The result of this research explains an interactive behavior of buried steel pipe located below hume pipe using concept of effective depth and effective length against their intersection angle and burial distance. The cover depth of upper rigid (hume) pipe is 1.0m and depth range of flexible (steel) pipe is 0.5m to 5m from beneath bottom of hume pipe. And one more variable is their intersection angle in this study, it was considered from $0^{\circ}$ to $90^{\circ}$. From the results of this study, the effective depth is proportionally increasing with its intersection angle and decreasing with distance increment between two pipes. Finally, the relationship between effective length and summation of occurred bending stress is defined.