• Journal of the Korean Institute of Gas
• /
• v.22 no.6
• /
• pp.28-33
• /
• 2018

Currently, the government has been expanding the supply of semi-low-pressure in order to solve the problems of unsupplied area of city gas and to secure the economical efficiency of small supplied area. It is mainly supplied from the central storage tank to each household by buried piping. It is necessary to provide such a shutoff valve that can block the excess flow gas due to pipeline leak or rupture when piping is damaged by other construction. For this study, System CFD code named Flownex has been used and a component corresponding to the actual EFV was developed. We compared Flownex results with experimental data to verify the accuracy of Flownex and confirmed the error rate to be around 2%. In this study, pipeline network modeling was done by selecting the LPG supply pipeline in a village and installed the component of the EFV at each junction. We selected the longest pipeline from the main pipeline and set scenarios so that the excess flow occurs by that the pipeline is ruptured before entering the household. The excess flow occurs by the pipeline rupture and the EFV is closed. At this time, we analyzed backflow effects to the other pipeline by closing EFV.

• Journal of the Society of Disaster Information
• /
• v.18 no.3
• /
• pp.646-659
• /
• 2022

Purpose: In this study, we developed a 4-way sway prevention brace that efficiently reduces the installation area and has excellent stability and seismic performance compared to the conventionl sway prevention brace used in existing firefighting facilities. The performance and reliability of the developed 4-way way prevention brace were analyzed by the tensile, compression tests and seismic tests. Method: As the static test, 4-way sway prevention braces were installed on the horizontal and vertical pipes to perform the tensile and compression tests based on the KFI certification standard and the maximum movement was measured at the rated load. As a dynamic test, 4-way sway prevention braces were installed in the pipes filled with water, and the test response spectrum to the input excitation wave were measured through the acceleration sensors. After the seismic tests, separation, failure, and local deformation of the pipes, and 4-way sway prevention braces were not observed. Result: The results of the tensile and compression tests indicated that the maximum movement of the pipe during tension and compression was 50% to 70% or less compared to the certification values, indicating that the performances of the 4-way sway prevention braces were very excellent. The results of the the seismic tests indicated that the test response spectrum of the 4-way sway prevention braces is within the required response spectrum. Conclusion: In this study, it was found that the 4-way sway prevention braces satisfied the KFI certification standard and were superior compared to the existing sway prevention brace in terms of the stability, cost, and installation area.

• Journal of the Society of Naval Architects of Korea
• /
• v.53 no.5
• /
• pp.428-434
• /
• 2016

A lot of drawings for pipe construction and installation are needed to construct plant process system on the offshore plant structures. Depending on their scale or complexity, the required number of drawings related pipes sometimes amounts to several hundreds of thousands. Most major shipyards, therefore, have their own system which can automatically depict pipes’ geometric, manufacturing, and BOM(Bill of Material) information on the drawings. However, as the complexity and absolute quantity in the isometric region on the drawings is increased, the information extraction from the customized DB and positioning at the typical locations does not get to be enough to avoid the overlap between geometric contours, labels, and symbols. For this reason, the novel methods to arrange additional annotations without overlaps are presented in the paper. This approach is expected to increase the readability and legibility of the drawing and prevent the human error, and finally decrease the time-consuming and tedious jobs which are unnecessarily required to designers.

• Journal of the Society of Naval Architects of Korea
• /
• v.56 no.2
• /
• pp.152-160
• /
• 2019

In this study, we propose a piping material supply management method using CAD system. The piping materials installed in super large offshore plants have very complicated connection conditions. Therefore, it is very difficult to determine the order of receipt of a large number of installation materials. Therefore, we have developed a system that can automatically check the preparation rate of installation materials prior to the installation process. We have developed an algorithm to obtain connection information among installation items from PDMS system. We have developed an algorithm that can determine the order of installation materials to be installed using the connection information. The order of the installation material is determined by taking into account the constraint conditions for the complete installation of the piping material. We confirm the effectiveness of the developed algorithms in the operating system. This system is also used to manage installation schedules and plan the installation manpower.

• Journal of the Korean Institute of Gas
• /
• v.20 no.4
• /
• pp.50-57
• /
• 2016

According to the urban gas business legislation, cathodic protection systems should be applied for buried steel gas pipelines to prevent corrosion. In advanced countries including United States, the criteria for Cathodic Protection Potential is at least -850mV with respect to a saturated copper/copper sulfate electrode(CSE) when the CP applied, and the IR drops must be considered for valid interpretation. However, the IR drop through the pipe to soil boundary has been neglected in Korea. According to KGS code, a reference electrode must be placed in proximity to gas pipelines possible when measuring the CP potential. In this study, we have installed several solid reference electrodes around the buried pipeline(1.2m depth), lower surface(0.5m depth), and the surface individually in order to measure the CP potentials through the each reference electrode and find out the IR drops according to the location of each reference electrode. We have found the IR drop is the greatest when measuring the CP potential through the electrode placed on the ground and the IR drop is the smallest through the electrode installed near pipeline. Therefore, we have suggested the solid reference electrode should be installed as close as possible to buried pipeline in order to measure the correct CP potential without IR drop. We have also suggested the amendment of CP criteria considering IR drop.

• Proceedings of the Korean Nuclear Society Conference
• /
• 1998.05b
• /
• pp.897-902
• /
• 1998

국내 경수로 원자력발전소 가압기는 안전성향상을 위하여 보다 많은 배관과 부수적인 배관이 설치 될 수 있다. 이에 따라 ASME 코드의 공식에 의한 설계(Design by Formula)보다는 해석에 의한 설계 (Design by Analysis)의 필요성이 증가하고 있다. 본 논문에서는 한국 표준형 원자로의 가압기 헤드 및 노즐에 대하여 ASME 코드의 해석에 의한 설계를 적용하여 범용유한요소 코드인 IDEAS로 응력해석 하고 구조적 건전성을 분석, 고찰하였다. 또한 해석결과에 따른 가압기헤드, 노즐 그리고 노즐보강에 대한 설계시 고려되어야 할 인자를 분석하였다.

• Proceedings of the Korean Institute of Industrial Safety Conference
• /
• 1998.05a
• /
• pp.131-135
• /
• 1998

사용이 편리하고 깨끗한 에너지에 내한 선호도가 증가하면서 가스의 보급이 금속히 확대되었을 뿐만 아니라 향후에도 지속적인 증가 추세를 보일 것으로 보인다. 특히 연탄ㆍ유류ㆍLP가스의 사용이 감소하면서 도시가스의 보급률은 전체 수용가구가 '98년에 624만 7천 가구로 49.2％의 전국 보급률을 갖고 있다. 또한 배관의 총 길이는 15,357km로 과거 5년 전 보다 2배정도 증가하였으며 시설 또한 증가 추세이다. 따라서 도시 가스를 각 가정, 사업장 등에 공급하기 위한 배관의 설치를 산업의 발달로 지하공간을 이용한 공사가 점차적으로 확산되고 있다. (중략)

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.05a
• /
• pp.79-79
• /
• 2004

벨로우즈는 형상자체가 가지는 유연성으로 인하여 배관시스템에서 발생하는 변형을 흡수하여 시스템의 파손을 방지하기 위해 주로 사용한다. 특히 자동차, 항공기, 선박의 파이프 배관시스템 설계시 열, 고압에 의한 변형 방지, 배기계의 진동 흡수 등을 위해 가장 널리 사용되고 있다. 또한 벨로우즈는 파이프라인에는 모든 경우에 사용이 가능하고, 설치와 유지보수가 간단하다는 이점이 있다.(중략)

• Proceedings of the Korean Institute of Industrial Safety Conference
• /
• 2001.11a
• /
• pp.281-286
• /
• 2001

우리나라는 석유가 나지 않는 비산유국으로서 거의 모든 에너지 자원을 막대한 외화를 지급하여 수입하고 있는 실정이다. 이렇게 수입되는 에너지원중에서 대기 오염 등의 환경문제가 대두되면서 액화 천연가스가 청정에너지로 두각을 나타내게 되었으며, 국내에서는 도시가스로 보급되어 수요가 점차적으로 계속 증가하고 있는 추세이다 기체상태로 기화된 천연가스는 일반 가정이나 산업체에 관로(pipe line)를 통하여 공급되는데, 이들 가스배관은 대부분 지하에 일정한 깊이로 매몰되어 설치된다.(중략)

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
• /
• v.32 no.10
• /
• pp.31-35
• /
• 2003

배수설비시스템에 적용되는 각종 기기들의 특징 및 통기관의 선정 방법을 미국의 ASPE code에 제시되어 있는 내용을 중심으로 소개하고자 한다. 건물 내에서 발생하는 오수 및 배수는 항상 건물 외부로 잘 배출시켜야 한다. 이러한 배수시스템은 원활한 배수가 수행되어야 하도록 수평배수관은 적합한 구배를 주어야 하며, 부지경계선 밖에 설치된 공공하수도와 체결하여 한다. 오수배관은 지상에 노출시키거나 사설정화조를 체류하지 않고 우수로에 직접 배출할 수 없다. 배수설비를 설계할 때의 문제점은, 배수배관 및 통기관을 선정시 선정된 관경이 최적화되었는지 평가하는데 있다. 즉, 현존하는 건축물의 배수시스템에서 문제점이 발생하지 않는다고 설계된 배수배관경 및 통기관경이 최적화된 것으로 평가하기에는 어려움이 있다고 판단된다.(중략)