• Journal of Advanced Marine Engineering and Technology
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• v.35 no.4
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• pp.443-450
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• 2011

Fuel gas compressor system is applied to medium FPSO. In order to avoid surge, this system used the anti-surge valves. When surge occurs it may lead to system's fracture. So anti-surge valves are evaluated structural strength and structural safety. Especially, in emergency mode, valves are must be guaranteed structural safety. In this study, structural strength and structural safety of anti-surge valve was evaluated using the numerical simulation. Unigraphics NX 4.0 was used as Geometrical models, structural strength and structural safety calculation were carried out by ANSYS Workbench 12.1. The ASME Boiler & Pressure Vessel Code is refer to allowable strength and safety factor of the valves.

• Journal of the Korean Institute of Gas
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• v.22 no.4
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• pp.74-81
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• 2018

The Korean Government has proceeded petroleum gas pipeline construction business since 2014 for rural districts. The operating pressure of petroleum gas pipeline are from 25kPa to 75kPa which are different from that of natural gas pipeline. Petroleum gas pipeline pressure is ten or forty times higher than natural gas operating pressure. For this reason, petroleum gas pipeline has higher probability of accident occurrence from massive gas leakage. Korea Gas Safety Corporation begins to development excess flow valves and their performance testing equipment since 2017. The excess flow valves stop the gas flow when a overflow happened in gas pipeline. The excess flow valves are generally not installed in main pipeline, because that may block massive gas supply. So, the valves are installed in starting points of branch pipes. According to the number of house and amount of gas use, a shut-off point of exxcess flow valve is determined called as Trip Flow. The trip point is the most important thing of excess flow valve, so, it is required a equipment testing the performances of excess flow valve as trip point.

• Journal of the Korean Institute of Gas
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• v.11 no.1 s.34
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• pp.34-39
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• 2007

In this paper, the FEM result has been presented for a sealing safety between a valve packing and a valve seat during a open and close operation in a LPG cylinder. The sealing operation of a LPG valve is completed when the valve packing in which is made by a nylon-66 polymer is to stop a LP gas flow, which flows out from the outlet of a brass pipe in a LPG cylinder. The contact sealing mechanism of the valve may be classified by a flat contact of an unused valve packing and a circular groove contact of an used valve packing in a current LPG valve. Based on the FEM and experimental investigations the sealing force, 4.9 MPa for a flat contact mode of the unused valve packing is a little high compared to that of the used valve packing, which shows a circular groove contact geometry against a valve seat. But these sealing pressures for two contact modes are very low compared to the ultimate strenath 83 MPa of the nylon-66 and this may be designed with a excess strength of the valve.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.05a
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• pp.675-678
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• 2003

현대 사회에서 가스 산업은 기반 기순 산업으로 영향력이 매우 커지고 있으며, 동시에 위험요소를 내포하고 있다. 본 논문은 가스밸브의 연결부분에서 폭발성 발화물질인 오일성분에 의한 안전사고를 방지하고자 유지분 검출시스템을 개발하였다. 용기 밸브의 영상을 $200{\times}200$ 크기의 흑백 이미지로 획득하고, 제안한 유지분 검출 알고리즘을 적용한다. 먼저, 영상에 소벨(Sobel) 연산자를 이용하여 에지(Edge)를 검출하고 오일이 존재하는 영상과 오일이 존재하지 않는 영상을 영상프로파일(image profile) 분석과 영상 감법 둥의 검출방법으로 비교 분석하였다. 첫 번째 방법은 영상프로파일기법으로 3가지 영역인 부분영역, 하위영역, 전체영역으로 오일을 삽입한 후 다항식 근사로 오일의 존재여부를 판별하였고, 두 번째는 영상감법으로 밸브의 특정한 위치에 위치조정표시를 한 후 두 영상의 차를 구하였다. 실험에서는 제안한 검출방법의 실용화 가능성을 확인하였다.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.6 no.3
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• pp.156-161
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• 2013

Gas valve time control system used to set the time to use the gas system by one of the user's negligence explosion, fire, and to prevent accidents such as suffocation. Gas valve is one of the items is not a replacement without any special issue after installation in each customer. So sufficient test is required prior to the installation device. In this study, the test system was developed to use to set the number of times at the gas valve time control system.

• Journal of the korean Society of Automotive Engineers
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• v.14 no.1
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• pp.47-53
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• 1992

대도시의 자동차 배기가스에 의한 대기오염문제는 날로 심화되어 가고 있으며, 그 규제 역시 매 우 엄격해지고 있다. 배기가스의 문제는 연소실내에서의 고효율연소에 의해 개선될 수 있으며, 이 를 위해서는 혼합가스 생성장치에서의 잘 미립화된 혼합가스의 생성에 관한 미시적 연구가 필수 적이다. 본 연구에서는 범용 유체 유동해석, 프로그램을 이용하여 Butterfly밸브 주위에서의 공기 의 흐름현상을 예측하였으며, 밸브의 손실계수(Kv)를 실험치와 비교하여 보았다. 또한 압축성과 비압축성 유체 유동해석의 비교, Residual Mass(R. M)의 최적치 정의에 의한 CPU 시간의 최소 화, Numerical Grid Size의 해석결과에 미치는 영향 등에 관해 알아보았다.

• 기계와재료
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• v.22 no.1
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• pp.54-64
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• 2010

공작기계의 고속화, 다축화, 복잡화에 따른 열변형 오차가 공작기계에서 발생하는 오차의 대부분을 차지하고 있다. 이러한 열변형 오차를 최소화 하기 위해 공작기계의 발열부에 차가운 오일을 공급하여 냉각함으로써, 열변형을 제거하는 장치가 오일쿨러이다. 오일쿨러는 제어 방법에 따라 On-off, 가스 바이패스, 인버터 방식 등이 사용된다. 초정밀 공작기계에는 주로 가스 바이패스 및 인버터 방식이 사용되는데, 인버터 방식의 경우 고가(高價)인 관계로 주로 옵션 형태로 사용된다. 가스 바이패스 방식 오일쿨러는 인버터 방식에 비해 가격이 저렴하고 구조가 간다하며 정밀한 온도제어를 할 수 있지만 부하가 낮은 경우 구조적인 한계로 인해 온도제어 불안정을 발생시킨다. 본 연구에서는 기존 바이패스 방식 오일쿨러에서 나타나는 문제점을 해결하고 보다 정밀한 온도제어를 위해 2개의 전자밸브를 갖는 듀얼 밸브 방식 오일쿨러 시스템을 개발하였다. 개발된 듀얼 밸브 오일쿨러 시스템의 성능검증을 위해 정격운전, DIN 8602 규격, ISO/DIS 230-3 운전모드에서 성능을 비교/분석하였다.

• 한국가스학회:학술대회논문집
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• 2006.11a
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• pp.49-54
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• 2006

• Journal of the Korean Institute of Gas
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• v.21 no.5
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• pp.9-15
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• 2017

Natural gas fuel has known to be very promising in terms of abundancy and economic value. Therefore it is widely treated as research topics in a variety field of production, storage and utilization. Natural gas has become one of the major sources for the power generation by using internal combustion engines(ICE). Development of natural gas fuel injection device should be preceded to realize a reliable natural gas fuel supply system for a MW class power generation reciprocating ICE. In this research, an injection valve which consists of solenoid and body part with a moving plate was designed and its dynamic performance was experimented in the engine-like environment. Displacement length and diameter of an armature and diameter of a solenoid coil were tested at former study. In this research the effect of materials of solenoid core, size of main housing inlet and supply gas pressure are examined.

• Journal of the Korean Society of Propulsion Engineers
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• v.13 no.6
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• pp.48-55
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• 2009

The purpose of using Gas Generator Oxidizer On/Off Valve(GOV) is to control opening and closing of oxidizer mass flow. This paper describes analytical results of flow and structural properties for four different GOV models, using commercial software such as Fluent(Ver. 6.3.26) and NASTRAN(2005 r.2), PATRAN(2005 r.2). Analytical results show that GOVs could generate 2.3~3.8 kg/s of oxidizer mass flow rate and come up with 1.09~1.42 of safety factor.