• 한국전산유체공학회지
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• 제21권4호
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• pp.54-60
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• 2016

The valve used in nuclear power plant must be qualified but the limitation of the test facility leads to use the numerical analysis. The flow coefficient is calculated with the consideration of the pressure, velocity and geometry. And the flow coefficient is the important physical property which is prepared using experiment or analysis by valve manufacturer. In this study, the analysis model was made according to ISA 75.02.01 and the mass flow rate and pressure drop ratio was calculated. The model of the expansion factor was applied to the simulation result and the pressure drop ratio at the start of the choked flow in the valve was found. With the simulation result, the consideration was performed that the expansion factor is the important physical property to the system engineer in addition to the flow coefficient.

• 비파괴검사학회지
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• 제30권2호
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• pp.110-115
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• 2010

발전용 밸브 내부의 누설은 냉각 기능 상실 및 방사선물질 방출 동 안전계통의 성능 저하와 수많은 에너지 손실 등 발전소 운전에 막대한 손상 및 사고를 초래하게 된다. 본 논문은 신뢰성 높은 진단 방법 개발을 위하여 국내 원자력발전소 2차계통의 누설 발생 또는 내부 부품의 손상이 발생할 수 있는 밸브를 대상으로 현장시험 및 모의누설실험시의 적외선열화상 측정 실험을 수행함으로써 단일계측방식의 불확실성을 제거하고 향후 누설진단에 대한 확대 적용을 도모하고자 하였다. 발전소 현장시험 및 밸브 모의누설시험시의 밸브 누설 상태에 따른 적외선열화상 이미지 측정 실험을 통하여, 적외선열화상 측정 방법은 밸브 누설 상태의 과정을 신속하고 정밀하게 측정 가능하며 향후 많은 종류의 밸브 누설진단에 활용함으로써 누설에 따른 막대한 에너지 손실 및 사고 예방의 유용한 기법으로 확대 적용이 가능할 것으로 생각된다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.251-251
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• 2000

Tangjin Power Plant is modern Korean standard plant which is made up Once Through Super Critical Boiler, Turbin, Generator and Flue Gas Desulfarization System. INFI-90 system fur control of the 500 MW Korean standard super critical once through boiler Mark-V for Turbine, EX-2000 fer Generator, WDPF for FGD were installed in Tangiin thermal power plant. There were two BFPTs, BFPM, 25% control valve, 35% control valve to control boiler feed water flow. It is very difficult to tune the Separator Tank level control system and change the mode from Wet to Dry. This paper focuses on test results and modification control logic for feed water control system in Tangjin power plant.

• 동력기계공학회지
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• 제11권3호
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• pp.35-40
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• 2007

Leak would happen because of the damage of high temperature and high-pressure valve in nuclear power plant. condition based prevention maintenance is essential by using the suitable method based on local condition. Energy loss prevention can prevent from an accurate test, Local actually and ability. The methods of test for high energy fluid leak at present are analysis of ${\Delta}T$, AE(Acoustic Emission) analysis, and thermal image. The result for test of secondary system in nuclear power plant Unit reveals that the AE occurred clearly in leakage situation, but thermal image didn't occur. It is identified that leak is occurred when the orifice located front and back of valve operates. It shows that making a impatient judgment by using the single method if it is leakage is containing uncertainty. So we think that using the Multi-Measuring method is more sound judgment than single-measuring method.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.138-144
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• 2000

원자력발전소 분기관에 설치되어 있는 6" swing check valve 중 일부에서 seat 면이 다소 손상되어 O/H 기간중에 시트면 연마정비 또는 밸브 교체정비를 수행하였다. 본 논문에서는 실험적 및 이론적 연구를 통하여 밸브 시트면 손상 원인을 분석하였으며, 분석 결과 구조공진 및 음향공진의 복합적인 작용에 의한 밸브 chattering이 손상 원인임을 규명하였다.

• 한국생산제조학회지
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• 제19권4호
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• pp.548-552
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• 2010

The air suction filter of the power plant decrease the dust and impurities of suction air that reduce the life and efficiency of the boiler. The suction efficiency of the air filter falls with the dust and impurities when the time of use comes to be long. Therefore, the various contaminant of the filter must remove periodically. This paper presents a developed quick exhaust valve to use in the thermo-electric power plant. to removing contaminants on the filter, the blowing is done shortly by air pressure. The Air flowed out to the out side from the inside of the filter. The performance test of the developed valve is done by making a test-bench according to JIS and KS standards. The efficiency is found higher than the existing related valve.

• 한국압력기기공학회 논문집
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• 제19권1호
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• pp.52-59
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• 2023

The welding part of the valve needs immediate action when leakage occurs due to cracks or damage. In order to repair leakage of the welding part, the valve must be separated from the pipe or replaced with a new valve. However, it is difficult to remove the valve while operating the power plant. This study presents a method to remove leakage by precisely processing the gap between the clamp and the incision part within 0.1mm while installed in the pipe system. If the external leakage is removed using a clamp on the welding part without removing the valve during operation, the time and cost required for maintenance can be reduced.

• 비파괴검사학회지
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• 제28권4호
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• pp.315-322
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• 2008

발전소 밸브는 장시간 동안 고온고압하의 기혹한 조건으로 운전됨에 따라 밸브 시트(seat)면의 이물질 삽입, 시트의 균열, 스템(stem) 패킹(parking) 또는 용접부위 결함 및 피로균열 둥에 의해 누설손상이 발생하고 있다. 이러한 밸브 내부누설 상태를 정밀하게 진단하고 평가하기 위해서는 음향방출기술의 적용이 필요하며, 본 논문은 현장적용이 가능한 연구를 수행하고 그 결과를 소개하고자 한다. 또한 실제 발전소에서 운전되는 다양한 밸브 조건을 토대로 실험실 실험에 의해 주변잡음, 밸브누설시의 음향레벨 및 스펙트럼 특성을 분석하고, 발전소 현장실험 결과와의 비교분석을 통하여, 밸브 누설상태에 따른 주변잡음, 음향신호 및 측정 가능한 최소 누설검출량 등의 평가방법에 대해 고찰하였다. 실험실 실험 및 현장적용 연구결과로부터 밸브누설 여부를 포함한 상태 평가와 최소 측정가능 누설검출량 평가가 가능하였으며, 향후 본 연구는 발전설비 안전운전과 밸브누설로 인한 에너지 손실 예방에 크게 기여할 것으로 기대된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.537-541
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• 2002

This paper is about the development of the turbine valve actuator efficiency analysis system for the standard power plants. We developed hydraulic power unit and turbine valve actuator controller. We designed control algorithm for turbine valve actuator, implemented and verified it at the industrial plants.

• International Journal of Safety
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• 제11권2호
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• pp.10-14
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• 2012

Recently, the combined power plants are refocused rapidly as a replaceable energy system of the nuclear power plant. The large turbine is revolved highly at 1800~3600 rpm. Thus, the turbine speed should be monitored with mechanical and electrical method for a safety. The electrical cutoff valve which blocks the flow channel with the electrical signal is with a built in. The aim of this study is to develop a manufacturing technology through by the localization of a solenoid actuated directional control valve. Especially the results show performances of the solenoid valve by the experiments and modeling and the reliability estimation. Applied load port pressure was changed rapidly on the form of a quadratic curve over time. And in the cases of square waveform when 0~100 V and 20~120 V input voltage, it was driven on a stable state until 13.4 Hz and 16.6 Hz, respectively. We think that this study will give useful data for the electricity safety system of the combined power plant gas turbine.