• Journal of the korean Society of Automotive Engineers
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• v.15 no.4
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• pp.1-7
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• 1993

최근 엔진의 고성능, 고출력화, 저연비화 Maintenance Free화에 따라 엔진의 부하가 증대되었고, Valve Seat에 대해서도 내마모성, 내열성, 내식성 향상이 요구되고 있다. 특히 무연가솔린과 LPG사용으로 내구성을 갖는 High Performance의 Valve Seat 재질을 요구하게 되었고, 엔진의 높은 작동온도등 가혹한 조건하에서 'Recession'이라 일컬어지는 Seat마모가 생기게 된다. Valve Seat는 일반적으로 분말야금법에 따라 제조되고 있으며, 엔진조건에 따라 여러가지의 재질이 사용되며, 높은 온도에서 열전도성과 기공의 산화방지 및 Valve 내구성 향상의 효과를 얻기 위하여 동용침을 하여 사용하는 추세이다. 본 실험에서는 Valve Seat 기공부위의 산화와 마모특성을 조사하기로 한다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2006.05a
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• pp.129-135
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• 2006

• 한국가스학회:학술대회논문집
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• 2007.04a
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• pp.98-101
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• 2007

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.3
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• pp.42-50
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• 2001

In this paper, the effects of scale formation in engine water jacket upon the thermal durability of engine itself and its component parts were studied. To understand the effect of quality of water, a full load engine endurance test for 50 hours was carried out with not-treated underground water. The followings were found through the tested engine inspection after the endurance test; 1-2 mm thick scale formation in the engine water jacket, valve seat wear, piston top land scuffing, piston pin stick, and cylinder bore scuffing in siamese area. In order to understand the causes of above test results, the heat rejection rate to coolant, the metal surface temperature of combustion chamber, and the oil and exhaust gas temperatures were measured and analyzed. The scale formed in the engine water jacket played a role as thermal insulator. The scale formed in the engine reduced the heat rejection rate to coolant and it caused to increase the metal surface temperature. The reduced heat rejection rate to coolant increased the heat rejection rate to oil and exhaust gas and increased the oil and exhaust gas temperature. Also, the reasons of valve seat wear, piston top land scuffing and cylinder bore scuffing, and piston pin stick quantitatively analyzed in this paper.

• Journal of the Korean Institute of Gas
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• v.15 no.3
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• pp.47-52
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• 2011

The purpose of this paper analyzes and studies to seek the failure examples of electronic control actuators for engine in liquified petroleum gas vehicle. The first, it was verified phenomenon for intial starting damage and no-acceleration of engine because of occasionally fuel feeding interception by clogged of emergency cutting solenoid valve filter. The second, the contact resistance produced in the connecting part of engine control relay because of no fully surface contacting by processes and assembly badness. It was displayed phenomenon of re-starting badness. The actuator that idle speed control system was sticked inside because of intake-air decreasing by carbon deposit. As a result, it was verified the phenomenon of disharmony that repeated up and down the engine revolution.

• Journal of the Korean Institute of Gas
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• v.21 no.4
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• pp.70-75
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• 2017

This paper presents the FEM analysis results on the deformation behavior safety of automatic cut-off horizontal and conventional vertical gas valves. Based on the FEM analysis, the primary maximum deformation of $4.4{\mu}m$ was formed on the right end side of a valve body when the internal gas pressure was supplied on the screw port and gas discharge port of an automatic cut-off horizontal gas valve. And the secondary maximum deformation of $2.9{\mu}m$ was formed on the end side of safety valve port. This small deformation of an automatic cut-off horizontal gas valve is strongly related to the balanced design of a horizontal gas valve main body, which is composed of a screw part, gas outlet port, port for a stem and spindle shaft assembly, and safety valve port. But, the primary maximum deformation of 0.076mm was formed on the upper part of a conventional automatic cut-off vertical gas valve when the internal gas pressure was supplied on the screw port and gas discharge port. And the secondary maximum deformation of 0.055mm was formed on the left end side of a gas outlet port. This may effect on the sealing clearance of o-ring that is inserted on the groove of an automatic cut-off unit. Thus, this paper recommends an automatic cut-off horizontal gas valve compared with that of a conventional gas valve for a gas leakage free mechanism of a LPG cylinder valve.

• Journal of the Korean Institute of Gas
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• v.20 no.4
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• pp.25-32
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• 2016

The purpose of this study is safety evaluation of solar energy generation which is installed on the canopy at the LPG filling station. in case of a gas station, the solar energy generation was become legalization through a related law reform in 2008. Also, in case of a LPG filling station, the solar energy generation was become legalization through a related law reform in 2015. So, the related law that KGS CODE and Safety control of dangerous substances law and the case of installed solar energy generation in gas, LPG filling station was investigated. two scenarios are supposed for the CFD. Release of safety valve pipeline and ruptured dispenser leakage are the scenarios. The FLACS which developed GexCon in Norway was used for simulation. LPG dispersion to the upper side of canopy was very small with safety distance.

• Journal of Power System Engineering
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• v.19 no.4
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• pp.56-68
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• 2015

Liquefied petroleum gas and compressed natural gas haven been regarded as promising alternative fuels because of no smoke, and they are also clean fuel for spark-ignited engine. In spark-ignited direct-injection engine, direct injection technology can increase engine volumetric efficiency significantly and also reduce necessity of throttle valve. This study designed combustion chamber equipped with visualization system. To improve ignition probability, the study designed to help three types of impingement-walls to form mixture. In doing so, LPG CNG-air mixture could be easily formed after spray-wall impingement and ignition probability increased too. The results of this study could contribute as basic resources of spark-ignited direct injection LPG and CNG engine design and optimization extensively.

• Journal of Powder Materials
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• v.6 no.2
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• pp.163-170
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• 1999

Engine valve seat is a functionally important part for maintaining engine performance. The progress of automotive technology has increased the severity of conditions to which it is exposed, especially as regards LPG fuel engines and turbocharger. Therefore, it requires excellent heat and wear resistance to meet the severe condition inside the engine. In the present study, effects of solid lubricants such as CaF$_2$, MnS and MoS$_2$ on microstructure and mechanical properties of sintered Fe alloys for valve srats have been investigated for the development of valve seat material with high temerature wear resistance. As a results of engine simulation test, 0.5 wt% CaF$_2$ specimen showed the most excellent property, but in the overall aspect of view valve recession has increased with increasing the amount of solid lubricants.

• Journal of the Korean Society of Safety
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• v.21 no.1 s.73
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• pp.48-52
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• 2006

This study is a research of safety valve development for LP gas cylinder which use sintering metal. Re-searcher wishes to apply technology of sintering metal for safety valve development and do gas flow control. The basis of this study is most suitable fluid examination that to reduce gas accident. This research concluded following results. 1. When press pin length is 42mm to 45mm powder quantity is 0.25g, in case of press pin length 36mm to 42mm powder quantity is 0.2g, displayed fluid optimization. 2. When press pin length is 39mm and powder quantity is 0.25g, press pressure displayed fluid optimization at all interests from $1.2\;tons/cm^{2}\;to\;2\;tons/cm^{2}$. 3. When apparent density is about $5.0g/cm^{3}\;to\;4.5g/cm^{3}$, fluid optimization becomes.