• Corrosion Science and Technology
• /
• v.3 no.6
• /
• pp.257-261
• /
• 2004

Leaking of fuel gas in a building creates flammable atmosphere and gives rise to explosion. Observations from accidents suggest that some explosions are caused by quantity of gas significantly less than the lower explosion limit amount required to fill the whole confined space, which might be attributed to inhomogeneous mixing of the leaked gas. The minimum amount of leaked gas for explosion is highly dependent on the degree of mixing in the building. This paper proposes a method for estimating minimum amount of flammable gas for explosion assuming Gaussian distribution of flammable gas.

• Journal of the Korean Institute of Gas
• /
• v.5 no.4 s.16
• /
• pp.62-69
• /
• 2001

Gas safety devices are very effective to prevent catastrophic gas accident in domestic. The safety devices are included in domestic gas equipment such as extinguishing safety device and adapted at pipeline such as fuse cock, shut off device with gas alarm and so forth. In spite of using those safety devices, a few hundreds of gas accident was happened annually in residential house. In this study, we analysed systematically the domestic accidents which was happened in five years using fault tree analysis(FTA) method and analysed the effectiveness of individual safety device. And also, it was suggested that the rate of accident was decreased quantitatively by increasing safety device which is adapted in domestic. By analysis of 769 gas accidents in domestic, the order of effectiveness of safety device to prevent domestic gas accident was the multi-functional gas-safe-meter(micom-meter), fuse cock, gas leak alarm and CO alarm. If the above four kind of safety device are adapted to every house, about $59\%$ of accident will be reduced and the most of catastrophic gas accident will be Prevented in domestic.

• THE INDUSTRY AND TECHNOLOGY OF GAS
• /
• v.4 no.1 s.4
• /
• pp.73-74
• /
• 2001

• YAKHAK HOEJI
• /
• v.18 no.2
• /
• pp.114-124
• /
• 1974

• Journal of the Korean Institute of Gas
• /
• v.17 no.6
• /
• pp.83-89
• /
• 2013

Energy industry facilities can cause fatal damage for internal industry employee as well as external general people because handling various kinds of gas and harmful substance might be spread to large scale severe accident by fire, explosion, and toxic gas leakage. In order to prevent these accidents, quantification by damage effect on structure and human is tried by using quantitative risk assessment, but it is difficult to process instantly exceptional cases and requires knowledge of expert. This paper aims to minimize exceptional cases and knowledge of expert, and present risk with human perceptible. So, we designed and developed zone-base risk analysis system that can compute risk of zone in real time at that point using database and incremental model.

• Journal of the Korean Institute of Gas
• /
• v.13 no.2
• /
• pp.7-13
• /
• 2009

In order to make the critical path analysis of gas pipeline located under rigid pipes for interference behavior, FE analysis is performed considering real buried conditions of a drain and a gas pipe according to intersection angle of two pipes. A drain pipe and gas pipe have cover depth respectively 1.0m and 3.39m and this study considers a interference angle in the range of $0{\sim}90^{\circ}$. In this paper, the critical path is analyzed from the result of Ring Deflection and bending stress according to intersection angle. In the event intersection angle of two pipes equal to the critical path of lower pipe. The analysis results show that the critical path of lower gas pipe according to interference behavior has relation to intersection angle of two pipes.

• Journal of Power System Engineering
• /
• v.13 no.5
• /
• pp.52-58
• /
• 2009

A gas turbine consists of an upstream compressor and a downstream turbine with a combustion chamber, and also the compressor and the turbine are generally coupled using a single shaft. Many casing bolts are used to assemble two horizontally separated casings, the gas turbine casing and the compressor casing, in both of axial and vertical directions. Because drilled holes for casing bolts in vertical direction are often too close to drilled holes for casing bolts in axial direction, one can observe cracks in the area frequently during operations of a gas turbine. In this study of the root cause analysis for the cracking initiating from the drilled holes of the casings of a gas turbine, the finite element analysis(FEA) was applied to evaluate the thermal and mechanical characteristics of the casings. By applying the field operation data recorded from combined cycle power plants for FEA, thermal and thermo-mechanical characteristics of a gas turbine are analyzed. The crack is initiated at the geometrical weak point, but it is found that the maximum stress is relieved when the same type of cracks is introduced on purpose during FEA. So, it is verified that the local fracture could be delayed by machining the same type of defects near the hole for casing flange bolts of the gas turbine, where the crack is initiated.

• Journal of the Korean Institute of Gas
• /
• v.4 no.4 s.12
• /
• pp.65-70
• /
• 2000

We develop the database program for accident cause analysis which can help to increase domestic safety custom and prevent recurrence of gas accident and analyze accidents easily The program developed in this study consists of two parts. one part uses accident case database applied if than rule, so it finds root causes by inference of some input values. The other uses Root Cause Analysis Map which divided human errors and equipment difficulties and so we get general root cause by reply some proper questions.

• Journal of the Korean Institute of Gas
• /
• v.13 no.3
• /
• pp.22-27
• /
• 2009

Recently Urban Gas Business Companies have been allowed to construct High Pressure Natural Gas pipelines, if they adopt the Risk Reduction Measures(RRMs) recommended by Korea Gas Safety Corporation(KGS) after safety assessment. This paper presents a Cost Benefit Analysis(CBA) method, when KGS performs safety assessment and recommends RRMs to Safety Appraisal Committee, to help the Committee make judgements on whether the proposed RRMs are reasonably practicable. We carried out quantitative risk assessment to high pressure natural gas pipelines as a case study and analysed cost benefit for the suggested RRMs. In conclusion, we found out the presented CBA method using PF was proper in Korea.

• Applied Biological Chemistry
• /
• v.35 no.1
• /
• pp.36-41
• /
• 1992

Several commercial cottonseed, corn and rapeseed oils were stored at $60^{\circ}C\;and\;70^{\circ}C$ with daily exposure of fluorescent light for 12 hours and evaluated their rancidity by headspace gas chromatographic analysis of pentanal and hexanal. The data of gas chromatographic analysis was compared with organoleptic flavor evaluation. For headspace gas chromatographic analysis, the volatile compounds were recovered by porous polymer trap and flushed into a fused silica capillary column at $250^{\circ}C$. Twenty-three GC peaks were identified on the basis of relative retention time of reference compounds and gas chromatography-mass spectrometry. The results showed that the contents of pentanal and hexanal were linearly increased during storage. A very simple linear relationship was found between organoleptic flavor scores and amounts of two volatile compounds with very high correlation coefficient. This results suggested the possible implication of pentanal and hexanal as an quality index for rancidity evaluation of cottonseed, corn and rapeseed oils.