• Title/Summary/Keyword: likelihood of failure (LOF)

Search Result 4, Processing Time 0.016 seconds

Analysis of Likelihood of Failure for the Brittle Fracture through Quantitative Risk Based Inspection using API-581 (API-581에 의한 정량적 위험기반검사에서 취성파괴에 의한 사고발생 가능성 해석)

  • Kim Tae-Ok;Lee Hern-Chang;Jang Seo-Il
    • Journal of the Korean Institute of Gas
    • /
    • v.10 no.1 s.30
    • /
    • pp.1-6
    • /
    • 2006
  • To use pressurized facilities safely and effectively, a likelihood of failure (LOF) for the brittle fracture was analyzed quantitatively through the risk based inspection using API-581 BRD. We found that for the case of the low temperature/low toughness and the temper embrittlement, the technical module subfactor (TMSF) showed high value for the A impact curve, low temperature, and the no post weld heat treatment. But the risk didn't significantly change at the $855^{\circ}F$ embrittlement, and the LOF far the sigma phase embrittlement showed high value at low temperature of the high sigma.

  • PDF

- Analysis of Likelihood of Failure for the External Corrosion of Stainless Steel through the Quantitative Risk Based Inspection Using API-581 - (API-581에 의한 정량적 위험기반검사에서 스테인리스강의 외부부식에 의한 사고발생 가능성 해석)

  • Lee Hern Chang;Kim Hwan Joo;Kim Tae Ok
    • Journal of the Korea Safety Management & Science
    • /
    • v.6 no.3
    • /
    • pp.99-107
    • /
    • 2004
  • Likelihood of failure (LOF) for the external corrosion of stainless steel, which affect to a risk of facilities, was analyzed quantitatively through the risk based inspection using API-581 BRD. We found that the technical module subfactor (TMSF) decreased as the inspection number increased and it increased as the inspection effectiveness and the used year increased, and that the TMSF showed high value for the case of the marine/cooling tower drift area as a corrosion driver, In this condition, the LOF for the external corrosion of stainless steel had lower than that for the carbon and low alloy steels

Reduction Method for the Risk of the Chemical Facilities by KS-RBI Program Supporting the Quantitative Cause Analysis (정량적 원인분석이 가능한 위험기반검사(KS-RBI)에 의한 화학설비의 위험도 경감방안)

  • Kim, Tae-Ok;Lee, Hern-Chang;Jo, Ji-Hoon;Kim, Kyu-Jung;Kwon, Hyuck-Myun
    • Journal of the Korean Institute of Gas
    • /
    • v.12 no.2
    • /
    • pp.110-117
    • /
    • 2008
  • The risks of the chemical facilities were estimated by the KS-RBI(Ver. 3.0) program supporting the quantitative cause analysis, and reduction method for the risks of the facilities was investigated. As a result, we could find that the risks of the facilities decrease with reducing the likelihood of failure (LOF) affected by demage mechanism, inspection number and effectiveness of inspection, and with reducing the consequence of failure (COF) affected by the ratings of the detection, isolation, and mitigation systems. Furthermore, high risks of the facilities would be decreased by reduction of the LOF and the COF simultaneously. Accordingly, the applied plant would be able to achieve the decrease of inspection and labor costs because of the decrease of consequences and inspection intervals through the reduction of risks.

  • PDF

Analysis of Likelihood of Failure for the Thinning of Hydrochloric Acid Corrosion through Risk-Based Inspection using API-581 BRD (API-581 절차에 의한 위험기반검사에서 염산부식의 두께감소에 의한 사고발생 가능성 해석)

  • Lee, Hern-Chang;Jo, Ji-Hoon;Shin, Dong-Il;Kim, Tae-Ok
    • Journal of the Korean Institute of Gas
    • /
    • v.14 no.4
    • /
    • pp.37-44
    • /
    • 2010
  • To propose a cause analysis method of pressurized facilities, a likelihood of failure (LOF) for the thinning module by hydrochloric acid corrosion was analyzed through the risk-based inspection (RBI) using API-581 BRD. For this investigation, the technical module subfactor (TMSF), as a main factor of the LOF, was estimated, and the effects of parameters on the TMSF were analyzed quantitatively. As a result, we found that the TMSF increased with increasing chloride ion concentration and temperature, but it decreased with increasing thickness of the facilities, inspection number and inspection effectiveness. Also, the TMSF showed a relatively low value for the monitoring system implemented and the overdesign factor>1.5. In this condition, the TMSF changed sensitively with the inspection number, the inspection effectiveness and the overdesign factor, and its magnitude varied with the monitoring system.