• 대한안전경영과학회지
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• 제9권1호
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• pp.65-76
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• 2007

The likelihood of failure for the stress corrosion cracking (SCC) of caustic cracking, which affect to a risk of facilities, was analyzed through the risk based-inspection using API-581 BRD. We found that SCC of the caustic cracking was occurred above 5 % NaOH concentration, and the technical module subfactor (TMSF) was maximized for above 50 % concentration. The heat traced and monitoring were not sensitive to the TMSF with NaOH concentration and temperature. But the steam out was more of less affect minimum value of the TMSF. Also, the inspection number, the inspection effectiveness, and the year since inspection were very sensitive to the TMSF with NaOH concentration and temperature. Therefore, the plan of next inspection will be established with compositively considering those at once.

• 한국가스학회지
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• 제14권4호
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• pp.37-44
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• 2010

본 연구에서는 압력설비의 위험 원인분석 방법을 제시하기 위하여 API-581 절차에 의한 위험기반검사(RBI)에서 염산부식의 두께감소로 인한 사고발생 가능성을 해석하였다. 이를 위해 사고발생 가능성의 주요 인자인 기술종속계수(TMSF)를 산출하고, TMSF에 미치는 매개변수의 영향을 정량적으로 해석하였다. 그 결과, TMSF는 염화이온 농도와 온도가 증가할수록 증가하였으나, 설비두께, 검사횟수 및 검사유효성이 증가할수록 감소하였으며, 모니터링이 있는 경우와 과설계계수가 1.5배 이상인 경우에는 상당히 적은 값을 나타내었다. 이때, 검사횟수, 검사유효성 등급 및 과설계 계수의 크기에 따라 TMSF가 민감하게 변화하였으며, 모니터링은 TMSF의 크기만 변화시켰다.

• 대한안전경영과학회지
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• 제8권2호
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• pp.61-70
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• 2006

The likelihood of failure by the corrosion of high temperature $H_2S/H_2$, which affect to a risk of facilities, was analyzed through the risk based-inspection using API-581 BRD. We found that the corrosion rate was increased as temperature and $H_2S$ concentration were increased. Also, the technical module subfactor(TMSF) was increased as an used you increased, material thickness decreased, inspection number decreased, and inspection effectiveness increased. In these conditions, the maximum value of TMSF was not varied, but the TMSF was sensitively varied at low temperature for high concentration of $H_2S$.

• 대한안전경영과학회지
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• 제7권4호
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• pp.101-110
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• 2005

The likelihood of failure for the thinning of high temperature sulfide and naphthenic acid corrosion, which affect to a risk of facilities, was analyzed through the risk based inspection using API-581 BRD. We found that the corrosion rate was increased with increasing temperature and total acid number(TAN). And maximum value of the technical module subfactor(TMSF) was not varied with operating condition, but the TMSF was sensitively changed at the range of low temperature, low flow rate, and high TAN. Also, the TMSF was increased as an used year and inspection effectiveness increased, but it was increased as thickness, inspection number, and over design decreased.

• 한국가스학회지
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• 제10권1호
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• pp.1-6
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• 2006

압력설비를 안전하고 효율적으로 사용하기 위하여 본 연구에서는 API-581 절차에 의한 위험기반검사에서 취성파괴에 의한 사고발생 가능성을 정량적으로 해석하였다. 그 결과, 낮은 온도/낮은 인성파괴와 뜨임취성에서는 A 충격곡선이고. 낮은 온도와 열처리 전인 상태에서 기술종속계수(TMSF)가 큰 값을 나타내었고, $855^{\circ}F$ 취성에서는 위험도가 무시할 수 있었으나, 시그마상 취성에서는 낮은 온도의 고 시그마인 경우에 TMSF가 큰 값을 나타내어 사고발생 가능성이 매우 높았다.

• 대한안전경영과학회지
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• 제6권3호
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• pp.99-107
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• 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

• 대한안전경영과학회지
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• 제6권4호
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• pp.239-248
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• 2004

Likelihood of failure for the external corrosion of carbon and low alloy steels, 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. In this condition, the TMSF showed high value for the case of the marine/cooling tower drift area as a corrosion driver, poor quality of coating, no insulation, and low insulation condition.