風險基準檢查(RBI)是一門實務性的科學，以風險管理的角度來將石化廠的資源做更有效的分配，其中以API-581作為量化風險方法的標準，已逐漸被國內多數大型石化廠所接受，且近幾年來也有些應用的案例；在實際應用的同時，所面臨執行層面上的困難也將逐一浮現。RBI所關注之失效機率是由材料腐蝕裂化機制所引起的洩漏，且其失效機率會隨時間成長，而本文將探討在執行整廠(工場)RBI時，當多數設備沒有明顯的腐蝕劣化跡象，在某些設計條件之下(主要是由操作壓力、內徑與厚度所影響)，量化計算的結果將會與實務經驗的判斷有些差異。
此項問題目前發現是在石化產業的中下游工廠發生的機會較高，由於中下游產業的內容物較不具腐蝕性，面臨的腐蝕裂化機制較為單純，因此沒有明顯腐蝕裂化機制的設備數量將會較中上游的工廠來的多。而這類設備在進行RBI分析時，部分會因設計因素的影響，造成損傷因子(Df)的計算結果可能會高於其他需要被關注的設備，而在進行整廠性的風險評估時，會造成檢查資源分配效益不佳的情況產生，以及具有潛在風險的設備可能會被掩蓋。
根據過去實際執行的案例發現，這類的情況越來越多。本文將針對此現象，進行案例與發生原因探討，同時提出可行的解決方法供參考應用。

With more and more cases of API-581 practical applied, the problems are also emerging raise up. RBI is concerned with leaks caused by corrosion deterioration of material, and the probability of failure will grow over time. When there’s no any obvious signs of corrosion and deterioration on equipment, under some design conditions (mainly affected by operating pressure, inner diameter and thickness), the results of quantitative calculations will be somewhat different with the judgments of practical experience.
Especially in the mid-downstream petrochemical industry, the contents are less corrosive, and the corrosion mechanism is relatively simple, so the number of equipment without obvious corrosion mechanism will be more than the mid-upstream factories. However, when performing RBI analysis on such equipment without obvious signs of corrosion, partly due to design factors, the calculation result of the damage factor (Df) may be higher than that of other equipment that needs focus. In a plant risk assessment, it will lead to poor efficiency in the allocation of inspection resources. This article will discuss this phenomenon, and propose feasible solutions for reference and application.

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