應用FMEA於緊急發電機工程施工問題預防探討

Abstract

緊急發電機為建物重要設施，具有備援能力及防災功能，為電力的備援系統，如施工不慎，導致電力中斷重要設備無法轉運，『瞬間』可能造成生命安全。因此，對於如何維持緊急發電機穩定運轉及提昇施工品質，為本研究探討的課題。藉由失效模式與效應分析方法(Failure Mode and Effects Analysis，FMEA)，本研究研討:(1)建立系統化、流程性的問題分析方法，探討在施工階段各項作業潛在問題;(2)建構緊急發電機工程之安全評估FMEA分析表，達到降低施工問題之發生，進行管控與防制對策。 為求論文之客觀性，本研究進行專家訪談及問卷調查，以機電專長為主之建設公司、設計公司、營造廠、專業廠商為對象，探討四階段(設備進場、施工圖檢討、施工查驗、系統運轉測試)施工作業及其中73項施工項目潛在的失效模式及影響效應因子與量化評估方式，評定計算相關風險值，並提出風險優先指數值排序及改善對策，提供工程人員採取事先評估預防，避免施工問題影響日後運轉測試，達到系統穩定運轉之目標，提昇施工品質，穩定建築物之備援電力為最終目的。以下為列點式說明研究成果: (1)四階段的施工作業失效風險評估： 嚴重度(S)系統運轉測試階段最為重要，因故障之風險最高，須重視及檢討作業程序。 發生率(O)施工圖檢討階段是發生問題較多的部分，須特別關注施工圖套繪作業。 檢知度(D)系統運轉測試階段的複雜性及專業性較高檢核不易，應加強教育訓練。 整體風險指數(RPN)以系統運轉測試階段所佔之比重最高，再者為施工檢查階段，其他次之。 (2)風險評估部份： 嚴重度(S)的施工風險是中高度的風險值。 發生率(O)的施工問題是偏低，表示緊急發電機工程的施工問題已普遍性降低了。 檢知度(D)的施工項目大部分是有經驗及一定層度的了解。 (3)藉由FMEA以系統化及流程性的方法建構四階段緊急發電機工程FMEA作業流程及實施步驟，以供後續機電工程人員參考應用。 (4)運用FMEA以專家訪談及問卷調查探討73項作業項目，並研擬失效模式與效應分析計算出RPN值及改善對策。 (5)運用失效模式與效應分析法FMEA作為施工評析工具，可因應各種不同建案條件或施工經驗作為機電工程評估工程風險及預防施工問題之方法，後續他案重要施工管理檢討依據，以降低重要工程的施工問題產生。

Emergency generators are important building facilities, with backup capabilities and disaster prevention function as the power redundant system. If the construction accidentally causes power outages, the important equipments cannot function and the specific “instant” may even cost human life. Therefore, the study investigated how to maintain the stable emergency generators operation and enhance the quality of construction. By using Failure Mode and Effects Analysis (FMEA), the study include: (1) Establish the systematic problem analysis methods to investigate the potential problems during the emergency generator construction phase.(2) Generate the FMEA analysis table to assess the emergency generator construction safety and consequently reduce the construction issues for future control and prevention. The questionnaire is created to assure the objectivity of the study. The target interviewees of this survey include construction companies, design companies, and professional manufacturers; all of which are specialized in mechanical and electrical systems. It’s emphasized on four phases (site access, construction drawing review, construction inspection, and operation system test) and 73 construction tasks within four phases in finding potential failure modes, factors and quantitative assessment methods. Then, it is used to evaluate the risks associated with the calculated values, sort the risk priority number and propose improvement measures. Hopefully, it may provide engineers with proactive prevention assessment, avoid the construction issues affecting the followed operation test, stabilize the operation system, improve construction quality, and eventually reach the ultimate goal- stabilize buildings redundant power system. In summary, the study findings include: (1) Four phases of construction operations failure risk assessment: Severity (S): The operation system test phase is the most important. The risk is the highest with the breakdown system. Therefore, the operating procedures must be reviewed thoroughly. Occurrence (O): The problems are most frequently occurred during construction drawing review phase. It’s needed to pay special attention to construction shop drawing. Detection (D): The operation system test phase is complex and highly specialized. It should be focus on education and training in this phase. Risk Priority Number (RPN): The RPN of the Operation system test is the highest. The second highest is the construction inspection phase. (2) Risk assessment: Severity (S): The risk level of construction is moderate to high. Occurrence (O): The occurrence of the construction issues is low, which means that emergency generators problem has been reduced in general. Detection (D): Most of the responses show that they are experienced in construction tasks and have certain degree of knowledge. (3) By systematic FMEA method, the guideline of the emergency generator construction including standard operating procedure and implementation procedures in four phases is created for electrical engineering staff. (4) Based on the expert interviews and the questionnaire, FMEA is used to investigate 73 tasks, develop Failure Modes and Effects Analysis, calculate RPN value and propose the improvement measures. (5) Failure Modes and Effects Analysis (FMEA) can be used as a construction assessment tool in response to a variety of different building conditions or construction experience. FMEA can also be used as a method to evaluate the construction risk for mechanical and electrical system. Besides, it can also be used as the basis for construction management to reduce the potential construction problems in critical tasks.