國內外壓力容器規範之比較及適用性研究

壓力容器之構造安全必須遵循相關規範之規定，各國政府依照各該地域與需求訂定或採用相關安全規範，以保障容器之使用安全，然而，隨著國際化、全球化之趨勢，直接引用國外安全構造規範所製造之設備，輸入我國境內使用時，其是否滿足我國者之安全標準規定，實有研究之必要。本文係將我國CNS 9788及其相關標準，國內較常見之他國壓力容器安全構造規範，針對通則與設計板厚部份進行比較分析，文中所比較之他國規範含日本之JIS B 8265及JISB 8266、英國PD 5500以及美國ASME Sec. VⅢ, Div. 1等。就通則而言，由於地域性，或多或少各有不同之特色處，然而就適用範疇而言，他國之標準規範與我國者，已有相當之差異，本文除歸納分析外，並以簡單之壓力適用範疇，說明其壓力之適用範圍。除此之外，本文也針對各規範之規定板厚、及最小板厚等，詳細以相同之設計條件，逐一以實際計算分析、比較，並以CNS之第1種容器為比較基準，結果顯示，各規範之規定除了圓筒形胴體之板厚與CNS之規定者相近外，其餘之球形胴體板厚，及各型端版之基本厚度，均依規範之種類、壓力等級等之不同，而有相當之差異，依本文所定義之差異率正負符號，可以清楚地釐清相對於CNS第1種容器所規定之厚度差異。由本文之分析及歸納顯示，應無法建立出一所謂的「規範等效通則」，反而應在採用不同規範前，單獨針對擬遵循之壓力容器規範，詳細比對與檢討，且至少必須以「不小於CNS壓力容器規範之規定」為原則，否則無法滿足替容器之安全把關之目的。

關鍵字

壓力容器規範；規範比較；構造安全標準

並列摘要

It is well known that in order to maintain the minimum safety, the construction of pressure vessels shall comply with the corresponding codes or standards. As a consequence, the individual organizations or governments all draw up their own construction codes so that the regional characteristics can be included to the codes. Thus, along with the trend of globalization, pressure equipment that complies with a foreign code and is directly imported and operated within Taiwan is inevitable. However, whether the equipment can fulfill the requirement of the local safety standard is then vital to the domestic industries. The present report compares a few commonly seen pressure vessel codes, based on the local CNS 9788 and related standards. These codes include JIS B 8265 and B 8266, ASME Sec. Ⅷ, Div. 1, and British PD 5500 that is later generalized as the code for the whole European Community. Based on the comparative results, the deviations can be clearly observed even in the general construction rules. The reason of these deviations may mainly attribute to the regional needs or individualities. However, the differences of applicable pressure ranges can be clearly identified among the codes. And the variation in pressure ranges for these codes is plotted as a quick guild in the present report. In addition, the minimum required thicknesses of shell and end plates are also analyzed and compared with the local code-the first class pressure vessels of CNS. The results reveal that the required thicknesses of cylindrical shells are all similar. On the other hand, the required thickness of spherical shells or any type of end plates deviates quite severe. The deviations are pressure dependent and can be identified by the sign of the deviation index, which is defined in the present paper. As conclusions of the present report, the authors would not recommend the so-called equivalence of codes, nor directly apply any foreign codes without further detail study or analyses. More than that, the constructional safety less than that of CNS can never be allowed. Otherwise, the least standard of safety can never be achieved.

並列關鍵字

Pressure vessel codes ； Comparisons of codes ； Constructional safety of pressure vessels

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