Abstract: For random uncertainties and fuzzy uncertainty of the pressure vessel opening reinforcement，based on information entropy theory that fuzzy entropy is equal to probability entropy, the relation formula of the random variables equivalent conversion into fuzzy variables in normal distribution was established. It defined the membership function of the shell hole nominal thickness and the reinforcing pad thickness, determined the fuzziness coefficient, deduced the fuzzy reliability calculating formula of the reinforcing pad circle thickness, and illustrated calculation process.

Key words: Opening reinforcement, Information entropy, Random variables, Membership functions, Fuzzy reliability

摘要： 针对压力容器开孔补强的随机不确定性和模糊不确定性，依据信息熵理论中的模糊熵和概率熵相等的原理，建立起在正态分布下的随机变量等效转换为模糊变量的关系式，定义壳体开孔处的名义厚度和补强圈厚度的隶属函数，确定模糊性系数，推导出补强圈厚度模糊可靠性计算公式，并举例说明了计算过程。

关键词: 开孔补强, 信息熵, 随机变量, 隶属函数, 模糊可靠性