压力容器垫片密封螺栓静强度安全系数的确定

摘要

Based on vague equivalent random principle in message entropy theory,taking the vague static strength and vague load being equivalent to random strength and random load for bolts with gasket sealing in pressure vessel,as per the point of view of first leakage and then explosion and the Chinese standard,author has analyzed the permissible reliability for vague static strength of bolts with gasket sealing in pressure vessel,the method was established for determining the static strength safety factor of bolts as per permissible reliability.Concerning the gasket seal construction in pressure vessel,research indicates that ：①permissible reliabilities for yield strength of bolts in case of pre-tightening,normal operation,pneumatic test and hydraulic test separately are 0.993 54,0.993 54,0.97260 and 0.7925;the permissible reliabilities for tensile strength of bolts are separately 0.999 999 991 40,0.999 999 991 40,0.999 999 991 40 and 0.999 990 226;②minimum of safety factors for yield and tensile strengths are separately 1.50 and 2.10.%基于信息熵理论中模糊等效随机的原理,将压力容器垫片密封螺栓的模糊静强度和模糊载荷等效为随机静强度和随机载荷,根据先漏后爆的观点和中国标准,分析了内压容器垫片密封螺栓模糊强度在不同工况时的许用可靠度,建立按许用可靠度确定螺栓静强度安全系数的方法。对于内压容器垫片密封结构,研究表明：①在预紧、正常操作、气压试验与液压试验时,螺栓屈服强度许用可靠度分别为0.993 54、0.993 54、0.972 60与0.792 5;螺栓抗拉强度许用可靠度分别为0.999 999 991 40、0.999 999 991 40、0.999 999 991 40与0.999 990 226;②螺栓屈服与抗拉安全系数的最小值分别为1.50与2.10。