Strength Analysis And Safety Evaluation Of Pressure Vessel

With the development of modern industry, pressure vessel is widely used inelectric power, petroleum chemical industry, light industry, textile industry,metallurgy, mechanical industry and medicine industry. With its wide application,pressure vessel development toward large-scale, complexity and strict conditions.More and more power strength and the complex structure pressure vessel are put intooperation, but due to design pressure increasing, high strength steel and weldingtechnology has widely been used, pressure vessel inevitably contain some defects anddue to load, medium caused new defects and harsh conditions make the fracturefailure accident increasing, so the pressure vessel security is also been concerned.Quickly and accurately find failure causes and failure rule is the effective way toreduce the accidents, at the same time, it has profound significance to prevent thepressure vessel accident effectively, improve equipment safe and reliable.The failure of pressure vessels including strength failure, according to thematerial mechanics knowledge, assume that pressure is no defects, according thematerial mechanics principle to evaluate the stress safety in pressure vessel, if thepressure vessel contain defects, we cannot evaluate the pressure vessel safety throughconventional approach, but using the fracture mechanics to evaluate the pressurevessel safety is viable.This paper taking a pressure vessel as an example,using finite element softwareABAQUS to build the three dimension finite element model of pressure vessel,through the analysis of pressure vessel macroscopic mechanical response to evaluatethe stress safety, using submodel technology simulate and compute more precisestress for pressure vessel hole area; for the defects pressure vessel, this paper basedon linear elastic fracture mechanics knowledge, building the plate model containdefects, according to materials fracture toughness and crack stress intensity factorvalue calculated the crack critical size, for inspection pressure vessel crack instabilityextension under service condition provides the evidence, through the finite elementsoftware ABAQUS simulate and calculate the stress intensity factor of semi-ellipticalsurface crack front, and show the accuracy and reliability of ABAQUS in calculationof stress intensity factor at the crack front. It also provides a method for calculationstress intensity factor on irregular crack front of complicated geometry.