Study Of Pressure Vessel's Openings And Reinforcements Based On Reliability Theory

After the pressure vessel's opening, the continuity of the structure is destroyed and it became the destruction of a container source. So it needs for reinforcement design. The conventional design method is generally more conservative and easily leads to waste of materials. Because of not considering the errors caused by the uncertainty of the strength of pressure vessels, stress and the geometric parameters, it is not discrepanciing with the actual. So it can not guarantee the absolute safety. The reliability design method not only saves materials, but also pre-estimates the reliability of design objects. Therefore, that the reliability design method is introduced to the design of pressure vessels has become a trendThis paper elaborates that reliability design is a new design method which is used in the design of pressure vessel's openings and reinforcements, and investigates the interference theory of stress-strength model used in the design of pressure vessel's openings and reinforcements. The author combines with reliability design and openings and reinforcements by using national standard, traditional method and reliability design, at the same time obtains reliability advancedly. Supposing that all the random variables are submitted normal distribution, we can get a safety factor according to the reliable tolerance. This paper designs the thickness of pressure vessel's openings and reinforcements by combining tapping calculating formulas with reliability formulas, and find out the thickness of pressure vessel's openings and reinforcements in traditional method. Then contrasting the results which come from different methods, the author concludes that reliability design not only saves stuff, but also reflects the reliable degree. At last this paper does finite element analysis in the results of the engineering instance using the thickness,pressure load and elastic modelling quantity as the random input, which demonstrates that reliability design can meet the respective needs both in economy and facility.