Study On Lifetime Prediction And Safety Monitoring Technology Of Bursting Disc

For the long-term use of bursting discs without overpressure blasting,whether they can continue to be used for a long time and whether they need to be replaced has become a difficult problem for enterprises and regulatory agencies.The essence of the replacement period of bursting discs is the service lifetime of bursting discs.At present,there is no quantitative prediction method for the service lifetime of bursting discs.In addition,although periodic replacement by lifetime prediction is a method to prevent the failure of bursting discs,if the online monitoring of bursting discs can be realized,the problem of failure prevention of bursting discs can be solved eventually.However,no relevant studies have been conducted for this aspect.In view of this,this paper selects the bursting disc as its research object,carries out a systematic study on the prediction of its lifetime,and explores the feasibility of applying optical fiber and acoustic emission sensing technology to the safety and health monitoring of bursting discs.The main contents and conclusions are as follows:（1）The room temperature lifetime test platform of conventional domed bursting disc was set up to compare the lifetime changes of 316L and Inconel600 conventional domed bursting discs with the best pre-arch forming pressure.316L and Inconel600 conventional domed bursting discs have the same lifetime rule at room temperature,which is shown in the result.The static endurance lifetime t（min）of bursting disc under constant load and the fatigue lifetime N（Times）under fatigue reciprocating load decrease with the increase of operation ratio W.The static endurance lifetime and fatigue lifetime prediction formula of 316L and Inconel600 conventional domed bursting discs are obtained by fitting.The prediction formula of endurance lifetime:t=8.0087W^-70.92The prediction formula of fatigue lifetime:N=201.547W^-11.02（2）The high temperature lifetime test platform of conventional domed bursting disc was set up to compare the lifetime changes of 316L and Inconel600 conventional domed bursting discs with the best pre-arch forming pressure at the temperature of 150℃.The lifetime of conventional domed bursting disc increases at the temperature of 150℃compared with that at room temperature,and decreases with the increase of operating ratio W,which is shown in the result.The static endurance lifetime prediction formula of 316L and Inconel600 conventional domed bursting discs at the temperature of 150℃is obtained by fitting.The prediction formula of endurance lifetime of 316L:t=3.567W^-81.566The prediction formula of endurance lifetime of Inconel600:t=0.332W^-106.383（3）The experimental platform of high temperature and lifetime of ultra-high pressure bursting discs was set up,and the static endurance lifetime of bursting discs with the best pre-arch forming pressure under different operation ratios was studied.The results show that the low pressure bursting disc and the ultra-high pressure bursting disc have the same lifetime characteristics.The lifetime rule of ultra-high pressure bursting disc can be inferred by studying the lifetime of low pressure bursting disc.The research results have a certain practical significance for the formulation of the lifetime prediction formula of ultra-high pressure bursting discs.（4）Considering the difference between the service lifetime of the bursting disc under the experimental conditions and that in the practical engineering application,it is necessary to define the safety factor to modify the formulas of the static endurance lifetime and fatigue lifetime of the conventional domed bursting disc.The safety factors of the two are 15 and 20respectively.Finally,the lifetime prediction formula of bursting discs suitable for practical engineering application is obtained.（5）The feasibility of optical fiber and acoustic emission sensing technology to safety monitoring of bursting discs is explored,and the experimental platform for safety monitoring of conventional domed bursting disc and reverse domed bursting disc were set up.The results show that the optical fiber and acoustic emission sensing technology can be used to monitor the safety of conventional domed bursting disc.There are two kinds of early warning methods for fiber optic monitoring,which can take the sudden jump of fiber Bragg grating center wavelength signal or the disappearance of fiber Bragg grating center wavelength signal as the corresponding early warning signal;There are three kinds of early warning methods for acoustic emission monitoring,which can take the large number of acoustic emission signals and sudden jump phenomenon,the amplitude of acoustic signal exceeding 70 d B or the acoustic emission b value tends to be stable as early warning signal.But for the reverse domed bursting disc,the safety monitoring can not be carried out by these two monitoring methods.