Stress Analysis And Failure Risk Study Of Industrial Water Tube Boiler Drum

This paper takes the actual production of Kunming Boiler Co.,Ltd.as the background,and takes the SZL4-1.25-AII type water tube boiler as the research object.Based on the theory of drum stress analysis and failure risk research,the following contents are studied: 1)The specific analysis of human factors,equipment factors,environmental factors and management factors during the operation of the drum is carried out.The Bow-tie model technique is used to analyze the risk of drum failure in a forward and reverse direction to identify various sources of danger during the operation of the drum and to identify threats and possible consequences.Barriers and upgrade safety factor measures are set to ensure the normal operation of the drum,and to propose measures to prevent the failure of the drum and suggestions for use.2)Set theory are used to carry out safety assessment on human factors,equipment factors,environmental factors and management factors during the operation of the drum to determine the safety level of the drum operation and to propose countermeasures.3)In this paper,the SZL4-1.25-AII water tube boiler actually produced by Kunming Boiler Co.,Ltd.is used as the simulation research object,and the finite element analysis model is established.The cold state of the boiler drum is quickly started and heated by ANSYS finite element software.Three representative working conditions,such as start-up and emergency shutdown,were studied.The equivalent stress and equivalent strain state of the drum wall under the three working conditions are simulated.At the same time,the thermal stress,mechanical stress,and the transient change trend of the coupled stress are analyzed,and the analysis cloud map is generated and the corresponding data curve is generated,which can clearly see the heat distribution and stress concentration tendency of the drum.4)According to the simulation results,the maximum temperature of the drum wall and the stress concentration trend at the opening of the lower surface of the drum can be seen in the three conditions of cold start,hot start and emergency stop.At the same time,the relationship between thermal stress,mechanical stress and thermal and mechanical stress coupling under these three working conditions is also analyzed,and the safety degree(equivalent stress and equivalent strain)of the drum structure is analyzed.Finally,the results of three working conditions analysis are combined,and the S-N curve is used to analyze the life-fatigue damage area of the drum.