Study On Intelligent Decision-making Of Inspection And Maintenance Based On Risk And Condition For Petrochemical Equipment

In this paper, intelligent decision-making method for inspection and maintenance based on risk and condition is studied to accomplish quantitative risk management of equipment including pressure vessel and pipe in petrochemical plants etc. According to lots of cases and data from petrochemical plants, the theory of terotechnology and the quantitative method of risk engineering are used to extend the risk management to more wide fields such as design, manufacturing, installation, running, inspection and maintenance.On the aspect of system frame, the damage status is introduced into the risk-based decision-making to establish a risk and-condition-based decision-making frame. Besides, through discussing the theoretic model of risk-based decision-making, the view is pointed that the two of the important factors to determine the control of risk are the damage value and damage status and the risk is taken as the simplex aiming of controlling risk to result the exorbitant costs of plants, so that it is rational that the damage status is introduced into the simplex risk-based decision-making as a factors of decision-making.On damage status monitoring of equipment, the damage status is defined including the damage mechanism, severe damage location, damage type, damage severity and damage rate and a series of qualitative and quantitative algorithms are proposed to determine the damage status. On the risk assessment, for resolving the problems, quantitative risk assessment of inner leakage and impact of maintenance in running, the quantitative algorithms is modeled for assess the two problems.On the damage status monitoring, a multi-parameter in-service inspecting method, which combined the damage monitoring and damage diagnose, is established to change the passive inspection to the positive damage monitoring and damage causes diagnose for affording the effective data for the following inspection and maintenance decision-making.On the inspection decision-making, the recommended inspection date (or inspection frequency) are determined based on the damage and risk status assessed in the previous parts. On the maintenance decision-making, the repairing and re-design plans will be determined based on damage status, conclusion of damage diagnose and risk for accomplishing the multi-objective optimization on the safety and economy.