Research On The Establishment Of RBI Technology Model For Power Plant Boiler

With the rapid development of electric power industry,the thermal power enterprise expands unceasingly the installed capacity and the turbine.As one of the important equipments in the power plant boiler system,the safe and stable operation of power plant boiler plays a vital role.Because of its high technological parameters and medium temperature,it will lead to serious consequences for the equipment and circumjacent environment when an accident happen.Therefore, power plant boiler risk management has attracted more and more social attention of various aspect.Risk-based Inspection which is one of the key technologies of risk management based on the risk assessment,has been considered by the western developed countries as a new type of system management principles and methods in the pursuit of the unity between safety and economy in recent three decades.It can refrain from the emergence of high maintenance costs and effectively prevent the incidence of equipment accidents through the implementation of a risk-based equipment inspection and evaluation to get the status of the equipment and then put forward a feasible program of risk control.It is an important means that ensure the safe and economic operation of the current equipment.The RBI is in a wide range of application,however,there is no RBI software can be completely used for boiler system at the moment at our country.This paper firstly presents elementary principles of RBI and its historical development in the world.In addition,the risk analysis methodology and implementation scheme for RBI is introduced as well.Seven failure modes relative to the failure mechanisms in the power station boiler system were identified and the RBI risk assessment model of the power station boiler has been established via an in-depth and systematic analysis and study.Since the failure probability of the similar equipments in API 581 does not apply to the power station boiler in our country,this thesis proposed statistical methods for the failure probability of the power station boiler according to the pressure vessel and the failure probability obey the normal distribution.Given that long term service and unreasonable defect occur frequently in the power station boiler in our country,the paper adopted residual life correction factor (FL)to modify the likelihood of failure(LOF).And since the influence of vapour explosions on the equipments and staff is not taken into account,we identified the casualty radius and property damage radius by using over pressure impulse standards as vapour explosion casualty standards.In this paper,the RBI risk assessment model was employed to carry out the risk assessment of the steam drum of the power station boiler. The level of risk was confirmed through the analysis and calculation of the likelihood of failure and consequence of failure. The RBI inspection planings and recommendations of the the steam drum was fixed on in the light of the analysis resuls,too.