The Research On Quantitative Risk Evaluation Of RBI Methodology In Gas Pipeline Systems

Long-distance gas pipeline is the safest and most economical mode of transportation.However,because of flammable and explosive characteristics of the nature gas,once an accident happens,which will lead to vicious consequences such as fires and explosions and adverse social impact.Therefore,the risk management of the gas pipeline system attracts the attention of various aspects,the development and perfection of these technologies admits of no delay.Risk-based Inspection(RBI)that has been arisen and developed in western countries,in the past 30 years is a concept and method of system management which combines security and economic.Risk-based Inspection is one of the key technologies of risk management of pipelines.It is on the basis of risk assessment,through the implementation of a risk-based pipeline inspection and evaluation to get the status of pipeline,which can be raised the most appropriate maintenance programs and prevent the emergence of high maintenance costs and pipeline accidents.It is an important mean that ensure the operation of the pipeline in-service safety and economic. Application of RBI is in a wide range,but in the view of the current circumstances,it is an attempt that RBI is applied to the risk assessment of the gas pipeline systems.In this paper,firstly,the basic tenet of RBI technology was introduced and the risk analysis methodology and the implementation process of RBI were explained.In view of the gas pipeline system,the quantitative risk evaluation model of RBI was in-depth analyzed and researched,and then the Equipment Modification Factor(F_E) was modified that ascertained the three failure models,thinning,stress corrosion cracking,external corrosion,which associated with damage mechanism in gas pipelines,furthermore the factor of third-party damage of gas pipelines was taken into account,finally the RBI quantitative risk assessment model of gas pipeline system was established.On the basis of the RBI quantitative risk assessment model of the gas pipeline system,the risk assessment software for gas pipeline system was developed with the object-oriented method.The software system has friendly and wieldy interface that is easy to use.The software system is maintained and expanded easily.By surveying She-Ning-Lan gas pipeline,the data were collected,then the RBI quantitative risk assessment of the gas pipeline system was done by using the software,the result of the risk ranking was carried out,which provided scientific basis for the operation and management of the pipelines.