Comparison of Methods for Calculating the Inspection Interval in the Implementation of a Risk-based Approach to the Inspection of the Process Equipment


The article deals with the problems of conducting periodic inspections of equipment. This is due to the high frequency of equipment shutdown for its technical diagnostics and examination in accordance with the requirements of regulatory and technical documentation, in particular the Federal norms and rules «Rules for the safe operation of process pipelines». 

It is noted that the inspection is an important tool for ensuring the integrity of the equipment and, as a result, the industrial safety of the facility. At the same time, it is indicated that the inspection can be implemented on the basis of one of two approaches: regulated and risk-oriented.

A general description of the inspection methodology, taking into account risk factors, is presented. It is pointed out that a risk-based approach to inspections is widespread in a number of countries. Various methods of implementing this approach are given, taking into account a large number of standards. The basics of API 581 3rd Edition and S-RBI techniques used for inspections are described.

The technological process of the gas condensate stabilization system of a plant for the production of liquefied natural gas is described. A process pipeline is considered as an object of the study, for which an inspection interval is determined using the API 581 3rd Edition methodology.

At the first stage of determining the inspection interval according to the S-RBI methodology, the process of assessing the criticality of the failure is described. The second step describes the process of determining the confidence factor, where the focus is on the estimation of the uncertainty in predicting the corrosion rate. At the third stage, the coefficient of the inspection interval is determined based on the data on the criticality of the failure and the reliability factor. Then an example of calculating the inspection interval for the object under study is given.

Based on the results obtained, a conclusion was made about the comparability of API 581 3rd Edition and S-RBI methods. Both methods have their advantages and disadvantages, but at the same time they provide optimization of the scope of inspection work while maintaining a high level of industrial safety of the facility. In order to improve production efficiency, reliability and safety of pressure equipment, and optimize inspection intervals (which will allow to reduce the financial costs of enterprises), it is advisable to apply the above practices in the Russian Federation, providing the required legal and regulatory framework.

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DOI: 10.24000/0409-2961-2023-7-21-27
Year: 2023
Issue num: July
Keywords : industrial safety risk-oriented approach calculation algorithm production efficiency inter-inspection interval S-RBI methodology equipment integrity regulatory framework inspection