determination of damages mechanism and probability of failure, inspection plan part of piping system in a hydro processing unit by rbi method

In this article based on the accumulated practical experience in risk-based inspection(rbi) and also the api 580 ,581 , 570 standards, the limitations without consideration of original defects and taking design life as, the reference to calculating failure probability and writing an inspection plan in standard api 580 and 581 are analyzed with respect to the characteristics of severe defects and long-term service of part of pressure-bearing equipment's in our country, the concept and method that take residual life as the reference for calculation and assessment of failure probability are proposed in combination with the service conditions of pressure-bearing equipment's in our country, thus making rbi method more reasonable and improving the safety of rbi analytic results especially when the damage degradation mechanism of the equipment is time-dependent and coexists with oversized defects.