腐蚀管道剩余强度评价方法的对比研

综述了ASME B31G-1984、ASME B31G-1991、DNV RP-F101以及PCORRC等4种腐蚀管道剩余强度的评价方法，从安全准则、适用缺陷类型、适用管材强度等级等几个方面进行了分析、比较。基于全尺寸爆破试验结果验证，指出修改后的ASME B31G的保守性有所降低，但仍然存在较大的安全裕量。PCORRC和DNV采用了基于爆破强度的安全准则，因此更适应中、高强度等级管道的缺陷评定。计算并分析了流变应力的选取、腐蚀面积的简化计算、Folias鼓胀因子等因素对腐蚀管道剩余强度评价结果的影响程度。旨在便于评定人员选取合适的评价方法，进而提升管道安全运营管理水平。

COMPARISON STUDY ON ASSESSMENT METHODS FOR REMAINING STRENGTH OF CORRODED PIPELINE

This paper presented a review on ASME B31G-1984, ASME B31G-1991, DNV RP-F101 and PCORRC methods in evaluating the remaining strength of corroded pipeline. These four methods were generalized and compared in safety criterion and fitness for defect type and strength grade of pipeline steel. Based on the validation with full scale burst test data, it is pointed out that B31G modified in 1991 has less conservation than the initial B31G method presented in 1984, but it should be still improved because it has much safety marginal. DNV RP-F101 and PCORRC method applied the limit tensile strength of pipeline steel in the formula about the burst failure pressure of pipeline, thus they are suitable for pipelines with moderate to high strength grade. The paper further computed and analyzed the effect of the access of flow stress, simplified calculation of corrosion area and the Folias factor on the assessment result about the remaining strength of corroded pipelines. It aimed to make it easy to select appropriate assessment method for assessment personnel and thus to advance pipeline safety control level.