几种含体积型腐蚀缺陷管道剩余强度评价方法的特点及适用性

CHARACTERISTIC AND APPLICABILITY OF REMAINING STRENGTH EVALUATION METHODS FOR PIPELINES WITH VOLUMETRIC TYPE CORROSION-FLAWS

介绍了四种体积型腐蚀缺陷的评价方法,对比分析了其特点及适用性.结论为:ANSI/ASME-B31G适用于管材等级较低、管道服役年限长的老管道的评估,半经验、偏保守;DNV法可进行单个缺陷、相互作用的缺陷和复杂形状缺陷的评估;SY/T6151-1995法评价过程较复杂,但评价结果较准确;API RP 579-2000是目前较先进、较精确的分级评估方法,我国的SY/T6477-2000等效于它.

Corrosion is unavoidable in pipeline running. The volumetric type flaws, such as general corrosion and local corrosion are the chief factors that affect the pipeline safety. On the basis of investigations on domestic and abroad studies, we compared the characters and applicability of four popular methods for evaluation of the remaining strength of pipes for pipelines in serveice as well as those serviced for long time period. ANSI/ASME - B31G is suitable for the evaluation of the low grade pipes, however it is half experiential and conservative ; DNV can be used for the evaluation of effect of a single flaw, or inter-affected or complex flaws; SY/T6151 -1999 is complex, but the result is reliable. API RP 579 -2000 is the advanced and accurate one,it can even be used as grading method for pipes. SY/T6477 -2000 is similar to API RP 579 -2000.