管道内检测缺陷尺寸量化精度的可靠性评价方法

管道内检测缺陷尺寸量化精度的可靠性直接影响着管道完整性评价结果,进而影响管道维修计划的制定及再检测时间的确定。将SY/T 6825—2011《管道内检测系统的鉴定》与API Std 1163-2013《内检测系统的鉴定标准》进行对比,厘清了可靠性与置信度的定义及关系,对中国管道内检测缺陷尺寸量化指标的基本概念进行了修正。结合API Std 1163-2013相关规定,并基于AgrestiCoull方法,建立了管道内检测缺陷尺寸量化精度的可靠性指标计算方法,给出了判断内检测服务商提供的管道内检测缺陷尺寸量化精度指标的可接受准则,为管道运营企业选择和验证内检测缺陷尺寸量化精度指标提供了依据。(表4,参25)

Assessment method for the reliability of quantization precision of pipeline in-line inspection defect size

The results of pipeline integrity assessment are directly affected by the reliability of quantification precision of the in-line inspection defect size,and accordingly,the determination of maintenance plan and re-inspection time will be affected.By comparing In-line inspection systems qualification(SY/T 6825-2011)with In-line inspection systems qualification(API Std 1163-2013),the definition and relationship between reliability and confidence were clarified,and the basic concept of quantitative index of in-line inspection defect size in China was revised.With reference to the relevant provisions of API Std 1163-2013,the reliability index calculation method for quantization precision of in-line inspection defect size was established based on Agresti-Coull method,and the acceptance criterion for judging the quantization precision index of inline inspection defect size provided by the in-line inspection service providers was demonstrated,providing the basis for pipeline operators to select and verify the quantification precision index of in-line inspection defect size.