抽样方案变化对聚能射孔器穿孔深度评价体系的影响

Influence of Sampling Plan Change on Perforation Depth Evaluation System of Shaped Charge Perforator

抽样方案的变化影响聚能射孔器穿孔深度检验的严格程度。在起草SY/T 6163—2018《油气井聚能射孔器通用技术条件及性能试验方法》时,检索到拟引用标准更新导致抽样方案中的样本量、接收常数发生了变化,为了保持抽样方案的连续性,沿用了GB/T 20489—2006旧标准中的抽样方案。以外径89 mm聚能射孔器为例,对比分析了不同时期评价标准中穿孔深度抽样方案及对应合格率,发现SY/T 6163—2018中给出的接收质量限(AQL)值有偏差且合格率偏高。建议使用新的穿孔深度抽样方案:检验水平为Ⅰ、接收质量限为2.5、样本量为18孔/m和接收常数(k)为1.429,更加科学地评价穿孔深度质量水平。

The change of sampling plan affects the strictness of perforation depth inspection of jet perforator.When drafting SY/T 6163-2018“General specifications and test methods of shaped charge perforating equipment for oil and gas well”,it was found that the renewal of the cited standard resulted in the change of sample size and receiving constant in the sampling plan.In order to maintain the continuity of the sampling plan,the sampling plan in the old standard GB/T 20489-2006 was used.Taking the shaped charge perforator with the outer diameter of 89 mm as an example,the sampling plans of perforation depth in different evaluation standards and the corresponding qualified rates are comparatively analyzed,and it is shown that the acceptance quality limit(AQL)value given in SY/T 6163-2018 has deviation and the qualified rate is high.It is suggested to use a new sampling plan for perforation depth:the inspection level is I,the acceptance quality limit(AQL)is 2.5,the sample size is 18 holes/m and the acceptance constant(k)is 1.429,which is helpful to evaluate the quality level of perforation depth more scientifically.