Figures (6)  Tables (2)

    • Figure 1. 

      Pipeline corrosion sample.

    • Figure 2. 

      Cumulative probability distribution law of local maximum corrosion depth of the pipeline.

    • Figure 3. 

      Probability distribution curve of corrosion depth.

    • Figure 4. 

      Distribution of corrosion depth under different correlation coefficients.

    • Figure 5. 

      Trend diagram of system failure probability with correlation coefficient of pipeline corrosion defects.

    • Figure 6. 

      Trend diagram of system failure probability with pipeline corrosion defects.

    • ParameterAverage valueVariable coefficientUnitDistribution form
      Axial length of corrosion defect (L)3035%mmLogarithmic normal distribution
      Outer diameter (d)601%mmNormal distribution
      Maximum annual internal pressure (p)0.259−MpaDefinite value
      Thickness (t)41.5%mmNormal distribution
      Yield strength $ ({\mathit{\sigma }}_{\mathit{u}} $)2353%MpaNormal distribution
      Accuracy coefficient of model ($ {\mathit{x}}_{\mathit{m}} $)0.9710.5%−Normal distribution

      Table 1. 

      Pipeline parameters and probability distribution form.

    • Sample numberResidual pipe wall thickness (mm)Sample numberResidual pipe wall thickness (mm)
      13.1283.56
      23.4893.43
      33.67102.58
      43.60113.28
      53.46122.98
      63.74133.37
      73.68143.44

      Table 2. 

      Residual wall thickness of pipeline.