Numerical investigation on sealing performance of drainage pipeline inspection gauge crossing pipeline elbows

A pipeline inspection gauge (PIG) is routinely passed throughout the long-distance oil and gas pipelines by operators to clean pipeline. Sealing performance a significant evaluation index for PIG's safety operation. To comprehensively evaluate seal performance, nonlinear finite element models were developed, parametric analysis was conducted in this study. The accuracy of simulation model validated from numerical experimental results reported literature. show that comparing with pigging straight pipes, sealing rubber cups PIGs can be more easily detached pipe wall when passing through elbows, causing smaller areas. For typical elbow (with curvature radius equals six times diameter) widely used industry, minimum area cup only 8.07% during common operation conditions. ability obviously enhanced increasing small elbow. Elbow slightly affects cup's behavior over pipe's outer diameter. An increment interference increase contact between wall, blockage risk will reduced due good sufficient driving force. required 4% under most condition; is, thickness, fluid pressure difference, friction coefficient are 35 mm, 0.02 MPa, 0.3, respectively. proper decrease thickness reduce stiffness cups, indicating prone deformation. Thus, an differential PIG enhance separated wall. large risky safe region coefficient. In engineering practice, measures should taken Above all, obtained study provide reference structural design PIGs.