Session: 07-04-01 Integrity Threats

Paper Number: 133994

133994 - Hard Spot Management Framework for Gas Transmission Pipelines Using Risk-Based Approach 

Abstract: 

The presence of hard spots is a concern for gas transmission pipeline integrity management because these manufacturing defects can fail under normal operational stress in the presence of atomic hydrogen. Considering recent pipeline failures associated with hard spots, there is an opportunity for pipeline operators to establish a robust and efficient hard spot integrity management program. Currently many pipeline operators use industry susceptibility studies conducted in the early 2000s as a basis for their hard spot integrity management program. These studies identified that susceptibility to the hard spot threat is mostly associated with a specific pipeline steel plate manufacturer. However, these studies were limited by incomplete failure data, and lack of length-normalization, rendering them inadequate for comprehensive reliability and risk analysis. A systematic review of existing hard spot data and recent study performed by PRCI (project MAT-7-2) suggests susceptibility to hard spots across a broader range of manufacturers and operating conditions. First, this paper discusses operators’ experience with hard spot threat outlining learnings, findings, and challenges Then, this study explores the application of PRCI MAT-7-2 susceptibility criteria, integrating them into a risk-based methodology to guide informed decisions in the pre in-line inspection stage, with the goal of establishing future inspection plan. Next, the study extends to a post in-line inspection review of hard spots, using a risk-based approach to mitigate potentially injurious features. To accomplish this, the study explores a structural reliability approach using a hard spot failure pressure model applied in a Monte Carlo simulation. This helps to rigorously account for uncertainties and quantify the probability of failure, considering essential factors such as the type of hard spot, its dimensions and hardness, etc. A case study of hypothetical pipeline susceptible to hard spot is included to demonstrate the practical application of the proposed framework in effectively managing the threat in gas transmission pipelines.

Presenting Author: Oleg Shabarchin Enbridge GTM

Presenting Author Biography: Will be provided later

Authors:

Oleg Shabarchin Enbridge GTM
Austin Janousek Enbridge GTM
Brady Bolf Enbridge GTM
Sean Moran Williams
Kelly Thompson Williams
Owen Malinowski Structural Integrity Associates