At the 2016 International Pipeline Conference (IPC), C-FER employees are involved in presenting seven papers across a wide range of pipeline topics. A summary of each paper is given below:
THE BENEFITS OF ACCURATE ILI PERFORMANCE ON PIPELINE INTEGRITY PROGRAMS FOR AXIAL CRACK AND METAL LOSS CORROSION THREATS (IPC2016-64612)
C-FER employees: Riski Adianto and Jason Skow
An analysis describing the benefits of an accurate in-line inspection (ILI) system performance is presented in this paper. A good ILI performance is characterized as an accurate description of the condition of an inspected pipeline. Information from a better ILI performance, as compared to a poorer one, can be used to reduce the number of required digs and/or extend the re-inspection interval without compromising the pipeline’s integrity. As a result, these parameters can be used to assess the benefits of the improved inspection performance.
C-FER employees: Smitha Koduru and Dongliang Lu
Bayesian networks offer an intuitive method of modelling causal relationships between the triggering events that lead to equipment impact on a pipeline. This method offers an advantage over the more well-known fault-tree methods due to its ability to use Bayesian inference for updating the prior probabilities of triggering events that lead to equipment impact such as, failure of permanent markers, use of one-call system, failure of right-of-way patrol. In this paper, a modelling approach for a Bayesian network for equipment impact assessment, based on the available fault-tree method, is demonstrated.
Assessment of Corrosion Anomalies Under Large Longitudinal Strains (IPC2016-64628)
C-FER employees: Brent Ayton and Jason Bergman
The analysis and experimental results shown in this paper formed the bases for developing the assessment procedures and guidelines for the corrosion anomalies in pipelines subjected to large longitudinal strains.
Analyzing the Effectiveness of Prevention Measures for Third-Party Damage to Underground Pipelines Using a Hierarchical Fault Tree Model (IPC2016-64611)
C-FER employees: Dongliang Lu and Mark Stephens
This paper presents a hierarchical fault tree model for analyzing the effectiveness of measures for the prevention of third‑party mechanical damage to underground pipelines. The model consists of a high level failure model that provides an overall indication of the effectiveness of a damage prevention program; and lower level fault tree models that detail the effectiveness of individual damage prevention measures.
Effect of soil variability on strain demand associated with moving slopes (IPC2016-64432)
C-FER employees: Alex Fraser and Smitha Koduru
In this paper, a finite element analysis of pipe-soil interaction is employed to assess the influence of soil variability on strain demand. Strain demand is shown to be highly influenced by variability in slope movement parameters and soil properties. Strategies to reduce the variability in the strain demand either through increased data collection or through pipeline design are discussed.
INFLUENCE OF MATERIAL ANISOTROPY ON THE COMPRESSIVE STRAIN CAPACITY (IPC2016-64293)
C-FER employees: Smitha Koduru, Alex Fraser and Qishi Chen
This study presents a new approach for the representation of material anisotropy in FE models and demonstrates the influence of material anisotropy on the compressive strain capacity with the aid of two case studies using pipeline materials for X60 and X80 grade steel. Results indicate that material anisotropy reduces the compressive strain capacity by up to 30% compared to the capacity prediction using axial tension material properties. If material anisotropy is to be ignored, in order to assess the lowest value of compressive strain capacity it is recommended that the material representation with highest yield strength and yield to tensile strength ratio be selected among the hoop tension, axial tension, and axial compression coupon test results.
EFFECT OF BLOCK VALVE AND CRACK ARRESTOR SPACING ON THERMAL RADIATION HAZARDS ASSOCIATED WITH IGNITED RUPTURE INCIDENTS FOR NATURAL GAS PIPELINES (IPC2016-64604)
C-FER employee: Thomas Dessein
A study was undertaken to evaluate crack arrestor and mainline block valve (MLBV) spacing distances beyond the limits defined in the 49 CFR Part 192 for Class 1 locations for the design of a 42‑inch (1,067‑mm) OD arctic pipeline. The study assessed whether an MLBV spacing longer than that required by 49 CFR Part 192 for Class 1 locations can provide a level of safety equivalent to that afforded by the spacing recommended in the code. This was accomplished by comparing the hazards in terms of the volume of natural gas released over time, the potential for damage to surrounding structures, and the life safety risk to personnel and the public.