Consider all threats
The first step in managing pipeline integrity is identifying threats to a pipeline system. Regulations such as CSA Z662 or API 1160 require operators to consider all potential threats to their pipelines in their risk and integrity assessments.
These threats include:
- External and internal metal loss corrosion
- Excavation equipment impact
- Seam and girth weld cracks
- Stress corrosion cracking (SCC)
- Plain dents and dent gouges
- Incorrect operation and equipment failures
- Ground movement and other geotechnical hazards
- Dragged objects and vessel grounding (offshore pipelines only)
- Seismic hazards
- Collateral damage
Simplified and Advanced Models
PIRAMID addresses this need by providing a quantitative probability of failure model for each of the threats listed above that operators must consider. Within PIRAMID, there are two types of models used to estimate the probability of failure by small leak, large leak and rupture for each failure cause:
- Simplified models use only basic line attributes and operating conditions in combination with built‐in historical failure information, statistical correlations and simplified algorithms to assess the probability of failure.
- Advanced models can be used when more detailed data is available to calculate the failure probability using structural reliability models that define the load capacity of the pipe by accounting for the real world variability of the pipe properties, operating conditions and imposed loads.
Simplified and Advanced models can be combined in each analysis depending on what data is available for each threat. This allows analyses to be completed with the data that is currently available, but allows new data, such as inline inspection results, to be incorporated as it becomes available.