The introduction of a Rule Engine in ORBIT+ Pipeline has opened a wide range of possible functions augmenting the totality of the system, ranging from portfolio assessments and initial prioritizations to direct assessment functions for both piggable and unpiggable pipelines.
The information available to pipeline engineers may vary from old and outdated data held on drawings, documents and excel sheets to fully quality assured and updated information for the pipeline systems. Companies are often faced with the problem on where to focus and where to spend the effort. The more pipelines they operate the more challenging these aspects are.
Introducing a rule based screener which relates to applicable threat conditions and defined consequence profiles may quickly isolate those pipelines potentially causing the largest risks and which subsequently shall be prioritised for more detailed studies to assess the real risk conditions. For unpiggable pipelines where the corrosion conditions may basically be unknown direct assessment methods applying the rule engine is instrumental to define the most probable locations along the pipeline where corrosion may occur. The rule based screener can correlate a wide range of pipeline data such as elevations, pressure, temperatures, soil conditions and earlier inspections readings. The rules may also be associated with high consequence area profiles and population density profiles, thereby deriving a measure of the current risk exposure. Screening results in a tabular form may be used to define locations along a pipeline as hotspots subject to separate risk assessments and potential mitigation actions like more detailed condition assessment as well as digging and repairing.
It is also an aspect of introducing a rule based screener in combination with view and review functions of inspection data, e.g. freespan, and upheaval buckling, that the inspection records are measured towards applicable design limits. Locations along the pipeline exceeding design limits are quickly picked out and thus subject to separate studies using more advanced analysis tools.
Applying quite simple engineering judgment rules on vas amounts of data proves to be of significant value, in particular to swiftly isolate areas along the pipeline which shall be subject to further investigations. Further work includes to combine engineering judgement rules with “Cost of Risk” rules, thereby assisting management in making the right priorities.
The rule engine in Orbit+ Pipeline enables definition of company specific rules ensuring that the often company restricted screening rules are not available to the public.
Authors: Anders Hvidsten and Jørgen Piene
Date: 2010-05-05