ILI vs DA—The Risk View

A rather common issue these days is decision making involving comparisons between In Line Inspection (ILI) vs Direct Assessment (DA, and, in particular, External Corrosion DA or ECDA).  You may need to research these techniques, if not already familiar to you, since we will assume the reader is fairly familiar with both. Both are acceptable […]

Damage vs failure: a risk assessment needs to know the difference

To measure resistance in a way most useful to a risk assessment, we must estimate the possible presence of weaknesses, the rate of emergence of future weaknesses, and the role of each weakness in strength reduction. By W. Kent Muhlbauer, WKM Consulting, Austin, TX, USA Since several of our recent columns have dealt with management-of-risk […]

Is this the same as SRA, LSD?

This recommended pipeline risk assessment methodology is similar to SRA (Structural Reliability Analyses) and LSD (Limit State Design) or LRFD (Load and Resistance Factor Design).  This is coincidental, since the methodology was developed independently from these techniques.  However, despite the similarities, there are key differences. Similarities include: Focus on engineering principles rather than incident history Accommodates […]

Pipeline Reliability–Service Interruption As ‘Failure’

Generally, a pipeline’s reliability includes consideration of all leak/rupture scenarios PLUS all other scenarios that could prevent the system from performing its intended function.  With the normal ‘intended function’ being something like:  deliver product to point B from point A at specified flow rates, pressures, temperatures, and product quality, a reliability failure occurs when any […]

Certifications: The Leaning Tree Incident

An operator recently experienced damage to their pipeline when a metal pipeline marker post was driven into the ground by a falling tree – the ‘leaning tree incident’. This is certainly not a common pipeline failure scenario. How much criticism against a risk assessment is warranted if this obscure event is missed? CERTIFICATION With growth in both the number of […]

Test Case Information

Complete package [sdm-download id=”375″ fancy=”0″ button_text=”Download”] (zip file) [sdm-download-counter id=”375″] Sketch View [sdm-download id=”377″ fancy=”0″ button_text=”Download”] (pdf file) [sdm-download-counter id=”377″] Dataset View [sdm-download id=”311″ fancy=”0″ button_text=”Download”] (xlsx file) [sdm-download-counter id=”311″] Instructions View [sdm-download id=”376″ fancy=”0″ button_text=”Download”] (pdf file) [sdm-download-counter id=”376″] Solutions view download registration required Upload:  Please make sure that you have included all of […]

Certification of Pipeline Risk Estimation Methodologies

How It Works This certification process tests a risk assessment methodology by having it produce risk estimates for three parallel pipelines for which risk-pertinent data is available.  A sketch and dataset details some relevant facts for each pipeline.  Many, but not all, common pipeline risk issues are illustrated or implied by the data provided. Someone […]