CPA Pipeline Operations & Integrity 2 — Questions and Answers
Question 1: What technology do 'smart pigs' (inline inspection tools) use to detect metal loss and corrosion in steel pipelines?
- Ground-penetrating radar
- Magnetic flux leakage (MFL) or ultrasonic testing (UT) (Correct answer)
- Infrared thermography
- Acoustic emission monitoring
Correct answer: Magnetic flux leakage (MFL) or ultrasonic testing (UT)
Smart pigs use magnetic flux leakage or ultrasonic sensors to detect wall thickness variations, corrosion, dents, and cracks from inside the flowing pipeline.
Question 2: Which type of valve is designed to automatically shut off flow when a pipeline experiences a sudden pressure drop indicating a rupture?
- Gate valve
- Check valve
- Automatic shutoff valve (ASV) / Emergency Flow Restrictor (Correct answer)
- Ball valve
Correct answer: Automatic shutoff valve (ASV) / Emergency Flow Restrictor
Automatic shutoff valves detect abnormal pressure conditions consistent with a rupture and close automatically to stop flow and limit product release.
Question 3: What is the primary cause of pipeline failures in the United States according to PHMSA incident data?
- Natural forces such as earthquakes and floods
- Corrosion (internal and external)
- Third-party excavation damage (Correct answer)
- Material defects from manufacturing
Correct answer: Third-party excavation damage
Third-party excavation damage — from digging, boring, or construction near pipelines — is consistently the leading cause of pipeline incidents in PHMSA data.
Question 4: The '811 Call Before You Dig' program in the United States is designed to prevent what type of pipeline hazard?
- Internal corrosion from product contamination
- Third-party excavation damage to buried utilities (Correct answer)
- Overpressure incidents at compressor stations
- Lightning-induced ignition of above-ground facilities
Correct answer: Third-party excavation damage to buried utilities
Calling 811 notifies pipeline and utility operators to mark underground lines before excavation, preventing accidental strikes that are the leading cause of pipeline incidents.
Question 5: What does a pipeline's 'integrity management program' (IMP) require operators to do on a scheduled basis?
- Replace all pipeline segments older than 25 years
- Assess, evaluate, and mitigate risks in high consequence areas (Correct answer)
- Install double-walled pipe in all populated areas
- Conduct daily aerial patrols of the entire pipeline route
Correct answer: Assess, evaluate, and mitigate risks in high consequence areas
IMPs require periodic risk assessments, inline inspections or pressure tests, and remediation of identified anomalies in high consequence areas per PHMSA regulations.
Question 6: Which condition in a natural gas pipeline can form solid ice-like plugs that block flow, particularly in cold or high-pressure environments?
- Wax deposition
- Hydrate formation (Correct answer)
- Scale buildup
- Asphaltene precipitation
Correct answer: Hydrate formation
Gas hydrates form when water molecules in natural gas crystallize around hydrocarbon molecules under high pressure and low temperature, creating solid plugs that block pipelines.
CPA Pipeline Operations & Integrity 2
What technology do 'smart pigs' (inline inspection tools) use to detect metal loss and corrosion in steel pipelines?