NACE Corrosion Monitoring Techniques 2

Question 1

Electrochemical Noise (EN) monitoring detects corrosion by measuring:

Accepted Answer

Spontaneous fluctuations in potential and current that reveal corrosion mechanisms

Answer

Acoustic noise generated by vibrating corroding metal

Answer

Electrical interference caused by cathodic protection systems

Answer

Ultrasonic reflections from corrosion pits

Question 2

A Zero Resistance Ammeter (ZRA) is used in corrosion monitoring to measure:

Accepted Answer

Galvanic current flowing between two dissimilar metals coupled together

Answer

Corrosion potential against a reference electrode

Answer

Electrical resistance of a corroding pipeline segment

Answer

Soil resistivity around a buried structure

Question 3

The Field Signature Method (FSM) monitors corrosion by:

Accepted Answer

Mapping wall thickness changes using an array of pin electrodes that measure resistance patterns across a pipe section

Answer

Using electromagnetic fields to detect coating defects from the pipe exterior

Answer

Monitoring cathodic protection current distribution along the pipeline

Answer

Tracking inhibitor film coverage on pipe walls using fluorescent tracers

Question 4

What is the main advantage of online corrosion monitoring over offline inspection methods?

Accepted Answer

Online monitoring provides continuous data without removing equipment from service

Answer

Online monitoring is always less expensive to install and maintain

Answer

Online monitoring requires no calibration or maintenance

Answer

Online monitoring can identify specific corrosion product chemistry

Question 5

When calculating corrosion rate from a corrosion coupon, which piece of data is NOT required for the standard calculation?

Accepted Answer

Ambient temperature during the exposure period

Answer

Initial weight of the coupon before exposure

Answer

Final weight of the coupon after cleaning

Answer

Exposure time in the corrosive environment

Question 6

What is a key limitation of Linear Polarization Resistance (LPR) probes that restricts their application?

Accepted Answer

They require a conductive electrolyte and are unreliable in low-conductivity environments

Answer

They can only measure cathodic half-reactions

Answer

They cannot detect any form of localized corrosion

Answer

They must be physically removed from service for data download

Question 7

Sand/erosion monitoring probes are deployed in corrosion monitoring programs primarily to detect:

Accepted Answer

Mechanical metal loss caused by particle impingement distinct from electrochemical corrosion

Answer

Microbiological activity and SRB populations in pipelines

Answer

Scale and mineral deposit formation on pipeline walls

Answer

Hydrogen blistering damage from sour service conditions