SPED Corrosion Prevention & Protection 2

Question 1

Which type of corrosion occurs when two dissimilar metals are in electrical contact in the presence of an electrolyte?

Accepted Answer

Galvanic corrosion

Answer

Galvanic corrosion occurs when dissimilar metals form an electrochemical cell in the presence of an electrolyte, causing the anodic metal to corrode preferentially.

Question 2

In cathodic protection, which component of the system is intentionally corroded to protect the structure?

Accepted Answer

Anode

Answer

In cathodic protection, the anode (sacrificial or impressed current) oxidizes and corrodes to supply protective current to the cathode (the structure being protected).

Question 3

What is the primary mechanism by which fusion-bonded epoxy (FBE) coating protects buried pipelines?

Accepted Answer

Acting as a physical barrier to moisture and oxygen

Answer

FBE coatings protect pipelines primarily by acting as a physical barrier that prevents moisture, oxygen, and electrolytes from reaching the pipe surface.

Question 4

Which parameter is used to verify adequate cathodic protection of a pipeline per NACE SP0169?

Accepted Answer

-0.850 V vs. CSE

Answer

NACE SP0169 specifies a minimum pipe-to-soil potential of -0.850 V (vs. copper-copper sulfate electrode) as the criterion for adequate cathodic protection.

Question 5

Stress corrosion cracking (SCC) in pipelines requires which three conditions to occur simultaneously?

Accepted Answer

Susceptible material, tensile stress, and corrosive environment

Answer

SCC requires the simultaneous presence of a susceptible material, sufficient tensile stress, and a specific corrosive environment — remove any one and SCC cannot initiate.

(SPED) Society of Piping Engineers and Designers Certification Practice Test

(SPED) Society of Piping Engineers and Designers Certification Practice Test

SPED Corrosion Prevention & Protection 2