Module 4

Question 1

Sensitization:

Answer 1

At high temperature (700 – 1500°F) chrome carbides precipitate continuously along grain boundaries in metal microstructure. Deplete matrix of Cr

Question 2

In general, ________ grained microstructures tend to perform better than _________ grained.

Answer 2

Fine, Course

Question 3

Corrosion Fatigue - The first sign of damage in a cycling boiler will be where?

Answer 3

Cold side of waterwall tube at buckstay.

Question 4

If the desalter is malfunctioning, where will the majority of the corrosion show up?

Answer 4

Crude Unit

Question 5

What type of crude delivery system is most prone to extreme variations?

Answer 5

Truck

Question 6

Alloy 400 in atmospheric overhead system that has become embrittled is probably due to the presence off what?

Answer 6

mercury ( LME)

Question 7

Alloy 400 in atmospheric overhead system that has become embrittled is probably due to the presence off what?

Answer 7

mercury ( LME)

Question 8

Which of the following best describes the reason for utilizing corrosion inhibitors in Ethanol gasoline blends?

Answer 8

Mitigation for general corrosion.

Question 9

A material with _________ grained material will have better creep strength than a _______ grained material.

Answer 9

Coarse, Fine

Question 10

Low creep ductility is more likely in a _________ grained material than a _______ grained material.

Answer 10

Coarse, Fine

Question 11

Low creep ductility is more likely in a _________ grained material than a _______ grained material.

Answer 11

Coarse, Fine

Question 12

Which of the following poisons the formation of molecular hydrogen (H2)?

Answer 12

cyanide