Chloride Stress Corrosion Cracking

Question 1

1. Chloride Stress Corrosion Cracking (Chloride SCC) can cause cracks that normally initiate:

A. On the surface of any material
B. At the mid-wall of any material
C. On the surface of 300 Series SS
D. At the mid-wall of 300 Series SS

Answer 1

C. On the surface of 300 Series SS

Question 2

2. Which of the following is NOT a factor in the Chloride SCC?

A. Chloride strength
B. Material
C. Stress
D. Pressure
E. Temperature

Answer 2

D. Pressure

Question 3

3. Which of the following can contribute to Chloride SCC? (Open book)

A. Dissolved hydrogen
B. Dissolved oxygen
C. Dissolved nitrogen
D. Dissolved sulfide

Answer 3

B. Dissolved oxygen

Question 4

4. Heat transfer equipment can provide a way for Chlorides to:

A. breakdown
B. concentrate
C. React with sulfides
D. Vaporized.

Answer 4

B. concentrate

Question 5

5. Chloride SCC usually occurs at temperatures above:

A. 10°F
B. 140°F
C. 180°F
D. 225°F

Answer 5

B. 140°F

Question 6

6. Chloride SCC usually occurs at a pH: (open book)

A. Above 2 pH
B. Below 2 pH
C. Above 7 pH
D. Below 7 pH

Answer 6

A. Above 2 pH

Question 7

7. Which of the following components is most likely to crack from chloride SCC in a chloride environment?

A. Expansion bellows
B. Gate valve
C. Orifice plate
D. Seamless head

Answer 7

A. Expansion bellows

Question 8

8. Nickel alloys have the greatest susceptibility to Chloride Stress Corrosion Cracking when the nickel content is: (open book)

A. Less than 5%
B. Between 2.25% to 12%
C. Between 8% to 12%
D. Above 35%.

Answer 8

C. Between 8% to 12%

Question 9

9. Nickel is highly resistant to Chloride SCC when the nickel content in the alloy is above:

A. 8%
B. 12%.
C. 18%.
D. 25%
E. 35%

Answer 9

E. 35%

Question 10

10. Which of the following are common places were chloride SCC has been known to occur? *This may have more than one correct answer, please select all answers that apply. (Open book)

A. Crude tower overhead condenser.
B. Fluidized cat cracker regenerator
C. Boiler drain lines.
D. Vacuum flasher column.

Answer 10

A. Crude tower overhead condenser.

C. Boiler drain lines.

Question 11

11. External chloride SCC has been caused by chlorides in:

A. Wet insulation.
B. paint.
C. Steam vapor
D. UT couplant

Answer 11

A. Wet insulation.

Question 12

12. The fracture surfaces from Chloride SCC have a(n): (open book)

A. Autogenous appearance.
B. Brittle appearance.
C. Ductile appearance.
D. Oxidized appearance.

Answer 12

B. Brittle appearance.

Question 13

13. When insulating 300 SS equipment which of the following steps are important?

A. Do not insulate if the metal temperature is less than 225°F.
B. Do not use fiberglass insulation.
C. Add a coating to the equipment prior to insulating
D. Use SS insulation sheathing to prevent galvanic corrosion.

Answer 13

C. Add a coating to the equipment prior to insulating