- CUI is caused by:
A. water trapped under insulation
B. water trapped under insulation or fireproofing
C. trapped water reaching the water’s boiling at the metal surface
D. water reacting with insulation to form a strong corrosive acid
B. water trapped under insulation or fireproofing
- Concerning CUI which of the following are true?
A. Corrosion pattern is usually uniform corrosion
B. Corrosion rate increases as temp increases up to where water rapidly vaporizes
C. The location of corrosion is always very predictable
D. Corrosion does not occur above 212F (water’s boiling point)
B. Corrosion rate increases as temp increases up to where water rapidly vaporizes
- CUI is a possibility on insulated Carbon Steel equipment that operates between:
A. 10 to 350F
B. 25 to 250F
C. 140 to 350F
D. 280 to 350F
A. 10 to 350F
- CUI is a possibility on insulated austenitic 300 Series SS equipment that operates between:
A. 10 to 350F
B. 25 to 250F
C. 140 to 350F
D. 280 to 350F
C. 140 to 350F
- CUI is a possibility on insulated Duplex SS equipment that operates between:
A. 10 to 350F
B. 25 to 250F
C. 140 to 350F
D. 280 to 350F
D. 280 to 350F
- CUI is a possibility on insulated 400 Series SS equipment that operates between:
A. 10 to 350F
B. 25 to 250F
C. 140 to 350F
D. 280 to 350F
A. 10 to 350F
- CUI occurring on 300 Series and Duplex SS equipment is actually caused by what type of corrosion mechanism?
A. Amine Cracking
B. Chloride SCC
C. Fiber fretting
D. Galvanic corrosion
B. Chloride SCC
- CUI is an inspection concern for insulated vessel that operates at 500F and:
A. is in an intermittent service
B. is made of stainless steel
C. is made of low chromes
D. have poorly maintained insulation
A. is in an intermittent service
- Which of the following insulated equipment is most likely to experience CUI?
A. CS vessel that operates continuously at 375F
B. CS vessel that operates continuously at -20 F
C. CS vessel with with operating temp of 600F but it is in an intermittent service
D. CS vessel that operates at cyclic temperatures ranging between 375F-600F
E. 300 SS vessel that operates continuously at 100F
C. CS vessel with with operating temp of 600F but it is in an intermittent service
- CUI can be more aggressive when:
A. The temperature is lowered.
B. Using fiberglass insulation
C. the insulation sheathing is made from aluminum
D. chlorides leach out of the insulation
D. chlorides leach out of the insulation
- Which of the following is NOT a common location for CUI on piping?
A. bolted on pipe shoes
B. First few feet of horizontal pipe attached to a bottom of a vertical pipe run
C. Insulation terminations
D. Piping spec breaks
E. Steam tracing tubing penetrations
D. Piping spec breaks
- Which of the following is a common location of CUI on piping? *This may have more than one correct answer, please select all answers that apply
A. vibrating piping systems
B. piping with insulation jacket seams on top of line
C. above insulation support rings on vertical vessels
D. piping or equipment near a cooling water tower
E. 300 series SS with fiberglass insulation
A. vibrating piping systems
B. piping with insulation jacket seams on top of line
C. above insulation support rings on vertical vessels
D. piping or equipment near a cooling water tower
- Which type of older insulation has been known to contain a high level of chlorides?
A. Asbestos
B. Calcium silicate
C. Fiberglass
D. Mineral wool
B. Calcium silicate
- CUI on Carbon Steel or low-alloy materials can appear as:
A. Cracking
B. general wall loss
C. localized wall loss
D. localized pitting or localized wall loss
D. localized pitting or localized wall loss
- CUI on 300 Series SS materials can appear as:
A. Cracking
B. general wall loss
C. localized pitted or localized wall loss
D. cracking or pitting
D. cracking or pitting
- What causes the CUI cracking on 300 Series SS materials?
A. Chlorides
B. Hydrogen
C. Nitrates
D. Sulfates
E. Kryptonite
A. Chlorides
- Which of the following is the best method to prevent CUI?
A. Flame sprayed platinum coatings
B. Apply appropriate coating prior to insulating
C. Use of closed-cell foam glass insulations
D. Wishful thinking
B. Apply appropriate coating prior to insulating
- What type of flame-sprayed coating has been successfully used to prevent CUI on carbon steel equipment?
A. Aluminum coating
B. Chrome coating
C. Lead coating
D. Nickel coating
A. Aluminum coating
- Which type of insulation dries quicker, thus lowering the rate of CUI?
A. Bonded-cell insulation
B. Closed-cell insulation
C. No cell-insulation
D. Open-cell insulation
D. Open-cell insulation
- What document was created specifically to address corrosion under insulation and corrosion under fire proofing?
A. API 583
B. API 598
C. ASME PCC-2
D. ASTM 370
E. NACE 1105-02
A. API 583
- Which of the following is a very good method for inspecting for CUI damage?
A. De-insulate & Visual Inspection
B. MFL
C. MT
D. Neutron backscatter
A. De-insulate & Visual Inspection
- Without having to remove the insulation, which of the following is a method to determine the amount of CUI damage? This may have more than one correct answer, please select all answers that apply
A. ECT (eddy current testing)
B. GWT (guided-wave testing)
C. Neutron backscatter
D. PEC (pulsed eddy current)
E. Real-time profile RT
B. GWT (guided-wave testing)
D. PEC (pulsed eddy current)
E. Real-time profile RT
- Which of the following is an NDE method to find areas of wet insulation? This may have more than one correct answer, please select all answers that apply
A. ECT
B. MFL
C. Infrared thermography
D. Neutron backscatter
E. Real-time profile RT
C. Infrared thermography
D. Neutron backscatter
