Question 1
Damage from sigma phase appears in the form of ________.
A. Corrosion
B. Hardness
C. Cracking
D. Ductility
Answer : C
Question 2
The presence of ________ in H²S streams increases the severity of high temperature sulfide corrosion at temperatures above about 500º F
A. Amine
B. Hydrogen
C. Sulfides
D. All of the above
Answer : B
Question 3
In vessels and piping, creep cracking can occur where high metal temperatures and
_________ occur together.
A. Pressures
B. Stress concentrations
C. Velocities
D. None of the above
Answer : B
Question 4
Many thermal fatigue cracks are filled with:
A. chlorides.
B. hydroslime.
C. oxides.
D. sulfides.
Answer : C
Question 5
_________ material sections also have a ___________ resistance to brittle fracture due to higher constraint, which increases triaxial stresses at the crack tip.
A. Thinner, Lower
B. Thicker, Lower
C. Thinner, Higher
D. Thicker, Higher
Answer : B
Question 6
Characteristic stress corrosion cracks have many branches and may be visually detectable by a __________ appearance on the surface.
A. Tree shaped
B. Craze-cracked
C. Multiple crack
D. None of the above
Answer : B
Question 7
Caustic embrittlement cracking can be effectively prevented by means of PWHT at a temperature of _______.
A. 1100º F
B. 1150º F
C. 1200º F
D. 1250º F
Answer : B
Question 8
Cavitation is a form of erosion caused by the formation and instantaneous collapse of innumerable tiny vapor bubbles. Temperatures approaching the boiling point of the liquid are _________ to result in bubble formation.
A. Less likely
B. More likely
C. Not likely
D. None of the above
Answer : B
Question 9
A 6, A106 Gr B, flanged line carrying caustic wash water at 200 F has signs of atmospheric corrosion. Which of the following may have help accelerate the corrosion?
A. Sulfides
B. Fly ash
C. Caustic
D. None of the above
Answer : B
Question 10
__________ is a change in the microstructure of steels after exposure in the 850 F to
1400 F range, where the carbide phases in carbon steels are unstable and may agglomerate from their normal plate-like appearance.
A. Carburization
B. Spheroidization
C. Graphiding
D. 885º Embrittlement
Answer : B
Question 11
__________ is a form of cracking that results when certain molten metals come in contact with specific alloys. Cracking can be very sudden and brittle in nature.
A. SCC
B. LME
C. AET
D. SOHIC
Answer : B
Question 12
With high temperature hydrogen attack, ________ using a combination of velocity ratio and backscatter have been the most successful in finding cracking.
A. MT
B. UT
C. RT
D. EC
Answer : B
Question 13
Which API RP recommends programs to monitor small-bore piping, flange faces, blistering and HIC/SOHIC in HF alky units?
A. 574
B. 751
C. 571
D. 980
Answer : B
Question 14
ASME Section VIII had few limitations concerning brittle fracture prior to:
A. 1955.
B. 1962.
C. 1973.
D. 1987.
Answer : D
Question 15
Refractory anchors must be resistant to __________ in high temperature services.
A. Thermal fatigue
B. Thermal cracking
C. Stress cracking
D. Oxidation
Answer : D
Question 16
HCL acid corrosion is found in several units, especially _______ and ________, units, hydroprocessing units and catalytic reformer units.
A. Amine, crude
B. Crude, Alkylation
C. Vacuum, Amine
D. Crude, Vacuum
Answer : D
Question 17
Which of these materials is not susceptible to amine cracking?
A. Carbon steel
B. 300 Series SS
C. 400 Series SS
D. Both B and C
Answer : D
Question 18
The best way to prevent 885 F embrittlement is to use low ________ alloys, or to avoid exposing the susceptible material to the embrittling range.
A. Austenite
B. Martensite
C. Ferrite
D. Chromium
Answer : C
Question 19
In most cases, brittle fracture occurs only at temperatures _________ the Charpy impact transition temperature.
A. Above
B. Below
C. Around
D. Inside
Answer : B
Question 20
With cooling water corrosion, _________ oxygen content tends to ________ carbon steel corrosion rates.
A. Increasing, increasing
B. Decreasing, decreasing
C. Decreasing, increasing
D. Increasing, decreasing
Answer : A
Question 21
With sulfuric acid corrosion, alloys such as Alloy 20 resist dilute acid corrosion and form a protective ________ film on the surface.
A. Sulfide
B. Chloride
C. Iron sulfate
D. Iron oxide
Answer : C
Question 22
Creep and stress rupture is more likely in a _________ grained material than a _______ grained material.
A. Course, Fine
B. Fine, Course
C. Austenetic, Martensitic
D. None of the above
Answer : A
Question 23
A hard, brittle surface layer will develop on some alloys due to exposure to high temperature process streams containing high levels of nitrogen compounds such as ammonia or cyanides, particularly under reducing conditions, is called _______.
A. Carburization
B. Spheroidization
C. Nitriding
D. None of the above
Answer : C
Question 24
If wet electrodes or high moisture content flux is used, ________ can be charged into the steel resulting in delayed cracking.
A. Atomic hydrogen
B. Hydrogen
C. Oxygen
D. H²O
Answer : B
Question 25
The severity of hydrochloric acid corrosion ________ with _________ HCl concentration and increasing temperatures.
A. Decreases, decreasing
B. Increases, increasing
C. Decreases, increasing
D. Increases, decreasing
Answer : B
Question 26
Oxygen and iron in the wash water injected into reactor effluent can lead to __________ corrosion and fouling.
A. Increased
B. Decreased
C. Substantial
D. Minimal
Answer : A
Question 27
What is the chemical symbol for ethane or ethylene?
A. C²
B. C3
C. C4
D. CH4
Answer : A
Question 28
If the BHN is 400-500 it may indicate __________.
A. Carburization
B. Hydriding
C. Temper embrittlement
D. Caustic embrittlement
Answer : B
Question 29
Although the loss of toughness from temper embrittlement is not evident at operating temperatures, equipment that is temper embrittled may be susceptible to ________ during start-up and shutdown.
A. Thermal fatigue
B. Cyclic stress
C. Notch toughness
D. Brittle fracture
Answer : D
Question 30
Heat treatment can have a significant effect on the toughness and hence fatigue resistance of a metal. In general, ________ grained microstructures tend to perform better than
_________ grained.
A. Fine, Course
B. Austenetic, martensitic
C. Course, Fine
D. Martensitic, austenetic
Answer : A
Question 31
With sulfidation, the presence of oxygen ________ corrosion
A. Increases
B. Decreases
C. Has no effect on
D. Stops
Answer : A
Question 32
The endurance limit is usually about:
A. 10-20% of a material’s ultimate tensile strength.
B. 40-50% of a material’s ultimate tensile strength
C. 10-20% of a material’s yield strength.
D. 40-50% of a material’s yield strength.
E. Half way up the ladder of a 150’ column (tower).
Answer : B
Question 33
A quick test for embrittlement from _________ is a bend test or crush test. Unaffected material will be crushed in a ductile fashion while embrittled components will crack with no signs of ductility.
A. Titanium Hydriding
B. Temper embrittlement
C. Caustic embrittlement
D. None of the above.
Answer : A
Question 34
Corrosion from oxygen tends to be __________ type damage and can show up anywhere even if only very small amounts break through the scavenging system.
A. General
B. Localized
C. Pitting
D. Cracking
Answer : C
Question 35
A fatigue fracture is brittle and the cracks are most often __________.
A. Parallel
B. Transgranular
C. Intergranular
D. Transverse
Answer : B
Question 36
Dissimilar weld metal cracking can be aggravated by _______.
A. Stress
B. Pressure
C. Thermal cycling
D. Cyclic stresses
Answer : C
Question 37
Time to failure by thermal fatigue is primarily affected by:
A. Magnitude of stress and operating temperature.
B. Magnitude of stress and number of cycles.
C. Carbon content in material and operating temperature.
D. Carbon content in material and number of cycles.
Answer : B
Question 38
______ is most likely found in hard welds and heat affected zones and in high strength components.
A. SOHIC
B. HIC
C. Carburization
D. SSC
Answer : D
Question 39
Which of the following materials is susceptible to CO² corrosion?
A. Carbon steel
B. Stainless steel
C. Duplex stainless steel
D. Both B and C
Answer : A
Question 40
Amine stress corrosion cracking is most often associated with lean amine services. The pure alkanolamine does not cause cracking. Cracking in rich amine services are most often associated with _______ problems.
A. H²S
B. Stress
C. Wet H²S
D. Temperature
Answer : C
Question 41
_________ is a change in the microstructure of certain carbon steels and 0.5Mo steels after long-term operation in the 800 F to 1100 F range that may cause a loss in strength, ductility and/or creep resistance.
A. Embrittlement
B. Carburization
C. Graphitization
D. Sensitization
Answer : C
Question 42
For furnaces, to prevent PASCC, keep the firebox heated above the dewpoint to keep
________ from forming.
A. Water
B. Acids
C. Moisture
D. Corrosion
Answer : B
Question 43
_______ is the primary alloying agent that affects resistance to oxidation.
A. Chromium
B. Molybdenum
C. Silicon
D. Aluminum
Answer : A
Question 44
At a given pressure, the HS concentration in the sour water _________ as temperature
_________.
A. Increases, increases
B. Decreases, decreases
C. Increases, decreases
D. Decreases, increases
Answer : D
Question 45
___________ is when oxygen reacts with carbon steel and other alloys at high temperatures converting the metal to oxide scale.
A. High temperature corrosion
B. Oxidation
C. Dealloying
D. Thermal fatigue
Answer : A
Question 46
_________ is most likely found in hard weld and heat-affected zones and in high strength components.
A. HIC
B. SSC
C. SOHIC
D. Blistering
Answer : B
Question 47
What method is most used to assure boiler feed water corrosion is not occurring?
A. Spot UT readings at turbulent areas
B. Profile RT at turbulent areas
C. Profile RT at stagnant areas
D. Laboratory analysis of boiler feedwater
Answer : D
Question 48
If wet electrodes or high moisture content flux weld electrodes are used to weld carbon steel, hydrogen can be charged into the steel resulting in _________.
A. Reduced tensile strength
B. Loss of ductility
C. Delayed cracking
D. All of the above
Answer : C
Question 49
_________ is the main concern during start-up, shutdown and/or hydro testing for equipment/piping operating at elevated temperatures. This event can also occur in an auto refrigeration event in units processing light hydrocarbons.
A. Stress fracture
B. Carburization
C. Spheroidization
D. Brittle fracture
Answer : D
Question 50
What standard refers to Fitness-For-Service evaluations?
A. RP 581
B. RP 579
C. RP 588
D. RP 568
Answer : B
Question 51
When carbon is absorbed into a material at elevated temperatures while in contact with a carbonaceous substance it is called carburization. Temperatures usually have to be above
__________ for this to occur.
A. 1000º F
B. 1100º F
C. 1200º F
D. 1400º F
Answer : B
Question 52
Reheat cracking is most frequently observed in _______ grained sections of a heat- affected zone.
A. Course
B. Fine
C. Dense
D. Treated
Answer : A
Question 53
Lean amine is generally not corrosive because they have either low conductivity and/or high pH. Corrosion rates increase with increasing temperatures, particularly in rich amine service. Temperatures above _________ can result in acid gas flashing and severe localized corrosion.
A. 170º F
B. 190º F
C. 220º F
D. 240º F
Answer : C
Question 54
Areas of vulnerability in sulfuric acid Alkylation units include reactor effluent lines, reboilers, deisobutanizer, overhead systems and the _________ treating system.
A. Caustic
B. Sulfuric acid
C. Catalyst
D. H²S
Answer : A
Question 55
Inspection for wet H2S damage generally focuses on _____ and ______.
A. Weld seams
B. Nozzles
C. Trays
D. Down comers
E. A and B
Answer : E
10 questions per page
Question 56
Amine cracking has been reported down to ambient temperatures with some amines.
__________ temperatures and stress levels _______ the likelihood and severity of cracking.
A. Increasing increases
B. Increasing, decreases
C. Decreasing increases
D. Increasing, reduces
Answer : A
Question 57
___________ is the result of cyclic stresses caused by variations in temperature.
A. Cyclic cracking
B. Stress cracking
C. Stress fatigue
D. Thermal fatigue
Answer : D
Question 58
Which of the following is not a primary initiating point for thermal fatigue?
A. Notches
B. Rounded pits
C. Nozzle-to-shell welds
D. Weld toes
Answer : B
Question 59
A brittle fracture:
A. Is caused by stress cycles.
B. Is always the result of thermal stresses.
C. Grow very rapidly with minimum deformation prior to failure.
D. Grows slowly and is dependent on time and stress.
Answer : C
Question 60
____________ is the reduction in toughness due to a metallurgical change that can occur in some low alloy steels as a result of long-term exposure in the temperature range of about 650 F to 1100 F.
A. Hardening
B. Graphitization
C. Spheroidization
D. Temper embrittlement
Answer : D
Question 61
_________ corrosion rates are found in a gas oil desulfurizers and hydrocrackers than naphtha desulfurizers and hydrocrackers by a factor of almost 2.
A. Lower
B. Higher
C. Sulfidization
D. Hydrogen corrosion
Answer : B
Question 62
Convert these temperatures – 156º C and 450º F
A. 304º F, 151º C
B. 284º F, 218º C
C. 312º F, 232º C
D. 296º F, 246º C
Answer : C
Question 63
300 Series SS is susceptible to LME when it comes in contact with molten ________.
A. Cadmium
B. Mercury
C. Zinc
D. Lead
Answer : C
Question 64
In fired heater tubes, dissimilar weld metal cracking forms primarily on the _______ of the material.
A. Outside
B. Inside
C. Welds
D. All of the above
Answer : A
Question 65
A form of mechanical fatigue in which cracks are produced as a result of dynamic loadings is _______.
A. Spheroidization
B. Vibration-induced cracking
C. Fatigue cracking
D. Stress cracking
Answer : B
Question 66
The creep threshold temperature for 1 ¼, 2 ¼, 5 and 9 Cr is ________.
A. 600º F
B. 700º F
C. 800º F
D. 1000º F
Answer : C
Question 67
Thermal fatigue damage is in the form of cracking that may occur anywhere in a metallic component where relative movement is constrained, particularly under repeated
__________.
A. Cyclic stresses
B. Thermal cycling
C. Pressure variations
D. All of the above
Answer : B
Question 68
With sour water corrosion, at a given pressure, the HS concentration in the sour water
_________ as temperatures ________.
A. Increases, increases
B. Decreases, decreases
C. Increases, decreases
D. Decreases, increases
Answer : D
Question 69
Mitigation of CUI is best achieved by _________.
A. A properly documented inspection program
B. A properly installed insulation system
C. A properly applied coating system
D. A properly documented NDE program
Answer : C
Question 70
Carburization can be confirmed by a substantial increase in hardness and a _______ in ductility.
A. Loss
B. Gain
C. Change
D. None of the above
Answer : A
Question 71
The best method to inspect for SCC is ____.
A. WFMT
B. UT Shear wave
C. AET
D. All of the above
Answer : A
Question 72
Which of the following materials are subject to mechanical fatigue?
A. Carbon steels
B. Stainless steels
C. Low alloy steels
D. All of the above
Answer : D
Question 73
____________ is a form of environmental cracking that can initiate on the surface of high strength low alloy steels and carbon steels with highly localized zones of high hardness in the weld metal and HAZ as a result of exposure to aqueous HF acid service.
A. Sulfide stress cracking
B. Hydrogen stress cracking
C. Caustic stress cracking
D. Hydrogen induced cracking
Answer : B
Question 74
Hydrogen stress cracking is the same mechanism that is responsible for sulfide stress corrosion cracking in wet HS environments except that HF acid is generating the
__________.
A. Sulfide
B. Caustic
C. Hydrogen
D. Water
Answer : C
Question 75
What treatment is used to prevent boiler feed water corrosion?
A. Oxide scavengers are added to process
B. Oxygen scavengers are added to process
C. Sulfide scavengers are added to process
D. Sulfur scavengers are added to process
Answer : B
Question 76
Steam blanketing is when the heat flow balance is disturbed; individual bubbles join to form a steam blanket, a condition known as Departure from Nucleate Boiling (DNB). Once a steam blanket forms, tube rupture can occur rapidly, as a result of _________.
A. Thermal fatigue
B. Short term overheating
C. Brittle fracture
D. Stress
Answer : B
Question 77
Cooling water corrosion can result in many different forms of damage including general corrosion, pitting corrosion, ________, stress corrosion cracking and fouling.
A. MIC
B. HIC
C. SOHIC
D. All of the above
Answer : A
Question 78
In order to minimize and prevent amine SCC, PWHT all carbon steel welds in accordance with API RP _____.
A. 751
B. 912
C. 510
D. 945
Answer : D
Question 79
In a pump, the difference between the actual pressure, or head, of a liquid available
(measured on the suction side) and the vapor pressure of that liquid is called Net Positive
Suction Head (NPSH) available. The minimum head required to prevent cavitation with a given liquid at a given flow rate is called Net Positive Suction Head __________.
Inadequate NPSH can result in cavitation.
A. Surplus
B. Required
C. Reserve
D. None of the above
Answer : B
Question 80
__________ is a form of damage found mostly in older vintage carbon steels and C-0.5 Mo low alloy steels under the combined effects of deformation and aging at an intermediate temperature.
A. Spheroidization
B. Thermal fatigue
C. Strain aging
D. None of the above
Answer : C
Question 81
The level of creep damage is a function of the material and the coincident _________ level at which the creep deformation occurs.
A. Pressure/Temperature
B. Pressure/Stress
C. Temperature/Stress
D. None of the above
Answer : C
Question 82
Sensitization occurs in the _____ to _______ range.
A. 800º F, 1400º F
B. 750º F, 1500º F
C. 600º F, 1120º F
D. 1000º F, 1750º F
Answer : B
Question 83
Changing to a more corrosion resistant and/or higher hardness material _________ improve cavitation resistance.
A. Will
B. May
C. Will not
D. May not
Answer : D
Question 84
For carbon steel, common velocity limits are generally limited to _________ fps for rich amine and _______ fps for lean amine.
A. 8-10, 30
B. 6-9, 15
C. 4-8, 10
D. 3-6, 20
Answer : D
Question 85
Stress levels and __________ are the critical factors causing carbonate stress corrosion cracking.
A. Temperature
B. Velocity
C. Water chemistry
D. None of the above
Answer : C
Question 86
Corrosion protection in the boiler is accomplished by laying down and continuously maintaining a layer of _____.
A. Manganese
B. Magnetite
C. Carbon monoxide
D. Carbonate
Answer : B
Question 87
For galvanic corrosion to take place, three conditions must be met, presence of an electrolyte, two different materials or alloys and ___________.
A. A cathode
B. An anode
C. An electrical connection
D. None of the above
Answer : C
Question 88
Corrosion under insulation becomes more severe at metal temperatures between
________ and ________, where water is less likely to vaporize and insulation stays wet longer.
A. 100º C, 121º C
B. 92º C, 116º C
C. 114º C, 132º C
D. None of the above
Answer : A
Question 89
Soil corrosion of carbon steel can be minimized through the use of special backfill, coatings and _______.
A. Cathodic protection
B. Resistivity
C. Temperature
D. None of the above
Answer : A
Question 90
Corrosion due to acidic sour water containing HS at a pH between 4.5 and 7.0 is called sour water corrosion. Carbon dioxide (CO) may also be present. Which of the following materials is susceptible to sour water corrosion?
A. Carbon steel
B. 300 Series SS
C. 400 Series SS
D. Both B and C
Answer : A
Question 91
For a specific material, HTHA is dependent on temperature, hydrogen partial pressure, time and _________.
A. Stress
B. Pressure
C. Velocity
D. Alloy composition
Answer : A
Question 92
300 series stainless steel heater tubes in an oil-burning furnace in the hydrocracker began to leak and the furnace was brought down. What was the probable cause of the cracking?
A. Chloride stress corrosion
B. Polythionic acid stress corrosion
C. Amine stress corrosion
D. Stress oriented hydrogen induced cracking
Answer : B
Question 93
__________ are the most common type of equipment susceptible to carburization in the refining industry.
A. Reactors
B. Heat exchangers
C. Heater tubes
D. Fin Fans
Answer : C
Question 94
Components that have been carburized may have a change in the level of ________.
A. Carbon
B. Chromium
C. Ferromagnetism
D. Stress
Answer : C
Question 95
________ eliminates the susceptibility of most common steels to SCC.
A. Preheat
B. High temperature
C. PWHT
D. All of the above
Answer : C
Question 96
Primarily hot-wall piping and equipment in the following units can be affected by graphitization. FCC, catalytic reformer and ______.
A. Hydrotreater
B. Hydrocracker
C. Coker
D. Alky
Answer : C
Question 97
What test is used to determine a material’s toughness?
A. Charpy impact test
B. Guided bend test
C. Metallography
D. Tension test
E. Physical fitness test
Answer : A
Question 98
__________ is usually found in aqueous environments or services where water is sometimes or always present, especially where stagnant or low-flow conditions allow the growth of microorganisms.
A. MIC
B. HIC
C. SOHIC
D. None of the above
Answer : A
Question 99
With Cl SCC, ________ levels of chloride ________ the likelihood of cracking.
A. Decreasing, Increases
B. Increasing, Decreases
C. Increasing, Increases
D. Increasing, Eliminates
Answer : C
Question 100
Geometry, stress level, number of cycles and _________ are the predominate factors in determining the fatigue resistance of a component.
A. Temperature
B. Material properties
C. Pressure
D. Velocity
Answer : B
Question 101
Inspecting for high-cycle fatigue can be difficult since:
A. The cracks are extremely tight.
B. Predicting the location of cracking is difficult.
C. Once the crack begins, only a few cycles are needed for the crack to lead to failure.
D. Often the equipment is vibrating making non-destructive evaluations difficult.
Answer : C
Question 102
A condition where steel loses strength due to the removal of carbon and carbides leaving only an iron matrix is called decarburization. This occurs during high temperatures, during
PWHT and from exposure to fires. Which of the following materials is not affected by this?
A. Low alloy steel
B. Duplex SS
C. Carbon steel
D. None of the above
Answer : B
Question 103
With hydrofluoric acid corrosion, corrosion rates increase with _______ temperatures and
______ HF concentrations.
A. Increasing, decreasing
B. Decreasing, increasing
C. Increasing, increasing
D. Decreasing, decreasing
Answer : A
Question 104
Increasing the chromium in steels offers no major improvement in resistance to CO corrosion until a minimum of __________ is reached.
A. 9%
B. 12%
C. 5%
D. 7%
Answer : B
Question 105
Hydrogen blisters may form at many different depths from the surface of the steel, in the middle of the plate or near a weld. In some cases, neighboring or adjacent blisters that are at slightly different depths (planes) may develop cracks that link them together.
Interconnecting cracks between the blisters often have a __________ appearance.
A. Crescent
B. Eyebrow
C. Step like
D. Jagged
Answer : C
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