Examen de Evaluación API 5711.-A sudden rapid fracture under stress (residual or aplied) where the material exhibits little or no evidence of ductibility or plastic deformation is called :

Decarburization fracture.

Temper embrittlement.

Glass like failure.

Brittle fracture.2.-Three of the steels listed below are susceptible to brittle fracture. Pick the one that is not.

carbon steel.

300 series of stainless steels.

Low alloy steel.

400 series of stainless steels.3.-Three factors when critically combined tend to cause brittle fracture.Which of the four factors listed below does not belong?

The material s fracture toughness(resistant to crack like flaws)is low.

The size, shape and stress concentration of a flaw tends to lead to failure.

The temperature is high enough to induce failure .

The amount of residual and applied stresses in the flaw is enough to cause fracture.4.-In most cases,brittle fracture occurs only at temperatures below the Charpy impact___________ tempetature,the point at which the toughness of the material drops off sharply.

Failure

Transition

Critical

Stable5.-What year did the ASME Boiler and Pressure Vessel Code,Section VIII, Division 1 begin to requiere toughness as a criteria for vessels operating at cold temperatures?

1987

1942

1995

19636.-Brittle fracture can occur during ambient temperature during a hydro-test due to:

Unusual loading and high toughness at the testing temperature.

High impact stresses and plasticity at the testing temperature.

High stresses and low toughness at the testing temperature.

High strength material and temperatures below 100 degrees F.7.-How do you mitigate brittle fracture of new equipment.

Use only 400 series stainless steels.

Use only 300 series stainless steels.Use material specifically designed for low temperature operation per ASME B&PV Code.Use material designed for high temperature operation per ASME B&PV Code.

8.-Thermal fatique is the result of _____ _____ caused by variations in temperature.

Torsional stresses

Tensile stresses

Cyclic stresses

Bending stresses9.-What type damage is caused by thermal fatigue?

Damage is in the form of severe oxidation and scaling.

Damage is in the form of cracking anywhere a movement or expansion is constrained.

Damage is in the form of tensile separation of high stressed parts of equipment.

Damage is in the form of bending of parts that are highly stressed.10.-What materials are affected by thermal fatigue?

Carbon steel.

All materials of construction.

Low alloy steel.

400 series of stainless steels.11.-Key factors affecting thermal fatique are the magnitude of the __________ ________ and the (_________ _____ ________)

Temperature;rate(speed of rise)

Equipment size:complexity(intricacy of construction)

Stress loading;size(increase,decrease of loads)

Temperature swing;frequency(number of cycles)12.-Thermal fatigue cracking has been a major problem in:

Depropanizer vessels.

Coke drum shells.

Boiler feed water tanks.

Catalyst storage drums.13.-Thermal fatigue is best prevented through ________to minimize thermal stresses and thermal cycling.

Selection of materials.

Prevention of movement

Design and operation

Allowance of travel14.-Since cracking is usyally surface connected,effective methods of inspection are:

WFMT and LT.

ET,and AE.

VT,MT and PT.

AET,ET,and RT15.-Accelerated mechanical removal of surface material as a result of relative movement between,or impact from solids,liquids,vapor or any combination there of is known as:

Weathering.

Corrosion.

Erosion.

Attrition.16.-A description of the damage that occurs when corrosion contributes to erosion by removing protective films or scales,or by exposing the metal surface to further corrosion under the combined action of erosion and corrosion is called:

Surface weathering.

Erosion-attrition.

Erosion-corrosion.

Abrasion-wear17.-Equipment that is exposed to moving fluids and/or catalyst particles?

Desalting Unit.

Motor Oil Unit.

Crude and Vacuum Unit.

Fluid Catalytic Cracker.

18.-What type of unit suffers severe erosion-corrosion due to exposure to naphthenic acids in some crude oil?

Catalytic Reformer Reactor piping.

FCCU Fractionator overhead lines.

Hydroprocessing effluent piping.

Crude and Vaccum unit piping and vessels.19.-Pits,grooves,gullies,waves,rounded hoteles & valleys exhibiting a directional pattern are characteristics of:

Abrasion and abrasion wear.

Erosion and erosion.corrosion.

Surface weathering.

Scuffing and scraping20.-Erosion-corrosion is best controlled by using________ and/or altering the process environment to reduce corrsivity.

Corrosion inhibitors

Wear plates

Hard-facing by weld overlays

More corrosion-resistant alloys21.-What type of material offers improved resistance to naphthenic acid corrosion?

Higher chrome containing alloys.

Higher nickel containing alloys.

Higher molybdenum containing alloys.

Higher colombium containing alloys.22.-Insepection methods for detecting the extent of metal loss due to erosion and erosion-corrosion are:

AE,MT and ET

VT,UT, and RT.

PT,ET, and AETLT,ET, and WFMT

23.-What type of on stream inspection method can detect the loss of refractory on an operating unit?

Visual inspection .

Infrared scan.

Ultrasonic scan.

Eddy current scan.24.-What is the typical erosion.corrosion rate in mpy of Monel immersed in seawater flume with the seawater traveling over it at 4 fps?

0.2mpy

< 0.2 mpy

1mpy

0.3 mpy25.-What types of material are affected by mechanical fatigue cracking?

300 and 400 series stainless steels are affected.

Only carbon steel is affected.

All engineering alloys are affected.

Monel and cooper containing metals are affected.26.-Three types of equipment with mechanical loading that are affected by mechanical fatigue cracking are listed below.One of the four items listed below is not correct.Pick the incorrect item.

Rotating shafts on centrifugal pumps that have stress concentrations due to key ways.

Small diameter piping that vibrates because of adjacent equipment.

Large,heavy,cast steel compressor cases.High pressure drop control valves or steam reducing stations that have serious vibration problems.

27.-A fatigue failure exhibits what type of "fingerprint" or appearance?

The failure exhibits a hash mark type of fingerprint that radiates from the crack origin.The failure exhibits a "clam shell" type of fingerprint that has concentric rings called "beach marks".The failure exhibits a wavy type of fingerprint that is random in nature.The failure exhibits a regged rough type of fingerprint that emanates from the failure point.

28.-The best defense against mechanical fatigue cracking is __________ which helps minimize stress concentration of components that are in cyclic service.

A material selection

Good design

The use of the thinnest material available

Good operations29.-NDE techniques such as______ ______and________ can be used to defect fatigue cracks at known areas of stress concetration

ET,AE,LT,

PT,MT,SWUT,

AET,WFMT,RFEC

RT,PMI,FMR30.-In what type of environment would atmospheric corrosion be most severe?

Marine environments, and moist polluted industrial environments.

Desert environments, and cold dry environments.

Areas exposed to the moring sun and prevailing winds.

Far north environments with maximium exposure to cold and snow.31.-What materials are affected most by atmospheric corrosion be most severe?

Nickel 200,Inconel,and Incoloy.

Monel,Titanium,Duranickel ALLOY 301.

300 series stainless steels,and cast iron.

Carbon steel ,low alloy steels, and alloyed aluminum32.-If a bere carbon steel line is located next to cooling tower with mist from the tower on the line, what would you expect to happen is the pipe is only protected by pooorly coated aluminum paint?

Severe external oxidation due to atmospheric conditions.

The paint will protect the line and no corrosion will occur.

Minor atmospheric corrosion could be expected.

Nothing will happen. The conditions for corrosion are not present.33.-How many mils per year would you expect a carbon steel line to lose if exposed to marine environment?

20 mpy

15 mpy

10 mpy

5 mpy34.-What is the atmospheric corrosion rate if carbon steel is exposed in a dry rural environment?

<4 mpy

<3 mpy

<2 mpy

<1 mpy

35.-In atmospheric corrosion, what naturally occurring substance if it gets on equipment will cause accelerated corrosion and stains?

Rain.

Bird feces.

Snow.

Dust.36.-What can prevent atmospheric corrosion?

Build plants in dry rural areas.

Surface preparation and proper coatings applied correctly.

Use stainless steel equipment.

Coat all surfaces exposed to the atmosphere with automobile undercoating.37.-What inspection methods are used for inspection and monitoring atmospheric corrosion?

AE and RT

PT and WFMT

ET and MT

VT and UT38.-Whate is the cause of corrosion under insulation (CUI) of refinery and chemical plant equipment?

The corrosion is caused by not having an on-going ando complete inspection program.

The corrosion is caused by long term lack of maintenance.

The corrosion is caused from the use of the wrong material for the equipment.

The corrosion resultsfrom water trapped under insulation and fireproofing.39.-What materials are usually affected by CUI?

Cast iron, Nickel 200,and aluminum.

Titanium,Duranickel alloy 301,and Copper nickel.

Monel,incoloy,and inconel.

Carbon steel ,low alloy steels, 300 series and duplez stainless steels.40.-What temperatures cause CUI to be most severe?

Between 100°F and 150°F

Between 212°F and 250°F

Between 100°F and 212°F

Between 250°F and 300°F

41.-An inspector notes that there are cracks in the brick fireproofing of a column supporting a vessel on a FCC unit. A inspection hole is opened to check the condition of the column.Heavy rust scale is present and inspector requieres the entire column to be

Heavy erosion from catalyst.

Chloride attck.

Normal weathering of the column.

CUI(corrosion under insulation)42.-If insulation has chlorides in it cause CUI related to stress corrosion cracking, what type material for equipment would be the most susceptible to demage?

400 series of stainless steels.

300 series of stainless steels.

Carbon of stainless steels.

Duplex stainless steels.43.-Three of the four items listed below are locations where CUI may be a problem. Which one of the four items would not be of concern?

Insulated piping operating at 350 °F.

Areas with demaged insulation.

Insulated equipment down-wind from cooling towers.

Equipment with leaking steam tracing.44.-A small pressure vessel made of 316 stainless steel is to be insulated. It operates at 220 °F in an area subject to a lot of of water vapor. The inspector checks the insulation that is to be used and finds that is contains chlorides. What should he do?

Stop the installation of the insulation that is to and make arrangements to have low/no chloride insulation installed.Make sure the area is covered during the installation of the insulation to avoid moisture being trapped.Nothing is required-the insulation is satisfactory.

Heat the vassel to 300°F during the installation of the insulation.45.-If wet insulation is suspected on a vassel or if damaged and missing insulation is suspected beneath an aluminum jacket on a vassel, what inspection method would be best to find the locations?

Strip the insulation completely and renew it.

Infrared thermography.

Radiograph the equipment.

Magnetic flux leakage.46.-What usually causes corrosion in boiler feedwater and condensate return systems?

Corrosion pitting is the result of dezincification of the tubes.

Corrosion is the result of dissolved heavy water (D20) and carbon monoxide (CO).

Corrosion is the result of HCl and H2SO4 inthe system.

Corrosion is the result of dissolved gases, oxygen and carbon dioxide.47.-What type of corrosion usually attributed to oxygen in boiler water condensate corrosion?

Pitting.

Smooth general corrosion.

Rough uneven corrosion.

Corrosion at weld HAZ s.48.-Smooth grooving of pipe walls is in and indication that__________ is the causative agent.

Carbon monoxide

Oxygen

Carbon dioxide

Hydrochloric or sulfuric acids49.-Deaerator cracking problems are usually evaluated off-line at shutdowns of boilers. What inspection method is used?

Radiographic inspection.

Wet fluorescense magnetic particle inspection.

Dye penetrant inspection.

Eddy current inspection.50.-Sulfur compounds reacter with carbon steel in high temperature environments. This reaction causes corrosion. The presence of___________ accelerates the corrosion.

Water

Carbon dioxide

Oxygen

Hydrogen51.-Copper base alloys form sulfide at ______ ________that carbon steel.

Faster rates

Lower temperatures

Slower rates

Higher temperatures52.-Major factors affecting sulfidation are alloy composition, temperature and concentration of corrosive__________ compounds.

Water

Hydrogen

Sulfur

Ammonia53.-What determines the susceptibility of an sulfidation?

Its ability to form protective sulfide scales.

The amount of nickel present.

The ability to resist erosion.

The capability to avoid graphitic descomposition.54.-Sulfidation of iron-based alloys usually begins at metal temperatures above____________.

800°F

700°F

600°F

500°F55.-What alloying element determines the resistance of an alloy to sulfidation?

Nickel.

Chrome.

Low carbon.

Columbium.56.-Depending on condition of service, sulfidation corrosion is most often in the form of:

Random grooving.

Uniform thinning

Heavy localized pitting.

Unsystematic pitting.57.-You may achieve resistance to sulfidation by:

Using an alloy containing columbium.

Employing carbon steel alloyed with silicon.

Upgrading to a hogher chromium alloy.

Using a 70-30 copeer-nickel alloy.58.-To monitor equipment for sulfidation corrosion, the process conditions should be observed for increasing temperatures and/or changing sulfur levels. How can you best monitor the temperature of the equipment that is subject to sulfidation corrosion?

Use an experienced inspector who can visually watch for changing temperature.Depend upon the operators to watch for any changes in operations and inform the inspectors.Use tube skin thermocouples and/or infrared thermo graphy.

Employ temperature indicating crayons to check for changing temperature.59.-Chloride stress corrosion cracking (CI SCC) is surface initiated cracks found in:

Carbon steel.

Low chrome alloy steel.

300 series SS and some nickel base alloys.

Nickel base alloys.60.-The Cl SCC surface cracks appear under the action of__________, temperature and an aqueous chloride environment.

Stagnant conditions

High velocity products

Compressive stress

Tensile strees61.-The presence of what other element increases the propensity for Cl SCC cracking?

Carbon dioxide.

Oxygen

Carbon monoxide.

Nitrogen62.-What percent of chloridesw is safe for exposure to 300 series stainless steel?

15%

10%

5%

0%63.-SCC usually occurs at pH values above:

5

4

3

264.-Stress corrosion cracking usually occurs at metal temperatures above about:

200°F

160°F

140°F

100°F65.-Nickel content of an alloy above_________percent makes it highly resistant to SCC.

10

25

35

1566.-What kind of steel is not susceptible to SCC?

AISI Type 347 SS.

AISI Type 316 SS.

Carbon steel.

Duplex SS.67.-Characteristic stress corrosion cracks have:

A generally random pattern and they do not join together.

Lightnung bolt appearance and are usually singular in nature.

Many branches and may be visually detectable by a craze-cracked appearance.

Few branches and are not visually detectable.68.-An inspector is preparing to hydrotest equipment that is made from AISI Type 304 stailess steel. One of the more important items that should be used is the:

Use of low oxygen content test water.

Use of low or no chloride water and dry out thoroughly and quickly.

Type of device to be used to pressure the system.

Kind of chemical to be placed in the water to retard effects of chlorides.69.-What is one of the preferred methods for finding SCC?

LT.

RT.

AE.

PT.70.-Caustic embrittlement is a from of___________characterizad by surface-initiated cracks that occur in piping and equipment exposed to caustic, primarily adjacent non-PWHT d welds.

Galvanic cracking

Stress corrosion cracking

Chloride cracking

Fatigue cracking71.-Primarily, where would you inspect for caustic embrittlement (caustic stress corrosion cracking)?

Examine the piping externally in long straight runs.

Look at areas covered by insulation.

Check the piping internally, away from welds.

Inspect next to non-PWHT d welds.72.-In caustic materials are affected by caustic embrittlement?

Monel and Inconel are susceptible to caustic embrittlement.

Carbon steel and 300 series SS are susceptible to caustic embrittlement.

Titanium and Nickel 200 are susceptible to caustic embrittlement.

Incoloy and Nickel alloys are susceptible to caustic embrittlement.73.-In caustic embrittlement, what two conditions, if changed, will promote more server cracking?

Change the location frome inside to outside and decrease thetemperature.

Decrease the temperature and the caustic concentration.

Increase the temperature and the caustic concentration.

Subject the equipment to more exposure to water and increase the stress level.74.-Caustic stress corrosion or caustic embrittlement typically propagates__________ to the weld in adjacent base metal but can also occur in the weld deposit or heat affected zones.

Perpendicular

Parallel

Vertical

At a 90 degree angle75.-Post weld stress heat treatment to stress realive the equipment can help effectively in preventing caustic embrittlement cracking of carbon steel.What temperature should be used for PWHT?

650°F

1550°F

1150°F

1450°F76.-An inspector call for low pressure steam out of equipment that has contained caustic in preparation for weld repairs. The inspector requieres that the equipment be washed thoroughly with clean water prior to steam out. What does this prevent?

Anime stress corrosion cracking.

Chloride cracking.

Caustic embrittlement cracking.

Carbolic acid environmental cracking.77.-What method NDE is not effective for finding cautic embrittlement cracking when it is tight & scale-filled?

RT.

VT.

PT.

WFMT.78.-What are two other similar forms of alkaline stress corrosion cracking mechanisms?

Anime and carbonate cracking.

Hydrogen and peroxide cracking.

Hyperchlorite and oxalic acid cracking.

Formic acid and glycerin cracking.79.-which cannot diffuse through the steel. The loss of__________ causes an overall loss of strength.

Carbide

Carbonate

Calcium

Iron80.-Which of the materials listed below are the least resistance to HTHA?

300 series stainless steel.

400 series stainless steel.

9Cr-1Mo.

Carbon steel.81.-Using the curves in Figure 5-35 of API RP 571, for a hydrogen partial pressure of 2500 psi, and temperature of 900 degrees F.,what material should be picked for use?

2.25Cr-0.5Mo.

3Cr-1Mo.

1.25Cr-0.5Mo.

Carbon steel.82.-Some units affected by HTHA are listed below. One of the ones listed is usually not considered a target. Pick this unit.

Hydrocracker.

Crude still.

Catalytic Reformer.

Hydrotreater.83.-Early stages of HTHA can only be confirmed through advanced:

Acoustic emissin testing.

Wet fluorescent magnetic particle testing.

ultrasonic techniques such as SWUT.

Metallographic analysis of damaged areas.84.-Cracking and fissuring caused by HTHA are_______ and occur adjacent to pearlite (iron carbide) areas in carbon steels.

Surface oriented

Subsurface

Laminations

Intergranular85.-When using the APIRP 941 curves for selecting an alloy steel for use, what increase in temperature is used as a safety factor?

10 to 20 degrees F.

75 to 100 degrees F.

100 to 200 degrees F.

25 to 50 degrees F.86.-What material has been removed from the Nelson curves shown in Figure 5-35 of API RP 571 and in API RP 941?

5Cr-0.5Mo

1Cr-0.5Mo

1.25Cr-0.5Mo.

C-0.5Mo

87.-Damage from HTHA occurs_________ in welds or weld heat affected zones as well as in the base metal.

Early

Randomly

Late

Occasionally88.-What is not a proven method for detection of HTHA demage?

VT.

AET.

WFMT.

RT.89.-Vibration induced fatigue is a form of_________.

SCC.

Mechanical fatigue.

Erosion.

Atmospheric corrosion.90.-Vibration induced fatigue affects what equipment?

Socket welds and small bore piping.

Flow loops.

Small branch connections with unsupported valves.

All the above.91.-Which are critical factors for vibration induced fatigue?

Amplitude of vibration.

Frequency of vibration.

Marine environment.

A &B above.92.-What determines the likelihood and severity of corrosion for flue gas dew point corrosion?

Concentration of sulfur and chlorides in the fuel.

An excess of vanadium in the fuel.

Condensation of hydrofluoric acid.

None of the above.93.-How do you prevent flue gas dew pont corrosion in boilers?

Add vanadium to thecfuel.

Burn low sulfur fuel.Maintain the metallic surfaces at the back end above the temperature of sulfuric acid dew point corrosion.Inject biocides into the flue gas.

94.-How do you monitor wastage of economizer tubes?

Use UT method for wall thickness measurement .

Perform random RT on tubes.

Use AE

Any of the above.95.-Where is MIC most often found?

In heat exchangers.

In piping in contact with some soils.

In piping with stagnant or low flow.

All the above.96.-How is the effectiveness of treatment monitored in cooling water systems?

Using AE

Measuring biocide residuals.

Using velocity ratio technique.

Using ACFM technique.97.-What is the appearance of MIC?

Localized pitting under deposits or tubercles.

Branching cracks.

transgranular cracks.

Step laminations.98.-Which of the following materials is affected by soil corrosion?

Series 300 SS.

Aluminum.

Carbon steel.

9 Cr- 1Mo99.-How should soil corrosion be monitored?

Taking UT measurements of the pipe.

Measuring the structure to soil potential.

Using profile radiography.

Visually