[Q19-Q41] 2026 Valid API-571 Dumps for Helping Passing API Exam!

QUESTION 19
(A metal cracks because of stress relaxation during postweld heat treatment (PWHT) of a heavy wall section.
This type of cracking is best categorized as:)

QUESTION 20
Dew point corrosion can occur if the metal temperature is below the dew point. The dew point of sulfuric acid is __________.

QUESTION 21
Which of the following damage mechanisms is related to steel hardness?

QUESTION 22
Amine cracking has been reported down to ambient temperatures with some amines. __________ temperatures and stress levels _______ the likelihood and severity of cracking.

QUESTION 23
Low creep ductility is _____ prevalent at the lower temperatures in the creep range. Or low stresses in the upper creep range.

QUESTION 24
For 5Cr-0.5Mo, what is the threshold temperature for creep?

QUESTION 25
Vibration-induced fatigue can be eliminated or reduced through _________ and the use of supports and vibration dampening equipment. Material upgrades are not usually a solution.

QUESTION 26
Which of the following is not a critical factor that contributes to a brittle fracture?

QUESTION 27
With steam blanketing, failure occurs as a result of _________ in the tube from the internal steam pressure at the elevated temperature.

QUESTION 28
Corrosion under insulation becomes more severe at metal temperatures between ________ and ________, where water is less likely to vaporize and insulation stays wet longer.

QUESTION 29
Stainless steels with sigma can normally withstand normal operating stresses but upon cooling to temperatures below _______ may show a complete lack of fracture toughness as measured by a Charpy impact test.

QUESTION 30
At high temperatures, metal components can slowly and continuously deform under load below the yield stress. This time dependent deformation of stressed components is known as __________.

QUESTION 31
(Caustic stress corrosion cracking can be effectively prevented by:)

QUESTION 32
_________ corrosion rates are found in a gas oil desulfurizers and hydrocrackers than naphtha desulfurizers and hydrocrackers by a factor of almost “2”.

QUESTION 33
SCC tendency ________ towards the alkaline pH region

QUESTION 34
(Creep damage can be mitigated by:)

QUESTION 35
With sulfuric acid corrosion, alloys such as Alloy 20 resist dilute acid corrosion and form a protective ________ film on the surface.

QUESTION 36
Many thermal fatigue cracks are filled with:

QUESTION 37
Which of the following is the lowest threshold temperature at which creep damage is a concern in carbon steel with tensile strength > 60ksi (414 MPa)?

QUESTION 38
Which of the following statements is most accurate with regard to thermal fatigue?

QUESTION 39
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?

QUESTION 40
_________ is most likely found in hard weld and heat-affected zones and in high strength components.

QUESTION 41
The presence of _________ can destabilize the scale and turn it into a nonprotective scale.