Free Preparation Discussions
MENU
API-571 Exam Questions
- Topic 1: Terms, Definitions, and Acronyms: This domain covers the key terminology, standard definitions, and commonly used acronyms related to corrosion and materials. It ensures a clear understanding of technical language used throughout the API-571 body of knowledge.
- Topic 2: Damage Mechanisms: This domain explains various corrosion and damage mechanisms, including their characteristics, affected materials, causes, and visual appearance. It also covers where damage occurs, along with methods for prevention, mitigation, inspection, and monitoring.
Free API API-571 Exam Actual Questions
Note: Premium Questions for API-571 were last updated On Oct. 08, 2026 (see below)
(Grooving in cooling water tubes could be due to:)
Comprehensive and Detailed Explanation From Exact Extract:
Grooving corrosion in cooling water systems is a well-documented damage mechanism in API RP 571, particularly associated with high-velocity flow conditions.
Flow-induced erosion (also referred to as erosion-corrosion or flow-assisted corrosion) occurs when:
High fluid velocity removes protective corrosion films
Local turbulence, elbows, or inlet zones focus mechanical wear
Soft metals or alloys are exposed to continuous impingement
This results in smooth, directional grooves or channels aligned with the flow direction, a classic signature described in API RP 571.
Why the other options are incorrect:
Option A: ERW defects affect weld seams, not general grooving patterns.
Option B: MIC typically causes localized pitting, not uniform grooving.
Option D: Underdeposit corrosion produces irregular pitting beneath deposits, not flow-aligned grooves.
API RP 571 specifically identifies flow-induced erosion as a primary cause of grooving in cooling water heat exchanger tubes.
Referenced Documents (Study Basis):
API RP 571 -- Section on Erosion/Erosion-Corrosion
API Cooling Water System Corrosion Study Guide
Short-term stress rupture is a/an:
From API RP 571 Section 5.3.2.1 (Creep and Stress Rupture):
''Short-term creep rupture is often associated with localized overheating and results in bulging and thinning, often with a characteristic 'fish-mouth' rupture appearance. These failures occur under sustained load in a short time (hours or days), typically in high-temperature service due to a sudden increase in temperature or poor heat distribution.''
Thus, Option B accurately describes the mechanism and visual indications of short-term stress rupture.
Which type of corrosion is most likely to occur in hydroprocess reactor effluent streams in units producing alkaline sour water?
From API RP 571 and RP 932-B:
''In hydroprocessing reactor effluent systems, the most common corrosion mechanism is ammonium bisulfide (NHHS) corrosion, which forms in the presence of hydrogen sulfide and ammonia.''
''NHHS attacks carbon steel aggressively under turbulent flow and at low pH.''
Correct answer is B -- ammonium bisulfide corrosion.
Nitriding of steels becomes most severe at temperatures above:
API RP 571 under Nitriding (Section 4.2.16):
''Nitriding occurs at elevated temperatures and is most severe at temperatures above 900F (480C).''
''This mechanism is associated with the reaction of ammonia or other nitrogen-containing compounds with the steel surface, leading to brittle nitride formation.''
Therefore, the correct answer is D.
Which of the following weldments is most susceptible to dissimilar metal cracking when operating at high temperatures?
Dissimilar Metal Cracking (DMC) is a form of high-temperature cracking that frequently occurs in weld joints between carbon steel and austenitic stainless steel (such as Type 316 SS) due to differences in thermal expansion coefficients and mechanical properties.
From API RP 571 Section 5.2.3.1 (Dissimilar Metal Weld Cracking):
''Cracking frequently occurs in weld joints between ferritic and austenitic materials such as carbon steel to 300 series stainless steels due to thermal expansion mismatch during high temperature operation.''
Therefore, Option D (Carbon steel to 316 stainless steel) is the most susceptible combination and the correct answer.
- Select Question Types you want
- Set your Desired Pass Percentage
- Allocate Time (Hours : Minutes)
- Create Multiple Practice tests with Limited Questions
- Customer Support
Olivia Clark
19 days agoElizabeth Smith
1 month agoKevin Baker
2 months agoJoseph White
2 months agoElizabeth Martinez
3 months agoStephen Collins
3 months agoGary Harris
4 months agoElizabeth Mitchell
4 months agoDaniel Reed
5 months agoAmy Rivera
5 months agoDeborah Moore
6 months agoMonica Bailey
5 months agoJessica Turner
5 months agoChristopher Robinson
6 months agoSusan Phillips
5 months agoDonald Cooper
6 months agoBrigette
6 months agoFlo
6 months agoAsuncion
7 months agoRaul
7 months agoDelfina
7 months agoPamella
7 months agoRozella
8 months agoJennie
8 months agoAlfreda
8 months agoJesusita
8 months agoEmily
9 months agoAfton
9 months agoJina
9 months agoRessie
9 months agoLisandra
10 months agoVeronica
10 months agoAnnett
10 months agoArletta
10 months agoLou
11 months agoAntonio
11 months agoEarnestine
11 months agoAshley
11 months agoPaulene
12 months agoRyan
12 months agoLinn
1 year agoJosphine
1 year agoJose
1 year agoDominga
1 year agoIsidra
1 year agoGrover
1 year agoJessenia
1 year agoNorah
2 years agoMicah
2 years agoHerminia
2 years agoSanda
2 years agoWillard
2 years agoRicki
2 years agoKenia
2 years agoRessie
2 years agoWilletta
2 years agoMarjory
2 years agoMari
2 years agoAron
2 years agoCarri
2 years agoFranchesca
2 years agoDenny
2 years agoGeorgeanna
2 years agoBrandon
2 years agoTheresia
2 years agoLayla
2 years agoRozella
2 years agoPaulina
2 years agoMan
2 years agoEun
2 years agoLashon
2 years agoHoa
2 years agoSheridan
2 years agoNorah
2 years agoSina
2 years agoDelbert
2 years agoJustine
2 years agoYun
2 years agoParis
2 years ago