API 653 – 571 SECTION 6 EXAM QUESTIONS AND ANSWERS 2024

What does "L" mean in Austenitic SS, like 304L? - ANSWERS Has a low carbon content What does "H" mean in Austenitic SS, like 316 H? - ANSWERS Has a high carbon content Low alloy steels can contain up to: - ANSWERS 9% chrome Nickel alloys are materials that have over: - ANSWERS 30% nickel A Brittle Fracture: - ANSWERS grows very rapidly with minimum deformation prior to failure Resistance to Brittle Fracture is called: - ANSWERS toughness What test is used to determine a material's toughness? - ANSWERS Charpy impact test Most brittle failures occur: - ANSWERS below the impact transition temperature A 4" thick 5 Chrome vessel operates at 1200 psig and 900 degrees Fahrenheit. When is this vessel least likely to fail by Brittle Fracture? - ANSWERS Normal Operation Most brittle failure's apear as: - ANSWERS cleveage Mechanical Fatigue is caused by: - ANSWERS cyclic stresses occurring over a long period of time Fatigue will not occur in carbon steel if stresses are below the: - ANSWERS endurance limit The endurance limit is usually about: - ANSWERS 40-50% of a material's ultimate tensile strength. Which material does not have an endurance limit? - ANSWERS Stainless steel Mechanical Fatigue can cause cracks that initiate from the surface and often form a: - ANSWERS clam shell appearance The best defense against Mechanical Fatigue is a: - ANSWERS good design that minimizes stress concentrations Inspecting for high-cycle Fatigue can be difficult since: - ANSWERS once the crack begins, only a few cycles are needed for the crack to lead to failure Atmospheric Corrosion is of greatest concern in: - ANSWERS wet climates in industrial locations List the approximate corrosion rate from Atmospheric Corrosion based on the following conditions.