API 653 – 571 SECTION 6 EXAM QUESTIONS AND ANSWERS 2024

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. a. Dry rural environments____ b. Inland locations with moderate humidity or rainfall __ c. Industrial environments with airborne acids/sulfur compounds _____ d. Marine environments__ - ANSWERS 1, 1-3, 5-10, 20 A key place for Atmospheric Corrosion is: - ANSWERS where piping rests on a pipe support Atmospheric Corrosion: - ANSWERS can cause either uniform or localized wall loss The best way to prevent failures by Atmospheric Corrosion is to: - ANSWERS install and maintain appropriate coatings CUI is an inspection concern for insulated carbon steel equipment that operates between: - ANSWERS 10 to 350 deg.F CUI is an inspection concern for insulated austenitic stainless steel equipment that operates between: - ANSWERS 140-400 deg.F CUI is an inspection concern for insulated vessel that operates at 500 deg.F and: - ANSWERS is in intermittent service CUI is most severe when metal temperatures are between: - ANSWERS 212 to 350 deg.F If the metal temperature increases, while still in the CUI temperature range, the corrosion rate: - ANSWERS will increase CUI on carbon steel or low alloy materials appear as: - ANSWERS localized pitted or localized wall loss CUI on 300 Series stainless steel materials appear as: - ANSWERS cracking or localized pitting or localized wall loss What causes the CUI cracking on 300 series stainless steel materials? - ANSWERS Chlorides Microbiologically Induced Corrosion is caused by: - ANSWERS living organisms MIC occurring in carbon steel usually forms: - ANSWERS cup-shaped pits MIC occurring in 300-series stainless steel usually forms: - ANSWERS sub-surface cavities To prevent MIC equipment and piping having water should be treated with: - ANSWERS biocide