Fastener Testing & Quality Control Flashcards
7 cards from real CFS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Fastener Testing & Quality Control flashcards as text
In a salt spray (fog) test per ASTM B117, what does the 'hours to first red rust' measure?
Answer: Corrosion resistance of the coating or base metal
Salt spray testing evaluates how long a coating or base material resists corrosion under an accelerated saline environment.
What is the primary purpose of a proof load test on a bolt?
Answer: To verify the bolt can sustain a specified axial load without permanent set
A proof load test applies a defined tensile load and confirms the fastener returns to its original length after removal, verifying no permanent deformation occurred.
Which test method evaluates the risk of stress corrosion cracking in high-strength fasteners?
Answer: Slow strain rate test or sustained load test in corrosive media
Stress corrosion cracking susceptibility is assessed by exposing stressed fasteners to a corrosive environment over time to detect delayed fracture.
A batch of Grade 8 bolts shows surface hardness above the maximum specified. What is the primary concern?
Answer: Increased susceptibility to hydrogen embrittlement and brittle fracture
Excessively hard fasteners (over-tempered or improperly processed) are more susceptible to hydrogen embrittlement and sudden brittle failure.
What does 'dimensional inspection' of a fastener typically verify?
Answer: Physical measurements against drawing or standard tolerances
Dimensional inspection uses calibrated gauges and instruments to confirm length, diameter, head height, thread pitch, and other physical dimensions are within specification.
Which organization publishes the Industrial Fastener Institute (IFI) standards used in quality control?
Answer: Industrial Fastener Institute
The Industrial Fastener Institute publishes IFI standards specifically addressing fastener quality, testing, and application practices.
What is the correct action when a fastener lot fails a proof load test?
Answer: Quarantine the lot and initiate a non-conformance report
A lot that fails proof load testing must be quarantined and processed through a formal non-conformance disposition—accept, reject, rework, or use-as-is with engineering approval.