Fastener Selection & Application Flashcards

Which fastener type is best suited for joining two thin sheet metal panels where access is only available from one side?

Answer: Blind rivet (pop rivet)

Blind rivets are designed for one-sided access applications where the back of the joint is inaccessible.

A fastener is needed to connect wood to masonry in an outdoor environment. Which option is most appropriate?

Answer: Hot-dip galvanized lag screw

Hot-dip galvanized fasteners provide superior corrosion protection for outdoor wood-to-masonry connections.

When selecting a fastener for a joint subject to significant vibration, which feature is most important?

Answer: Locking capability

Vibration loosening is the primary concern, so locking features such as nylon inserts, serrated flanges, or lock washers are critical.

Which thread form is standard for general-purpose fasteners in the United States?

Answer: Unified National (UN)

The Unified National thread system is the US standard for general-purpose fasteners, encompassing UNC, UNF, and UNEF series.

A bolt is specified as 1/2-13 UNC Grade 5. What does '13' represent?

Answer: Threads per inch

In the designation 1/2-13, '13' is the number of threads per inch (TPI) for that diameter.

For a flanged joint on a pressure vessel, which bolt pattern consideration is most critical for uniform sealing?

Answer: Applying bolts in a star or cross pattern during tightening

A star or cross-tightening pattern distributes clamping force evenly across the gasket, preventing leaks.

Which fastener material is preferred when electrical conductivity must be minimized in the joint?

Answer: Nylon (polymer)

Nylon and other polymer fasteners are non-conductive and are used in electrical and electronic applications to prevent current paths.