PAES 311: 2001 Flashcards
a mechanical device designed specifically to hold, join, or maintain
Fastener
an externally threaded fastener designed for insertion through holes in assembled parts, and normally tightened or released by torquing a nut.
Bolt
a block or sleeve having an internal thread designed to assemble with the external thread on a bolt, screw, stud or other threaded part.
Nut
the designation used for the purpose of general identification; for external and internal threaded fasteners usually is the basic major diameter of the thread.
Nominal Size
the distance from the intersection of the largest diameter of the head with the bearing surface to the extreme end of the fastener, measured parallel to the axis of the fastener.
Length of fastener
a thread which winds in a clockwise and receding direction from the starting end, when viewed from that end.
Right hand thread
a thread which winds in a counterclockwise and receding direction from the starting end, when viewed from that end.
Left hand thread
The specified load which the fastener must withstand without any indication of permanent deformation after the load is released.
Proof load
The distance between corresponding points on adjacent thread forms.
Pitch
the diameter bounding the crest of an external thread or the root of an internal thread.
Major diameter
the diameter bounding the root of an external thread or the crest of an internal thread
Minor diamter
the diameter of the imaginary cylinder whose surface passes through the thread profiles making the widths of the thread ridge and the thread groove equal
Pitch diameter
Hexagon head (Bolts)
General purpose
Used when side of the head is not accessible for wrench and screwdriver
Round head square neck (Bolts)
Hexagonal (nuts)
General purpose
Used when pin is needed for locking the
fastener assembly
Hexagonal slotted (nuts)
Used to increase the bearing are and distribute the fastener load
Hexagonal flange (nuts)
Black oxide, blue used on
Steel
Rust preventives are used on
All metals
Electrogalvanized zinc are used on
All metals
Hot dip zinc are used on
All metals
Chromium plate are used on
Most metals
Dull nickel are used on
Most metals
Bright nickel are used on
Most metals
Black chromate
Zinc plated or cadmium plated steel
Passivating are used on
Stainless steel
Used for general use, especially in non-taped steel materials
Coarse thread series
Used in applications with vibration but not recommended for brittle materials
Fine thread series
