Ch. 11: Threads Flashcards
A ____ is a V-shaped ridges that follow a helical (spiral) path along a cylindrical shape
thread
External threads are on ____ surfaces
external
external threads can be found on ___ and ____
bolts, screws
_____ is the top of a thread
Crest
_____ is the bottom of a thread
root
________ is the largest diameter of a thread
major diameter
______ is the smallest diameter of a thread
minor diameter
________ is the diameter of imaginary cylinder passing through thread where the thread ridge width is equal to the groove width
pitch diameter
_____ is the distance from a point on one thread to the corresponding point on the next thread
Pitch
thread depth is the _____
difference between crest and root
_____ is the axial distance a thread will travel in one complete turn
Lead
_____ is a grouping that defines type of thread based on number of threads per inch for external and internal threads
thread series
____ threads (UNC) for general applications and automatic assembly
coarse
Class 1 indicates a ____
loose fit for easy assembly and disassembly
the letter ___ represents external threads
A
Internal threads can be cut by hand using a ___
tap
do not mesh _____ and _____
ISO metric, United threads
______ defines the fit or tolerance between an external thread and the mated internal thread
thread class
Class 2 indicates _____
a closer tolerance and is used for general production of fasteners such as bolts , screws, and nuts
Class 3 indicates ____
a tighter tolerance than provided in the other classes
Unless designated, all screw threads are _____
single-start threads
In a ____, Class 1, 2, or 3 fit designation and the letter A for external threads or B for internal threads
Thread class
_____ is a specification for the depth of internal threads or length of external threads is optional
Thread depth
______ is the profile shape that defines a thread
thread form
