std drawing Flashcards
What are the two types of screw threads?
Left-hand and right-hand threads
Right-hand threads are the most commonly used, while left-hand threads are for special applications.
What is the gender of threads?
Male and female
A bolt has male threads, while its matching hole has female threads.
Define lead in the context of screw threads.
The distance along the screw’s axis covered by one complete rotation of the screw
Lead is measured in millimeters.
Define pitch in the context of screw threads.
The distance from the crest of one thread to the next
Pitch is also expressed in millimeters.
How are threaded fasteners illustrated in engineering drawings?
With detailed, schematic, or simplified representations
This varies depending on the complexity required.
What does the designation ‘M’ indicate in metric ISO screw threads?
‘M’ indicates a metric ISO screw thread
It is followed by nominal diameter and pitch values.
What is the format for designating a metric ISO screw thread?
M followed by nominal diameter D and pitch P, separated by ‘x’ (e.g., M8×1)
The pitch can be omitted if it is the coarse pitch.
What is a counterbore (CBORE) hole?
A type of hole represented in engineering drawings
It allows for a flat bottom and larger diameter at the top.
What is a countersink (CSK) hole?
A hole that is tapered to allow for flush mounting of fasteners
It is commonly used with screws.
Fill in the blank: A bolt has ______ threads.
male
This refers to the external threads of the bolt.
Fill in the blank: The distance from the crest of one thread to the next is called ______.
pitch
This is a crucial measurement in screw design.
True or False: The coarse pitch is the commonly used default pitch for a given diameter.
True
Coarse pitch is typically used unless a fine pitch is specified.
