Lines
These are thick contious lines that represent all edges visible
Visible lines
Thin lines used to indicate where on a drawing a demension note appears
Leaders
General term for size, may not be accurate
Nominal size
The measured size
Actual size
Defines connection of equipment or installation, shows physical arrangement of components
Wiring diagram
These are short dashes that represent all edges that are not visible
Hidden lines
Include short wavy, long and thin, and S type
Break lines
Size of a part determined my engineering and design requirements
Basic size
Total amount of variation permitted from the design size of a part
Tolerance
Form of wiring diagram that shows external connections between unit assembly
Interconnection diagram
Designate center of holes
Center line
Thick broken line used to indicate where an imaginary cut takes place to show the interior
Cutting plane line
Intentional difference in dimension of mating parts
Allowance
Points, axis or planes of a part that are assumed to be exact
Datum
Depicts inter-relationship of various components of a system, through graphic symbols the electrical connections and functions of a specific circuit arrangement
Schematic diagram
These are thin lines that indicate extent and direction of dimensions
Extension lines
Thin horizontal lines drawn at 45 degrees; indicates solid portions of a sectional viee
Section plane lines
Size of a part after allowance and clearance and tolerances have been applied
Design size
General term used to signify the range of tightness
Fit (clearance, interference, transition)
Uses one type or more of different drawings
Combine drawing
Thin lines terminated by arrowheads against extension lines
Dimension lines
Thin lines composed of long dashes, used to indicate alternate positions of moving parts, adjacent positions of related parts and, indicated datum
Phantom lines
Extreme permissable dimensions of a part, a min and max
Limits
Algaebraic difference between a size and the corresponding basic size
Deviation
A circular shape containing a number used to identify items located in a drawing
Balloon system