Graphics in Industry and Standards Flashcards
The Design Cycle:
identified needs > market research > specification > idea refinement > product design > production design > presentation of goods > orders/marketing
the 3P’s:
- Prelimenary graphics: rough drawings planning the product, show customers ideas
- Production graphics: drawings with dimensions and scales showing the manufacturer how to make the product
- Promotional graphics: flyers or leaflets showing detailed renders of the product to sell and attract customers
Title Blocks include:
> name > projection symbol > drawing number > title > date > original scale > tolerances
Scales:
reduction scales: 1:2, 1:5, 1:10, 1:20, 1:50, 1:100, 1:200, 1:500, 1:1000
enlargement scales: 2:1, 3:1, 10:1, 20:1, 50:1
Lines - Continuous thick
visible outlines and edges
Lines - Continuous thin
dimensioning, haching, projection and leader lines etc.
Lines - Continuous thin irregular
limits of partial or interrupted view and sections if the limit is not an axis
Lines - Continuous thin with straight zig zags
limits of partial or interrupted view and sections if the limit is not an axis
Lines - Dashed thin
hidden outlines and edges
Lines - Chain thin
centre lines, lines of symmetry, trajectories and pitch lines and pitch circles
Lines - Chain thin thick at ends / changes direction
cutting planes
Lines - double dashed chain thin
outlines and edges of adjacent parts, outlines and edges of alternative and extreme positions of movable parts, initial outlines prior to forming, bend lines on developed blanks or patterns
Auxiliary views
view added to main view of product to impart more information about product. completely new elevations of product used to give true representations of features that cannot be achieved by orthographic
Sectional Views - Local/Part sectional view
sectional view of specific part (ie screw) of a product
Sectional Views - Half sectional view
sectional view from the axis of symmetry
Sectional Views - Revolved Sectioal
showing the inside of a circular item
Sectional Views - Removed Sections
removing a view from original part to see more clearly the section
Partial / Interrupted Views
Partial Views:
showing a small part in more detail to improve clarity
interrupted views:
showing only the portions of a long or large object that are necessary to define it
drawn close to each other and break lines are used to define it
Drawing symbols
Flat surface - X on surface
knurling - straight lines in centre of surface
diamond knurling - straight lines at 30 degrees to centre line
hatching - diagonal lines across surface to show cut surface
Symbols and Abbreviations - (/) circle with line, M, NTS, R
> diameter
metric thread
not to scale
radius
Dimensioning - General Principles
> no more than necessary
linear dimensions stated in mm
if other units used symbols must be shown
crossing of projection/leader lines avoided
dimensions should not be crossed by other lines in drawing
Dimensioning - Parallel
> originate from a common reference feature
dimensions on top of each other, all starting at same place but ending at different points
Dimensioning - Combined
> combination of parallel and chain
> used when space is limited or drawing is complex
Dimensioning - Chain
> chain of dimensions
leads to accumulation of tolerances that affect function of part
(next dimension begins where last one ends)
Dimensioning - Running
> Common origin
dimension shown at each stage
Dimensioning - Chamfers
chamfers at 45 degrees shown: (width) x 45degrees
any other angle should be shown as a separate dimension
Tolerances
not economic to throw away every part that does not fit
tolerances overcomes this problem
unless otherwise stated, tolerances are +-0,25 and +-0,30degrees`
Tolerance methods
Common:
shows upper limit placed above lower limit
Symmetrical:
shows the normal size and the symmetrical tolerance band (e.g. 42+-0,15)
Asymmetrical:
shows nominal size plus upper and lower limits of tolerance band
