Basic HTML Version
3
5
Brainstorming
Describe what you can see in
this picture and the way in which it has been
drawn.
6
Read the passage and underline the words that define these two different types of drawing.
To sum up
1
, a drawing consists of three main parts:
1
dimensions, symbols, explanatory and instruction notes;
2
a title block, that is a system of labelling, containing the information
required for identification and interpretation of the drawing;
3
one or more views of an engineering component.
The limits of size of components are usually stated in the title block.
There are two ‘limits’: the maximum and the minimum permissible
size to which any component feature can be made.
Tolerance
is the
difference between the limits of size. The nominal size, however, is the
nearest whole millimetre or fractional inch size of the feature.
1
to sum up
: to state the main point of something in a short and clear form, to
summarize
border
bordo
convention
convenzione
(to) draw to scale
disegnare in scala
drawing board
tavola da disegno
eraser
gomma
ink
inchiostro
ruler
righello
size
dimensione
T-square
squadra a T
tolerance
tolleranza (differenza di misura tra limiti minimi e massimi permessi)
TECHNICAL ENGLISH
Isometric and orthographic drawings
I
sometric drawing
is a method used to create a
3-D view of a design idea or a product. It is the
method of drawing that offers a truer image of the
final product than any other type does.
It follows certain conventions:
- the closest
1
part of the object to the person looking
at it is a
corner
;
- all horizontal lines of the product are at 30° to the
horizontal;
- vertical features remain vertical;
- all measurements are to scale.
However,
orthographic drawing
or
projection
is the most widely adopted method used to
produce technical drawings. In order to make a
part, an engineer
needs to know the
dimensions of all
its
features
and
an
orthographic
projection
offers
three, 2-D views of
a part.
Most orthographic
drawings are “third angle projections”, which shows
the part from the
top
(plan elevation), the
side
(end
elevation) and the front (front elevation).
The three elevations are laid out in an L-shape. The
front view is underneath the plan view, the end view
is to the right of the front view.
1
closest
: nearest
TEXT 3
Drawing-board.
Orthographic Projection.
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