Greenfaulds High School Higher: Graphic Communication Sectioned Assembly
Vertical Section
Horizontal Section
Cutting Plane
Sections (Webs)
Half Section
Part Section
Revolved Section
Exceptions Sectioning is a process which should be used only to simplify or clarify a drawing. There are some engineering details that, if sectioned, lose their identity or would create a wrong impression. These items are never sectioned.
Exceptions
Engineering details that do not show hatching when sectioned Nuts & Bolts Studs Screws Shafts Webs Ball Bearings & Ball Races Roller Bearings & Roller Races Keys Pins Gear Teeth
Hatching Hatching is used in British Standards therefore it is also used throughout the Higher course. Hatching is drawn using type B lines. Equally spaced at 45 degrees Preferably not less than 4 mm apart However if hatching a small area spacing should be reduced but never less than 1mm
Hatching Single Component When hatching separated areas of a single component the hatching lines should be in the same direction & with the same spacing.
Hatching Adjacent Parts Where different sectioned parts meet on an assembly drawing, the direction of hatching should normally be reversed & staggered.
Hatching Adjacent Parts In cases where hatching on adjacent parts must be at the same angle the lines should be staggered & may be more closely spaced.
Hatching Large Areas Hatching of large areas may be limited to that part of the area which touches adjacent parts, or the outline of the large part.
Hatching Thin Material Thin Material in section may be filled in, in preference to showing the material thickness out of scale & hatched. When adjacent parts are thus shown a clear space of not less than 1mm should be left between them.
Questions For B3 (TG2) a.The elevation of the full assembly, showing all hidden detail. b.The SECTION A-A, omitting hidden detail. Dimensioned orthographic views together with an exploded isometric view of a webbed pulley as shown. On Worksheet B3 draw full size, using the given dimensions.