2TOPICSSection view representationof rib, web, spoke and lug.Aligned sectionConventional break
3Section view representation of rib, web, spoke and lug
4CONVENTIONAL PRACTICE There are some exceptions to the general rules of sectioning:Webs, ribs, lugs, spokes,Shafts, rods, spindles,Bolts, nuts and thin washers.Rivets, dowels, pins and cotters.
5The cross-section is technically correct. CONVENTIONAL PRACTICEThe cross-section is technically correct.The convention in a drawing is to show the preferred method for sectioning this type of object.NOT RECOMMENDEDCORRECTConvention Rotation
6TERMINOLOGYRib and Web are thin, flat feature of an object that acts as a structural support.RibRib
7TERMINOLOGYA web or rib is a strengthining or supporting part of a component.Web
8TERMINOLOGYSpoke is the rod radiating from the hub to the rim of a wheel.HubHubSpokeRimSpokeRim
9TERMINOLOGYLug is an ear which is built as portion of an object for attachment.
10TERMINOLOGYLug is an ear which is built as portion of an object for attachment.
11CONVENTIONAL PRACTICE Omit the section lines on the section view ofRib, Web and Lug, if the cutting plane is passed flatwise through.Spoke, if the cutting planeis passed longwise through.
12CONVENTIONAL PRACTICE When the cutting plane passes through a rib longtudinally it is not sectioned
13CONVENTIONAL PRACTICE When the cutting plane passes through the rib transversely it should be sectioned
14EXAMPLE : RIB Normal multiview drawing Normal section view Section view drawing with convention
15EXAMPLE : WEB : flatwise cut Normal multiview drawingNormal section viewSection view drawing with convention
21DEFINITIONAligned section is used when features are located on radial linesAligned section is a section view that is drawnby imaginary rotating the object’s featuresappeared in a principal view about symmetryaxis
22Gives the impression that this holes are at unsymmetrical position. Example : HoleGives the impression that this holes are at unsymmetrical position.
29CONVENTIONAL PRACTICE For long objects that have to draw in a small scale to fit them on the paper, it is recommended to remove its long portion (which contains no important information) and draw the break lines at the broken ends.