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Engineering Drawing
Lecture 14Section Views
University of PalestineCollege of Engineering & Urban PlanningFirst Level
Lecturer:Eng. Eman Al.SwaityEng.Heba hamad
TOPICS
Introduction
Terminology & common practices
Kind of sections
Dimensioning
Introduction
Object
GRAPHICS COMMUNICATION WITH ENGINEERING DRAWING
Workingdrawing
Clear ?
Orthographicprojection
(convention)
Section viewsconvention
Section Views
Orthographic Projection
Finish
Yes
No
Dimensioning
PURPOSES OFSECTION VIEWS
Clarify the views by
Facilitate the dimensioning.
v reducing or eliminating the hidden lines.
v revealing the cross sectionals shape.
Let See the example
EXAMPLE : Advantage of using a section view.
Terminology andcommon practices
Cuttingplane
CUTTING PLANE
Cutting plane line
Cutting plane is a plane that imaginarily cutsthe object to reveal the internal features.
Section lines
Cutting plane line is an edge view of the cutting plane.
CUTTING PLANE LINE
Indicate the pathof cutting plane.
ANSIstandard
Thick line
Thick line
JIS & ISOstandard
Thin line
CUTTING PLANE LINESTYLES
Viewingdirection
Viewingdirection
Viewingdirection
This course
SECTION LININGSection lines or cross-hatch lines are used toindicate the surfaces that are cut by the cuttingplane.
Sectionlines
Drawn with
2H pencil.
SECTION LINES SYMBOLS
The section lines are different for each of materials type.
Cast iron,Malleable iron
Steel Concrete Sand Wood
For practical purpose, the cast iron symbol is used most often for any materials.
SECTION LINING PRACTICE
The spaces between lines may vary from 1.5 mm
for small sections to 3 mm for large sections.
COMMON MISTAKE
SECTION LINING PRACTICEIt should not be drawn parallel or perpendicularto contour of the view.
COMMON MISTAKE
Kinds of Sections
KIND OF SECTIONS
1. Full section
2. Offset section
3. Half section
4. Broken-out section
5. Revolved section (aligned section)
6. Removed section (detailed section)
FULL SECTION VIEW
FULL SECTION VIEWThe view is made by passing the straight cutting plane completely through the part.
OFFSET SECTION VIEWThe view is made by passing the bended cutting plane completely through the part.
Do not show the edge viewsof the cutting plane.
TREATMENT OF HIDDEN LINESHidden lines are normally omitted from sectionviews.
HALF SECTION VIEWThe view is made by passing the cutting plane halfwaythrough an object and remove a quarter of it.
HALF SECTION VIEWA center line is used to separate the sectioned half from the unsectioned half of the view.Hidden line is omitted in unsection half of the view.
The view is made by passing the cutting plane normal to the viewing direction and removing the portion of an object in front of it.
BROKEN-OUT SECTION VIEW
A break line is used to separate the sectioned portion from the unsectioned portion of the view.
BROKEN-OUT SECTION VIEW
There is no cutting plane line.
Break line is a thin continuous line (
4H) and is drawn freehand.
EXAMPLE : Comparison among several section techniques
Dimensioningin Section View
In most cases, dimensioning of the section viewsfollows the typical rules of dimensioning.
GOODPOOR
GOODPOOR
f
50
10
f
50
10
DIMENSIONING
For a half-section view,use dimension line withonly one arrowhead thatpoints to the position insidethe sectioned portion.
f
50
DIMENSIONING
Slide1TOPICSIntroductionSlide75PURPOSES OFSECTION VIEWS Slide76Terminology andcommon practicesSlide98Slide7Slide79SECTION LININGSlide82Slide22Slide83Kinds of SectionsKIND OF SECTIONSFULL SECTION VIEWFULL SECTION VIEWOFFSET SECTION VIEWSlide27HALF SECTION VIEWSlide26Slide43Slide84Slide87Dimensioningin Section ViewSlide16Slide45Slide42