ENGR-22_Lec-12_Section-Views-2.ppt 1 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Bruce Mayer, PE Registered Electrical & Mechanical Engineer Engineering 22 Section Views-2

ENGR-22_Lec-12_Section-Views-2.ppt 2 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Learning Goals  Properly Create Section (Cut- Away) Views to Show Internal Features Of Objects That Are Not Easily Understood In Standard Orthographic Projection View Drawings

ENGR-22_Lec-12_Section-Views-2.ppt 3 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Learning Goals cont  Use and/or Apply How & Where to Construct the Cutting Plane Line Section Lines (a.k.a. “Hatch Lines”) Several Types of Section Drawings

ENGR-22_Lec-12_Section-Views-2.ppt 4 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Section Drawing Types  Full Section (done so far)  Half Section  Offset Section  Broken-Out Section  Revolved Section  Removed Section  Special Section Conventions

ENGR-22_Lec-12_Section-Views-2.ppt 5 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Full Section  The cutting plane passes completely through the part as a single flat plane

ENGR-22_Lec-12_Section-Views-2.ppt 6 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Half Section  The cutting plane only passes half way through the part  The other half is drawn as usual  Hidden lines are not shown on either half of the part  A center line is used to separate the two halves  Mostly used on cylindrical parts

ENGR-22_Lec-12_Section-Views-2.ppt 7 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Offset Section  The multiview drawing is often difficult to interpret when there are several hidden features on the object  A sectioned view makes the object much easier to understand  An offset section allows the cutting plane to pass through all of the significant internal features  There may be several bends/kinks in the cutting plane

ENGR-22_Lec-12_Section-Views-2.ppt 8 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Offset Section cont  The actual part would show a new visible line (at the edge) at the bend in the cutting plane Since the cutting plane bend is arbitrary, do not show the line representing this bend in the sectioned drawing  Hidden lines are NOT shown  Be sure to include object lines BEHIND the cutting plane

ENGR-22_Lec-12_Section-Views-2.ppt 9 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Broken Out Section  Only a portion of the view is sectioned  A jagged break line is used to divide the sectioned and unsectioned portion of the drawing

ENGR-22_Lec-12_Section-Views-2.ppt 10 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Revolved Section  A cross section of the part is revolved 90° and superimposed on the drawing  A jagged break line may be used to divide the revolved section from the rest of the drawing

ENGR-22_Lec-12_Section-Views-2.ppt 11 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Revolved Section Caveats  Superimposition of Rev-Sec requires Removal of All ORIGINAL Lines Underneath the Section  Retain the TRUE- SHAPE of the Rev-Sec Regardless of the Line- Direction in the Visible- View

ENGR-22_Lec-12_Section-Views-2.ppt 12 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Removed Section  Similar to the revolved section except that the sectioned drawing is not superimposed on the drawing but placed adjacent to it  The view and the cutting plane are labeled (Sec. A-A)  The removed section may be drawn at a different scale Very Useful for Detailing Small Parts or Features

ENGR-22_Lec-12_Section-Views-2.ppt 13 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Intersections - Windows a)The Offset of the intersection from the Visible Lines is SMALL or Negligible Can DisRegard the True Projection and Align to Vis-Lines b)The Larger Intersection Does Have a Substantial Offset From the Visible Lines Use the True-Projection to position the intersection

ENGR-22_Lec-12_Section-Views-2.ppt 14 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Intersections - PortHoles c)The Offset of the intersection from the Visible Lines is SMALL or Negligible Can DisRegard the True Projection and Align to Vis-Lines d)Larger Intersections For the Smaller Hole Use Tube OD (R 1 ) and ID (r 1 ) Arc at Depth Found by True Projection For Hole K, r k = r 1, SemiEllipses of Intersection appear as Straight-Lines

ENGR-22_Lec-12_Section-Views-2.ppt 15 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Special Sections  There are special rules (conventions) that are followed to make some parts more understandable  Some features are rotated to their TRUE RADIAL position in sectioned views  The object is difficult to understand using standard multiview drawings where hidden lines are used to represent internal features

ENGR-22_Lec-12_Section-Views-2.ppt 16 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Special Sections cont  Many Times If a part is sectioned as it would actually appear if cut, the details of Features such as ribs and holes may not be clear  Since the goal is to make the drawing easy to interpret the drawing is modified by the following std conventions The cutting plane shows that the features are revolved to their true radial position Hidden features are not shown The sectioned drawing produced is a DISTORTED, but CLEARER, picture of the object The section drawing appears as a full section The arrows show the direction of the view

ENGR-22_Lec-12_Section-Views-2.ppt 17 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Special Sections cont  Ribs/Webs are not sectioned when the cutting plane passes through them lengthwise  Ribs are sectioned if the cutting plane passes through them at other orientations

ENGR-22_Lec-12_Section-Views-2.ppt 18 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Special Sections cont  The side view is replaced by a full section view  The cutting plane shown in the Front view shows the direction of the line of sight  The holes and ribs have been revolved to their true radial position  The ribs are not sectioned in this orientation  The section lines are all drawn at the same angle since the object is one solid part

ENGR-22_Lec-12_Section-Views-2.ppt 19 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Conventional Breaks  Use Conventional Breaks to Shorten an Elongated Object  “Jagged” Lines are used to Break Non-Circular Cross-section Objects  “S” Breaks are Preferred for Cylindrical Objects

ENGR-22_Lec-12_Section-Views-2.ppt 20 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Demo – Pipe Intersection  Let’s make a Cross Section for a Drilled, Thick- Walled Pipe

ENGR-22_Lec-12_Section-Views-2.ppt 21 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Final Result

ENGR-22_Lec-12_Section-Views-2.ppt 22 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics All Done for Today Blue Print CrossSec Circa 1862

ENGR-22_Lec-12_Section-Views-2.ppt 23 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Bruce Mayer, PE Licensed Electrical & Mechanical Engineer Engr/Math/Physics 25 Appendix 

ENGR-22_Lec-12_Section-Views-2.ppt 24 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Intersect Demo

ENGR-22_Lec-12_Section-Views-2.ppt 25 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Intersect Demo cont

ENGR-22_Lec-12_Section-Views-2.ppt 26 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Hatch Procedure-1

ENGR-22_Lec-12_Section-Views-2.ppt 27 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Hatch Procedure-2  Hatch DiaLog Box 4

ENGR-22_Lec-12_Section-Views-2.ppt 28 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Hatch Procedure-3  Pick Hatch Areas by Clicking ONCE ANYwhere within the Region

ENGR-22_Lec-12_Section-Views-2.ppt 29 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Hatch Procedure-4

ENGR-22_Lec-12_Section-Views-2.ppt 30 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Hatch Procedure-5  All Done