1 / 33

ERT 249 CAD FOR BIOSYSTEMS ENGINEERING

ERT 249 CAD FOR BIOSYSTEMS ENGINEERING. SECTIONING. PREPARED BY: SAMERA BINTI SAMSUDDIN SAH SCHOOL OF BIOPROCESS ENGINEERING. Outline. Purpose. Sectioned Drawings . The Cutting Plane. The Cutting Plane.

magnar
Download Presentation

ERT 249 CAD FOR BIOSYSTEMS ENGINEERING

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ERT 249 CAD FOR BIOSYSTEMS ENGINEERING SECTIONING PREPARED BY: SAMERA BINTI SAMSUDDIN SAH SCHOOL OF BIOPROCESS ENGINEERING

  2. Outline

  3. Purpose

  4. Sectioned Drawings

  5. The Cutting Plane

  6. The Cutting Plane • Cutting planes may be labeled at their endpoints if multiple cutting plane lines are used • When using multiple cutting planes each sectioned drawing is drawn as if the other cutting plane lines do not exist • The cutting plane line takes precedence over center lines • Occasionally cutting plane lines are not shown when their location is obvious

  7. Section Lines • Section lines are drawn where the object passes through the cutting plane • If a saw was used to cut the part then section lines represent the cutting marks left by the saw blade • Different materials may be represented by the use of different section line types • The general section line type which may be used for any material is the line type for iron

  8. Section Lines • Section lines should not be parallel or perpendicular to object lines • Section lines are generally drawn at 45 degrees unless this conflicts with other rules • Section lines should be oriented at different angles for separate parts • Occasionally section lines are only drawn on the perimeter of large areas • Section lines are not used for thin parts rather they are filled in solid (Do not use closely spaced section lines)

  9. Section Drawing Types • Full Section • Half Section • Assembly Section • Offset Section • Broken-Out Section • Revolved Section • Removed Section • Special Section Conventions

  10. Full Section • The cutting plane passes completely through the part as a single flat plane

  11. 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

  12. Assembly Section • Shows how parts fit together • Different parts have different section line orientation • Different materials use different section line types • Standard parts (shafts, pins, dowels, rivets, screws, washers, gears, etc.) are not sectioned

  13. Assembly Section • Cut each part of the assembly and section each part with the appropriate section line type • Put the parts together in their assembled position

  14. Assembly Section • The shaft is not sectioned because it is a standard part and section lines would provide no additional information • The other two part are made from the same material • The orientation of section lines clearly shows the location of the different parts

  15. Assembly Section • The top and bottom mating part are made from different materials in the part shown below • A center line is added to the shaft to show that it is a circular feature

  16. Offset Section • The internal features of many part can not be shown using a single straight cut to create the sectioned drawing • An offset section is used for such parts

  17. 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

  18. Offset Section • An offset section allows the cutting plane to pass through all of the internal features • There may be several bends in the cutting plane

  19. Offset Section • The actual part would show a new visible line 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

  20. Offset Section • The sectioned view does not show the bend in the cutting plane • Hidden lines are not shown • Be sure to include object lines that are behind the cutting plane

  21. 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

  22. Revolved Section • A cross section of the part is revolved 90 degrees and superimposed on the drawing • A jagged break line may be used to divide the revolved section from the rest of the drawing

  23. Removed Section • Similar to the revolved section except that the sectioned drawing is not superimposed on the drawing but placed next to it • The view and the cutting plane are labeled (Section A-A) • The removed section may be drawn at a different scale

  24. Special Section Conventions • 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

  25. Special Section Conventions • The object is difficult to understand using standard multiviewdrawings where hidden lines are used to represent internal features

  26. Special Section Conventions • If the part is sectioned as it would actually appear if cut the details of the ribs and holes would not be clear • Since the objective is to make the drawing easy to interpret the drawing is modified following standard conventions

  27. Special Section 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 appear as a full section • The arrows show the direction of the view

  28. Special Section Conventions • Ribs are not sectioned when the cutting plane passes through them lengthwise • Ribs are sectioned if the cutting plane passes through them at other orientations

  29. Special Section Conventions • The front view is replaced by a full section view • The cutting plane shown in the top 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

  30. Sectioning With Solid Models • Slice • cuts the solid object at the specified cutting plane using the current color • breaks the objects into two parts • one part may be deleted or moved • Section • creates a 2-D drawing of the section • only draws the portion of the object that is cut (i.e. the portion of the object that has section lines)

  31. Sectioning With Solid Models • SLICE command • SECTION command

  32. Sectioning With AutoCAD • Use BHATCH • Use the correct scale • Default line orientation is 45 degrees • The general line type is ANSI31 • Use different line types for different materials • Use PICK POINTS to select an internal point in the sectioned portion of the drawing

  33. THE END...

More Related