WS9-3 PAT301, Workshop 9, October 2003 n Problem Description u In this exercise you will first create a new database and then import CAD geometry using an IGES file. It consists of several trimmed and simple surfaces. Note the surfaces that are imported make-up one-quarter of the model. Once the geometry is imported, you will create several new surfaces to complete the model full model. Then you will create a solid from the surfaces. It will be a B-rep solid (Boundary representation).
WS9-4 PAT301, Workshop 9, October 2003 n Suggested Exercise Steps 1. Create a new database and name it Anchor.db. 2. Set New Model Preferences Tolerance to Based on Model with an Approximate Maximum Model Dimension of 70. Set the Analysis Code to MSC.NASTRAN and Analysis Type to structural. 3. Import the IGES file Anchor.igs. 4. Using the Viewing icons change the orientation of the model to better visualize it in. 5. Create a missing surface by using Create/Surface/Curve/2 Curve. 6. Create second missing surface by using Create/Surface/Trimmed/Planar and Auto Chain to connect free surface edges. 7. Delete the two surfaces that would be interior to the solid. The solid will be created by mirroring the surfaces twice.
WS9-5 PAT301, Workshop 9, October 2003 n Suggested Exercise Steps 8. Make surface for constraining using bolt and washer. Create center points by ArcCenter method. Create cylindrical coordinate system using the points that were just created. Transform free surface edge by translating using cylindrical coordinate system. Break the surface into two surfaces. 9. Create surface for pressure load. Break surface by parametric option. Add vertices. 10. Mirror surfaces. 11. Mirror surfaces again. 12. Create solid by using B-rep method. 13. Show just final solid. 14. Close and Exit MSC.Patran.
WS9-6 PAT301, Workshop 9, October 2003 Step 1: Create New Database Create new database. a.File / New… b.Specify database name in File name, Anchor.db c.Click OK. a c a b
WS9-7 PAT301, Workshop 9, October 2003 Step 2: Set Model Preferences New Model Preferences form Select Based on Model for Tolerance. a.Enter 70 for Model Dimension. b.Select MSC.Nastran for Analysis Code. c.Select Structural for Analysis Type. d.Click OK. a b c d
WS9-8 PAT301, Workshop 9, October 2003 Step 3: Import Geometry from an IGES file Import an IGES file a.File / Import… b.Select Model for Object. c.Select IGES for Source. d.Select Anchor.igs for File name. e.Click Apply. f.Click OK in Import Summary window. a b c d e
WS9-9 PAT301, Workshop 9, October 2003 Step 4: View Use icons for viewing a.Click Iso 3 View icon. b.Click Fit view icon. c.Click Smooth shaded icon. d.Click Mouse rotate XY icon and use the middle button of the mouse to rotate as needed. a b c d
WS9-10 PAT301, Workshop 9, October 2003 Step 5: Create First Missing Surface Using Two Edges Create Missing Surface a.Rotate the model as needed to achieve this view. b.Geometry: Create / Surface / Curve. c.Select 2 Curve for Option. d.See Figure for Starting Curve List. e.See Figure for Ending Curve List. b c d e a
WS9-11 PAT301, Workshop 9, October 2003 Step 6: Create Second Missing Surface Use trimmed method to create surface. a.Geometry: Create / Surface / Trimmed. b.Select Planar for Option. c.Click Auto Chain… d.Continue… a b c
WS9-12 PAT301, Workshop 9, October 2003 Use trimmed method to create surface. a.Rotate the model and zoom in as needed to achieve this view. b.See figure for Select a Start Curve. c.Click Next and OK as needed; see next page for detailed picture. Step 6: Create Second Missing Surface (Cont.) Pick any free surface edge to start Patran will select an adjacent congruent surface edge If edge is desired for loop, click OK. If edge is not desired, click Next until desired edge is found, then click OK. b c c a a
WS9-13 PAT301, Workshop 9, October 2003 Step 6: Create Second Missing Surface (Cont.) To navigate around the free surface edges it is necessary to use the Next and OK buttons in the Auto Chain form. a.At the first set of edges encountered (two edges – one vertical and the other horizontal going to the left) Patran chooses the vertical one. This is marked by a magenta colored dot. b.Click Next. This causes Patran to choose the other edge(desired), now marked by a magenta dot. c.This edge is desired, so click OK. d.Continue doing this(using Next and/or OK) until a closed path(set of edges) is specified – back at the starting location. e.Click Cancel. Wrong Edge, So Click Next Correct Edge, So Click OK
WS9-14 PAT301, Workshop 9, October 2003 Step 6: Create Second Missing Surface (Cont.) Use trimmed method to create surface. (Cont.) a.Click in Outer Loop List box. b.Select Curve icon. c.Select Curve 1 for Outer Loop List. d.Click Apply. e.Answer Yes to deleting original curves. b d c a Completed Trimmed Surface
WS9-15 PAT301, Workshop 9, October 2003 Step 7: Delete Unnecessary Internal Surfaces Delete Surfaces that are not to be in the interior of the solid that is being created. a.Geometry: Delete / Any. b.See figure, and select two surfaces for Geometric Entity List(turn off Auto Execute toggle, and use shift key for picking both surfaces). c.Click Apply. a b
WS9-16 PAT301, Workshop 9, October 2003 Step 8: Create Points at Center of Arcs Create point at center of arc for cylindrical coordinate system. a.Geometry: Create / Point / ArcCenter. b.Turn Auto Execute off. c.See figure, select two edges for Curve List. d.Click Apply. a c b d
WS9-17 PAT301, Workshop 9, October 2003 Step 8: Create Cyl Coord System from Center Points (Cont.) Create coordinate system using 3Point method. a.Geometry: Create / Coord / 3Point b.Select Cylindrical for Type. c.Click Wireframe icon and Point size icon(increase Point size). d.See figure for Origin. e.See figure for Point on Axis 3 (Z- axis). f.See figure for Point on Plane 1-3. g.Reduce the Point size and shade the model using the Smooth shaded icon. a b d e f c c g
WS9-18 PAT301, Workshop 9, October 2003 Step 8: Create Curve by Translating Method (Cont.) Create curve by translating surface edge. a.Geometry: Transform / Curve / Translate. b.Select Curvilinear in Refer. CF for Type of Transformation. c.Select Coord 1 for Refer.Coordinate Frame. d.Enter for Translation Vector. e.See figure for Curve List. a b c d e
WS9-19 PAT301, Workshop 9, October 2003 Step 8: Break Surface (Cont.) Break a surface into two surfaces. a.Geometry: Edit / Surface / Break. b.Select Curve for Option. c.See Figure for Surface List. d.Click Curve icon. e.See Figure for Break Curve List. f.Answer Yes when asked the question about deleting original surfaces. a b c d e
WS9-20 PAT301, Workshop 9, October 2003 Step 9: Break Surface by Parametric Use parametric option to break surface for application of pressure on top of hole a.Geometry : Edit / Surface / Break. b.Select Parametric for Option. c.Select Constant v Direction for Break Direction. d.Select 0.5 for Break Curve Parametric Value. e.See figure for Surface List. f.Note: Surface 3 should be broken horizontally. g.Answer Yes to deleting original surfaces. a b c d e
WS9-21 PAT301, Workshop 9, October 2003 Step 9: Add Vertices For Congruency (Cont.) Add vertices so the surfaces will be congruent where Surface 3 was broken. a.Geometry: Edit / Surface / Add Vertex. b.Turn Auto Execute On. c.See figure for Point List. d.See figure for Surface. e.Repeat for the other side using the same steps. a c d e e b
WS9-22 PAT301, Workshop 9, October 2003 Step 10: Mirror Surfaces Mirror surfaces a.Set the display to Iso 3 View. b.Geometry: Transform / Surface / Mirror. c.Click in the Define Mirror Plane Normal, then click 3 points for the plane icon. d.See Figure to select points for Define Mirror Plane Normal. The 3 points selected can be anywhere in the plane. e.Select all surfaces for Surface List. b c d e c a
WS9-23 PAT301, Workshop 9, October 2003 Step 11: Mirror Surfaces Again Mirror surfaces again a.Geometry: Transform / Surface / Mirror. b.Click in the Define Mirror Plane Normal, then click 3 points for the plane icon c.See Figure to select points for Define Mirror Plane Normal. Choose any Points in the plane. d.Select all surfaces for Surface List. a b c d b
WS9-24 PAT301, Workshop 9, October 2003 Step 12: Create B-rep Solid Create B-rep solid from the congruent surfaces. a.Geometry : Create / Solid / B-rep. b.Select all surfaces for Surface List. a b
WS9-25 PAT301, Workshop 9, October 2003 Step 13: Show Just Solid Show just the B-rep. solid a.Click Wireframe icon. b.Click Plot/Erase icon. c.Click Geometric Entity icon in Picking Filter, then click Solid icon. d.Select Solid 1 for Selected Entities. e.Click Erase for All. f.Click Plot to show just the solid. a c c b e d f
WS9-26 PAT301, Workshop 9, October 2003 Step 14: Quit MSC.Patran Quit MSC.Patran a.Select File on the Menu Bar and select Quit from the drop down menu a