FEM-Analysis of a Column Crane with FEM-System MEANS V10. Website: Phone:

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1 FEM-Analysis of a Column Crane with FEM-System MEANS V10 Website: info@fem-infos.com Phone:

2 Part 19: FEM-Analysis of a Column Crane with MEANS V10 1 Part 19: FEM-Analysis of a Column Crane with MEANS V10 Column Crane Calculate the deformation, v.mises stress, reaction force and the weight when the crane is loaded with its own weight and additional loaded of 1 ton weight load. Start MEANS V10 by a double click on the desktop icon of MEANS V10. Select "New Project" and "3D tetrahedral mesh generation" to the CAD file select the 3D mesh generator.

3 Part 19: FEM-Analysis of a Column Crane with MEANS V10 2 3D Mesh Generator Select the view bar icon and the drop-down-menu "3D Tetrahedral Mesh Generator": A dialog box with the CAD formats appears: STL STEP IGES is a flexible and common CAD format from the outer shell is available at the time of default and in almost any 3D CAD is one of the older CAD formats also there are DXF AutoCAD format for bar and line models, can imported in the Line Mode or in MEANS SHELL

4 Part 19: FEM-Analysis of a Column Crane with MEANS V10 3 It is not possible to mesh the CAD model following options are available: Check in the CAD system all solids and surfaces with unconnected edges and holes, very small extrusions or intersections and delete, optimize or repair them. If there is a assembly with many single parts then it must be united in the CAD system to create a complete model with only one part. For smaller assemblies use "FreeCAD" with menu "Create Step-Assembly". Convert with menu "SAT-STEP Converter" SAT files or other into the STEP or IGES format. The CAD Converter is a demo version with a long runtime of 60 days. Another way still to mesh the CAD model with the same CAD file would be optimized with various repair tools from HTA-Software. This service is under a support contract free of costs.

5 Part 19: FEM-Analysis of a Column Crane with MEANS V10 4 Mesh Generator No. 2 Select the STP file "Column-mounted slewing crene.stp" and select "Start Mesh Generator No. 2". It automatically starts the mesh generator and the CAD model is showing in a windows frame. You can rotate, scale and pan it with the three mouse buttons. Generate a FEM Mesh Generate the FEM-Mesh with "Generate Mesh" with the default mesh density "moderate" to a FEM-Modell with nodes and tetrahedral elements. Export FEM-Mesh with "test.fem" Now select menu "File" and "Export Mesh" to export the mesh under the name test.fem" in the directory path "Debug\Mesh". Now MEANS V10 starts automatically with the FEM model. If the FEM mesh not automatically started with MEANS V10 then it can loaded as a structure file "test.fem" also from the mesh directory.

6 Part 19: FEM-Analysis of a Column Crane with MEANS V10 5 Create a Surface Model Choose menu Generate Surface Model in order to create a surface model for selecting surfaces for loads and boundary conditions. Also you can show or hide the surfaces. Select moderate and create the surface model with 78 surfaces.

7 Part 19: FEM-Analysis of a Column Crane with MEANS V10 6 Create Load case 1 The crane is loaded with a weight load of 1 ton or N plus dead weight. Load case 1 can be created either as a point load or as a surface load. Point Load or Surface Load Point Load Select menu Point Loads and menu Step 2: Create Point Load and input the values: Actual Load Case = 1 Number of Loads = 0 Load value = - 1, because number of loads is still unknown Direction = Z direction Selection: Surface Modus Select Create Point Load and double click on surface 19. This surface is displayed in the selectbox there choose Create to create a point load with 50 nodes.

8 Part 19: FEM-Analysis of a Column Crane with MEANS V10 7 Calculate the Load value Select Edit FEM Project and Point Loads / Surface Loads and select menu Load Factor and calculate the Load Factor with the difference of Weigh Load / Number of Loads Load Factor = N / 50 = N

9 Part 19: FEM-Analysis of a Column Crane with MEANS V10 8 Input the Load Factor -200 with replace and select OK.

10 Part 19: FEM-Analysis of a Column Crane with MEANS V10 9 Calculate Cross-Sectional Area Load case 1 may alternatively be generated with a surface load. Since only the weigh load is known must first be determined the cross-sectional area of surface 19 to calculate the value of the surface load. Select menu Surface Loads and Step 2: Calculate Cross-Sectional Area. In the new dialog box all surface areas are displayed and sorted by cross-sectional area. Select menu "Hide All Surfaces" and display only area of surface 19. Activate "Calculate Total Area " and enter a total load of N so a surface load of MPa is calculated.

11 Part 19: FEM-Analysis of a Column Crane with MEANS V10 10 Create a Surface Load Select menu Surface Loads and Step 3: Create Surface Load and enter a surface load of vertical to Surface. Select Create Surface Loads and double click to surface 19. Surface 19 is displayed in the select box, there choose Create to enter the surface load.

12 Part 19: FEM-Analysis of a Column Crane with MEANS V10 11 Create Own Weight Load Select the icon menu and menu "Gravitation Loads" and enter Load Case 2 with a gravitational acceleration of "-9.81" in Z-direction. After select "Create only Load Case (Quick solver)" because the FEM Solver combine both load cases automatically. In the Dr.Kühn solver, however, a load case superposition must be generated.

13 Part 19: FEM-Analysis of a Column Crane with MEANS V10 12 Create Boundary Conditions The crane is clamped fixed on its column. Select menu "Create Boundary Conditions and "Step 2: Create Boundary Conditions and choose in the next dialog box Create BCs and double click on the surfaces 31 and 50.

14 Part 19: FEM-Analysis of a Column Crane with MEANS V10 13 Input Material Datas Select the menu Edit FEM Project and Material Datas and input the material datas for steel. Select Material Date Base and take up the material steel in the material data box.

15 Part 19: FEM-Analysis of a Column Crane with MEANS V10 14 FEM Analysis First, save the FEM model under any name in the current project directory and select "FEM analysis" and again "FEM analysis". In the next dialog box, click on to the "Quicksolver" and "Step 1: Start FEM solver". Select "Start FEM-Solver with INP-Interface" to close MEANS V10 automatically and to start the FEM Solver. After the calculation select "Start Postprocessing MEANS V10" to start MEANS V10 with the FEM model.

16 Part 19: FEM-Analysis of a Column Crane with MEANS V10 15 Postprocessing Choose the menu Postprocessing to evaluated the results. v.mises-stresses Please select following Settings: Results: Nodal or Element Stress Contour Load Case: 2 Edit Accuracy: 4 Result Component: von Mises Stress

17 Part 19: FEM-Analysis of a Column Crane with MEANS V10 16 Max. v.mises-stresses= MPa Increase accuracy Compare the results of the nodal stresses with the higher element stresses (see Handbook Part 2, Page 25) For a better result, use the TET4X8 element that can automatically divided the TET4 element into 8 smaller tedrahedrons so the FEM mesh is 8x finer and very fast. TET4X8 is only available in MEANS V10. Use the quadratic tetrahedral element TET10 with additional middle nodes Runtime: 30 seconds 3 minutes 30 minutes

18 Part 19: FEM-Analysis of a Column Crane with MEANS V10 17 Displacements Please select following Settings:: Results: Nodal or Element Stress Contour Load Case: 1 Edit Accuracy: 1 Result Component: von Mises Stress Max. Displacements in Z direction = mm Displacement Factor Select Structure with and without Displacements Calculate a Displacement Factor of Set down the Range of Values when you have high peak stresses or abnormal stresses and deformations caused by badly tetrahedral elements.

19 Part 19: FEM-Analysis of a Column Crane with MEANS V10 18 Search Values Further select Picking Stress Values and define a value of 30 until a value of 40 with the unsigned and absolute values. Choose Search and click to the last value in the listbox to show the value directly on the displacement contour.

20 Part 19: FEM-Analysis of a Column Crane with MEANS V10 19 Check Sum of Reaction Forces First select Contour of Forces in z direction. Contour of the Forces in z direction:

21 Part 19: FEM-Analysis of a Column Crane with MEANS V10 20 Select Pick, Search and Save Values and Sum of Forces in order to show the sum of all node forces and the sum only of the reaction forces in z direction. Load Case 1: Sum of Reaction Forces in z direction = N (= 1 ton) Load Case 2: Sum of Reaction Forces in z direction = N Calculate Weight The weight can be calculated from the difference between the two load cases or run a new FEM analysis with only weight load by: Weight load = N Weight = Kg The crane has a weight of Kg.