Ring Rolling Lab1
In this Lab we will be setting up simple symmetry model type Ring Rolling operation.
1.1 Creating a New Problem
1.2. Process Page
1.3. Simulation Setup
1.4. Object selection
1.4.1. Workpiece-Ring General Page
1.4.2. Driving Roll Object Page
1.4.3. Pressure Roll Object Page
1.5. Contact Page
1.6. Stopping Controls
1.7. Step and Remeshing controls Page
1.8. Simulation controls
1.9. Generate Database
1.10. Running Simulation
1.11. Post Processing
Creating a New Problem
On a Windows machine , go to the 
button select DEFORM-v1x.xxx (.xxx indicates version number E.g. v14.0.2) and select DEFORM GUI Main vxx.xx from the menu. The DEFORM GUI Main window will appear.
Create a new problem either by selecting File
**New Problem** or by clicking the New Problem 
icon. The Problem Setup window will appear as shown in Fig. RRL1.1. Select “ Integrated Manufacturing Process “ radio button and Unit system as “English “ using radio button. Define Problem Name as “RING_ROLL_LAB1 “ and make sure the “Show option dialog” check box is turned on (if we do not turn on the “Show option dialog ” check box, then we will not get the New Project dialog in MO UI). Then click on 
button to open a new Problem using the Deform Integrated Manufacturing Process.
New Problem page
Multiple operation wizard will open with the New Project dialog, at this point user will be prompted to specify a project name (system will create a separate folder with this project name) and title for this session. In this session we will use ‘RING_ROLL_LAB1 ’ as the project name. 3D Ring Rolling operation can also be added in “New Project” dialog (see Fig. RRL1.2.), in this lab we will add Ring rolling operation from Explorer operation list, so do not check “First operation” check box and “ Ring Rolling” operation in “New Project” dialog. Click on to continue to open the operation.
Add 3D Ring Rolling operation from the Explorer Operations list. Add the operation by clicking on 
button available next to 3D Ring Rolling or user can also add by drag and drop into the Operation editor (See Fig. RRL1.3.). When we add the Ring Rolling operation, process settings window will open by default.
Adding Ring rolling operation from New Project
Adding Ring rolling operation from Explorer
Process Page
In Process page by default “Ring rolling (default) “ radio button will be selected (See Fig. RRL1.4.). Click on 
to Simulation setup.
Process page
Simulation Setup
Select “Symmetry “ 3D model type radio button and keep default Thermal calculation type as “Constant temperature (isothermal) “ in Simulation setup page as shown in Fig. RRL1.5. Click on until Objects page.
Simulation setup page
Object selection
In “Objects ” page, we will use the current default objects as shown in Fig. RRL1.6. Minimum of 3 objects workpiece (Ring), Pressure roll (mandrel) and driving roll are required to set up a simple ring rolling operation. In this lab we will not using any axial roll. Click on to Workpiece - Ring page to define Ring object.
Objects list for Symmetry model
Workpiece-Ring General Page
In Workpiece-Ring page define the Object temperature as 70F as shown in Fig. RRL1.7, the default object type for workpiece (Ring) is plastic. In this lab we will create workpiece hence we will leave the default values as shown in Fig. RRL1.7. Click on to 2DCross- section page.
Extract cross-section from 3D shape
In case user is importing the object from a file then Axis/Center can be calculated using the 
button and Extract cross-section will be enabled so that user can extract cross-section of the imported object (See Fig. RRL1.8.). From the imported object user can extract single cross-section from a particular layer using “Extract cross-section at layer no” or user can extract multiple cross-section from different layers in case of non-uniform ring and use the average size as cross-section using “Extract Cross-section from Layers and use their average”.
Workpiece-Ring page
Extract cross-section page
Workpiece-Ring 2D cross-section Page
In Workpiece 2D cross-section page, click on 
and define the co-ordinates data as shown in Fig. RRL1.9. Click on 
to close the Edit Window and click on to 2D Mesh page. In 2D Geometry page user has also options to import 2D cross-section using 
button from a file or using 
button from library.
| X | Y | R |
|---|---|---|
| 4 | 3.25 | 0 |
| 4.75 | 3.25 | 0 |
| 4.75 | 4.5 | 0.062 |
| 3.75 | 4.5 | 0.03 |
| 3.75 | 3.25 | 0 |
| 4 | 3.25 | 0 |
Workpiece edit geometry page
Workpiece 2D Geometry page
Workpiece-Ring 2D Mesh Page
In 2D mesh settings, define Target Number of Elements as 80 and click on 
button and observe the generated mesh in Mesh window (See Fig. RRL1.11.). Expert mode is available for the user in case of complex ring geometries to define advanced mesh conditions like mesh windows, change weighing factors,..etc as shown in Fig. RRL1.12. Click on to 3D Geometry page.
Workpiece 2D Mesh page - Guided mode
Workpiece 2D Mesh - Expert mode
Workpiece-Ring 3D Geometry Page
In 3D Geometry page, click on “Revolve from 2D “ option (See Fig. RRL1.13.), use the default values in Revolve from 2D page and Click to close. If user has loaded a 3D geometry of the workpiece from a file, then Extract cross-section option can be used to extract the cross-section from the 3D Geometry and use it to revolve into 3D Geometry. Click on to 3D Mesh page.
Workpiece- Ring 3D Geometry page
Workpiece-Ring 3D Mesh Page
In 3D Mesh page we have options to create mesh with uniform cross-section or to fit 3D Shape in case of workpiece having non-uniform cross-section. For this lab we will use default value of 120 for “ Number of Revolving sections “ and generate 3D mesh by clicking on . Observe the generated 3D Mesh for workpiece is should looks like as Fig. RRL1.14. Click on to Workpiece Orientation page.
Workpiece-Ring 3D Mesh Page
Workpiece Orientation
Workpiece is at 0 angle from object axis to +Z axis, so no need to position the Workpiece (See Fig. RRL1.15.), click on to Workpiece Material page.
Workpiece orientation page
Assign Workpiece-Ring Material
In Material page, click on (Load material from library) icon and load the material steel group material “ AISI-5135H,COLD[70-550F(20-300C)] “ from material library window. Assign the “AISI-5135H,COLD[70-550F(20-300C)] “ material by selecting it for Workpiece. Click on to Workpiece BCC page.
Assign BCC for Workpiece-Ring
Check the default Symmetry BCC assigned for workpiece, default symmetry BCC should be assigned for Symmetry surface as shown in Fig. RRL1.16. Click on until Driving Roll Object page.
Workpiece-Ring Boundary condition page
Note on Ring Rolling operation added as second operation in batch mode:
Ring Rolling operation can be added as second operation in batch mode after pre-forming ring using Forming operation or after heat transfer operation. In such case, user can regenerate the ring by checking Regenerate ring check box (see Fig. RRL1.17.). When user checks” Regenerate Ring “ check box, “Extract cross-section” page is added and can be accessed using button from the workpiece object page. User can extract the cross-section geometry for 2D cross-section mesh using options from extract cross-section page of workpiece object, the options available are shown in Fig. RRL1.18.
User can extract single cross-section using “Extract One cross-section” option from “Constant Cross section” tab. If user wants single cross-section from multiple layers of non-uniform ring then user can extract multiple cross-sections from different layers and use the average size as cross-section using “Extract multiple Cross sections from Layers and use their average” option.
User can extract multiple cross-sections and retain them to generate non-uniform ring using “Extract multiple Cross sections from Layers” option from “Variable Cross-section” tab
When user regenerates Ring in batch mode then the Ring is automatically aligned to Z-axis and the X co-ordinate of its center is moved to ‘0’, if user does not regenerate ring then the Ring will be aligned to Z-axis without modifying Ring center co-ordinates.
Read from DB Workpiece General page
Read from DB workpiece Extract cross-section page
Driving Roll Object Page
Keep the name of Driving roll unchanged and just click to go to the 2D cross-section geometry page.
Driving roll 2D cross-section Page
In Driving Roll Geometry page, click on and define the co-ordinates data as shown in Fig. RRL1.19. Click on to close the Edit Window and click on to 3D Geometry page.
| X | Y | R |
|---|---|---|
| 0 | 1.25 | 0 |
| 5 | 1.25 | 0 |
| 5 | 1.9875 | 0.025 |
| 4.66 | 2 | 0.093 |
| 4.66 | 4.5 | 0.093 |
| 5 | 4.525 | 0.025 |
| 5 | 5.25 | 0 |
| 0 | 5.25 | 0 |
Driving Roll 2D Geometry page
Driving Roll 3D Geometry Page
In 3D Geometry page, click on “Revolve from 2D “ option, use the default value of 100 for “Number of layers in hoop direction “ in Revolve from 2D page and Click to close. Click on to Orientation page.
Driving Roll orientation
When we visit Orientation page by default Rolls will be in interference position with Workpiece, now the Workpiece and Rolls are in correct position so no need to do position. So, click on to Movement page.
The orientation page can be used to position the Driving Roll along the axis by specifying the distance with respect to the object centers or distance between the objects bottom faces, see Fig. RRL1.20.
Driving Roll orientation page
Driving roll movement
Select Angular velocity in rotation movement controls for the driving roll and define a constant value of 20.943 rad/sec. Notice a green rotation arrow showing rotational direction in the display window (See Fig. RRL1.21.). Click on to Object page of Pressure roll.
Driving Roll Movement page
Pressure Roll Object Page
Keep the name “Pressure Roll” unchanged and just click on to go to the 2D cross-section page.
Pressure Roll 2D cross-section Page
In Pressure Roll 2D Geometry page, click on and define the co-ordinates data as shown in Fig. RRL1.22. Click on to close the Edit Window and click on to 3D Geometry page.
| X | Y | R |
|---|---|---|
| 0 | 0 | 0 |
| 2 | 0 | 0 |
| 2 | 1.975 | 0.025 |
| 1.62 | 2 | 0.093 |
| 1.62 | 2.75 | 0 |
| 1.75 | 3.25 | 1.5 |
| 1.62 | 3.75 | 0 |
| 1.62 | 4.5 | 0.093 |
| 2 | 4.525 | 0.025 |
| 2 | 6 | 0 |
| 0 | 6 | 0 |
Pressure Roll Geometry page
Pressure Roll 3D Geometry Page
In 3D Geometry page, click on “Revolve from 2D “ option, Use the default value of 100 for “Number of layers in hoop direction “ in Revolve from 2D page and Click on to close. Click on to Orientation page.
Pressure Roll orientation
Now the Workpiece and Rolls are in correct position so no need to position. So, click on to Movement page.
The orientation page can be used to position the Pressure Roll along the axis by specifying the distance with respect to the object centers or distance between the objects bottom faces, see Fig. RRL1.23.
Pressure roll orientation page
Pressure roll movement
We will define Pressure Roll movement Speed as “Function of time “ as shown below table and Fig. RRL1.24. Click on until Contact page.
| Time | Speed |
|---|---|
| 0 | 0.03 |
| 5 | 0.03 |
| 15 | 0.015 |
| 20 | 0.015 |
Pressure Roll Speed as Function of Time Movement
Contact Page
In Contact page, use the default shear friction value and click on 
to generate contacts between driving roll and the workpiece as well as between pressure roll and the workpiece (See Fig. RRL1.25.). Click on to Stopping controls page.
Contact page
Stopping Controls
Select Primary die as “Pressure roll (Mandrel) “and define the Y displacement value as “0.375 “ under Max. primary die displacement as shown in Fig. RRL1.26. Click on to define Step and Remeshing controls page.
Stopping controls page
Step and Remeshing controls Page
Enter Number of steps as 20000 , Rotation increment to save as 360 and Max allowed time step as 0.02. Use default Remeshing control as shown in Fig. RRL1.27., user can turn on this option to remesh object after specified number of revolutions to maintain good workpiece shape in case of complex geometries. Click on to Simulation controls.
Step and Remeshing controls page
Simulation controls
In this page, user can define constraints to the workpiece center as shown in Fig. RRL1.28. checking respective check box.
User can also add a virtual table at top or bottom by checking respective check box and specifying the distance of virtual table location from top / bottom surface.
Using advanced settings from Advanced Control tab, user can define the frequency of steps to verify for node penetration in case user observes heavy penetration into rolls. User can also specify angle for contact search to improve the Solution speed.
If the ring object is not rotating properly then user can check “Enforce to rotate workpiece when it does not rotate well at certain steps” to make small corrections to the ring rotation during the ring rolling process.
The data defined in this page will be written to DEF_RRE.DAT file.
In this lab we will use the default settings and click on to Generate DB page.
a. Stability controls
b. Advanced controls
Simulation controls
Generate Database
In Generate DB page, click on the 
button to generate the database. Observe the message in Message tab informing database generation status.
Running Simulation
Once the database has been generated, switch to the Simulation mode by selecting the 
button above the object tree. Click on the 
action label to open the Run Options dialog as shown in Fig. RRL1.29. Use the default Continue Run option to select “Continue from the last step ” (from step -1) option and then select the Simulation mode as Interactive and click on 
button to run the simulation.
Run Simulation Window
Monitor the progress of the simulation by looking at the Simulation Message and Simulation Log tab, making sure that the 
option is checked. User can view the Ring Rolling process as the simulation proceeds to the specified stopping criteria from Simulation graphics.
Post Processing
When the simulation is completed with ‘normal stop’, review the results by switching to Post mode using the 
button above the Simulation tool bar.
Play through the steps of the simulation and look how the workpiece-Ring is formed.
Click on 3D Mirroring and add symmetry on the symmetry plane of the Workpiece - Ring.
Click on 
Single object mode by selecting workpiece-Ring and plot Effective Strain and Effective Stress of the workpiece-Ring. When we play through the steps, we can observe the increase in strain value. The Effective strain and Stress value at the end of the simulation should look like as shown in Fig. RRL1.30.
Showing the effective strain and effective stress
Showing the ring after completion of simulation
The below Fig. RRL1.32. shows the initial and final dimensions of the ring. The user can make out the difference in ring diameter at the end of the simulation.
Initial and Final Dimensions of the ring.
Final Cross section of the ring is as shown in below Fig. RRL1.33. and Fin defect in Ring rolling is as shown in Fig. RRL1.34.
Showing the Cross Section Thickness after completion of simulation at various curvatures.
Showing Fin Defect in Ring Rolling