1. Single Product Model for Transmission Design & Analysis
RomaxDesigner

2. About this Presentation
Aims of the presentation
Modelling the components:
shafts
bearings
gears
Assembling the gearbox
Defining the loads and powers
Running the analysis
Review of the results and further RomaxDesigner capabilities
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3. Introduction Aims of this presentation are to show how:
To model an existing transmission in just one day
To analyze the model for shaft, bearing and gear performance and life
To use the analysis results to optimize an existing design
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4. Modelling the Transmission
Key Stages for Creating a RomaxDesigner Model
Definition of components
Mounting the gears on to shafts
Definition of gearbox internal geometry
Powerflow definition and analysis
Review of results
Options for further analysis and optimization
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5. Modelling the Transmission
RomaxDesigner Modelling stages:
Definition of components
Mounting the gears on to shafts
Definition of gearbox internal geometry
Powerflow definition and analysis
Review of results
Options for further analysis and optimization
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6. Modelling the Transmission
The first step is to create a shaft by simply selecting it from the menu:
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7. Modelling the Transmission
Specify the approximate shaft outer dimensions:
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8. Modelling the Transmission
To create shaft sections of different sizes, use the cutter icon to define steps:
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9. Modelling the Transmission
Specify the dimensions of each section including any tapers and bores if needed:
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10. Modelling the Transmission
The user need only input the geometry
RomaxDesigner will generate static and dynamic models from this data instantaneously
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11. Modelling the Transmission
RomaxDesigner automatically generates a solid model and 3-D view for easy visualization:
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12. Modelling the Transmission
To add bearings, select the bearing icon and click at the approximate position:
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13. Modelling the Transmission
RomaxDesigner has complete bearing database catalogues for SKF and FAG to choose from - as well as a Custom specification option:
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14. Modelling the Transmission
View the details of a range of bearings and accept the most suitable:
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15. Modelling the Transmission
Every bearing is a fully specified engineering object ready for analysis:
Virtual Component has :
- Dimensions
- Engineering Properties
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16. Modelling the Transmission
Specify its exact position on the shaft, and conditions such as axial constraints and pre-load:
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17. Modelling the Transmission
Repeat the procedure to add further bearings:
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18. Modelling the Transmission
The 3-D view is updated automatically:
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19. Modelling the Transmission
To add gear pairs there are two options for defining gear geometry:
Concept gear pair
Basic gear data required for the calculation of forces on the shafts and bearings
Detailed gear pair
Requires additional macro-geometry data for gear rating
Concept - quick check, allows fast progress with confidence that can detail later if the model looks promising FOR RATIO AND CALCULATION OF LOADS ON THE SHAFTS
Detail - the full model, mainly an automated generation, the exact design and all attendant details required for full analysis are specified uniquely by just a few variables - once again rapid results
DETAILED DESIGN AND RATING TO ISO 6336 AND AGMA 2001
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20. Modelling the Transmission
Create a new concept gear pair:
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21. Modelling the Transmission
Detail the concept pair if full analysis results are required:
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22. Modelling the Transmission
A completed detailed gear pair:
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23. Modelling the Transmission
Mount the gear on the shaft with the gear icon:
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24. Modelling the Transmission
Create and connect more gears to complete the shaft:
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25. Modelling the Transmission
The completed solid model of the shaft in 3-D:
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26. Modelling the Transmission
RomaxDesigner automatically produces a static model:
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27. Modelling the Transmission
And a dynamic model to completely simulate the behaviour of the shaft:
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28. Modelling the Transmission
RomaxDesigner Modelling Areas:
Definition of components
Mounting the gears on to shafts
Definition of gearbox internal geometry
Powerflow definition and analysis
Review of results
Options for further analysis and optimization
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29. Modelling Overview Gear mounting definition
There are four options for defining gear mounting in the model:
Integral with shaft
The gear is manufactured into the shaft
Rigidly mounted to shaft
The gear is permanently attached to the shaft
Synchronizer or clutch connection
The gear is free to rotate on the shaft unless the synchroniser/clutch is engaged
Free Rotation
The gear is free to rotate on the shaft
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30. Modelling the Transmission
Selection of gear mounting method:
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31. Modelling the Transmission
Define the details of the gear blank for inertia calculations:
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32. Modelling the Transmission
RomaxDesigner Modelling Areas:
Definition of components
Mounting the gears on to shafts
Definition of gearbox internal geometry
Powerflow definition and analysis
Review of results
Options for further analysis and optimization
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33. Modelling the Transmission
Once the other shafts have been generated, their relative positions need to be specified:
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34. Modelling the Transmission
The completed gearbox:
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35. Modelling the Transmission
The completed solid model is ready for analysis:
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36. Modelling the Transmission
RomaxDesigner Modelling Areas:
Definition of components
Mounting the gears on to shafts
Definition of gearbox internal geometry
Powerflow definition and analysis
Review of results
Options for further analysis and optimization
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37. Defining the Load Conditions
Add input and output power loads with the power load icon:
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38. Defining the Load Conditions
Define the time and clutch/synchro for each speed:
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39. Defining the Load Conditions
Define the loads for each speed:
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40. Defining the Load Conditions
The completed duty cycle with six defined speeds, ready to run:
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41. Defining the Load Conditions
The duty cycle results on all components are calculated in under a minute on a standard PC:
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42. Modelling the Transmission
RomaxDesigner Modelling Areas:
Definition of components
Mounting the gears on to shafts
Definition of gearbox internal geometry
Powerflow definition and analysis
Review of results
Options for further analysis and optimization
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43. Review of Results
RomaxDesigner calculates complete duty cycle results, in under a minute, on a standard PC
The results for each load case include:
Forces, moments, displacements and stresses for all shafts
Deflections, tilts and displacements on all bearings
Mesh misalignment for all gear meshes
Life rating for all bearings and gears including misalignment effects
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44. Review of Results
The results for a single load case will be examined first:
Shaft loadings and deflections leading to bearing rating and gear mesh misalignment
Then the cumulative effect of the duty cycle will be shown
This gives a final assessment of gear and bearing performance for the specified duty cycle
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45. Results for a Single Load Case
The input shaft forces in 1st speed in the x-direction:
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46. Results for a Single Load Case
The input shaft shear force diagram in 1st speed in the x-z plane:
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47. Results for a Single Load Case
Input shaft moments in 1st speed in the x-z plane:
Moment from the bearing arises from the calculated tilt stiffness
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48. Results for a Single Load Case
Input shaft displacements in 1st speed in the x-direction:
The bearing displacement is non-zero
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49. Results for a Single Load Case
Input shaft bending stresses in 1st speed:
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50. Results for a Single Load Case
Bearing results showing the life, as well as the relative and absolute displacements:
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51. Results for a Single Load Case
Bearing results showing the bearing stiffnesses:
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52. Results for a Single Load Case
Shaft deflections are converted into gear mesh misalignment:
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53. Results for a Single Load Case
The life rating for the gear pair is then calculated to ISO 6336 or AGMA 2001:
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54. Results for a Single Load Case
The user can choose to include the effect of misalignment in the gear rating:
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55. Duty Cycle Results
For each component, the duty cycle result includes a contribution from each load case:
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56. Duty Cycle Results
Complete ISO life and the Adjusted life (which includes the effect of misalignment on bearings):
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57. Duty Cycle Results Also duty cycle results for the gear pair :
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58. Modelling the Transmission
RomaxDesigner Modelling Areas:
Definition of components
Mounting the gears on to shafts
Definition of gearbox internal geometry
Powerflow definition and analysis
Review of results
Options for further analysis and optimization
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59. Further Analysis (i) Examples of additional work possible
using the RomaxDesigner software:
The influence of Housing Stiffness on the system deflections
The misalignment of synchronized gears mounted on needle roller bearings
Stress concentration factors and shaft fatigue analysis.
- Defining gear trains including reverse -
- The effect of housing stiffness derived from FEA data
- How is the cycle more detailed? (MORE LOADCASES, E.G. 5TH SPEED 100%, 80% ETC. TORQUE).
Conclusion needed.
CONCLUSIONS SHOULD BE:
Modeling OF THE COMPLETE GEARBOX IN LESS THAN 1 DAY
DUTY CYCLE ANALYSIS OF GEARBOX IN LESS THAN 1 MINUTE
WORLD-LEADING ANALYSIS IN AN EASY-TO-USE INTERFACE
SPEED-OF-USE ALLOWS DESIGN Optimization
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60. Further Analysis (ii) Examples of additional work possible
using the RomaxDesigner software:
A more detailed duty cycle, e.g. for different driving styles and conditions
Gear micro-geometry definition and transmission error calculation
Synchronizer sizing and simulation.
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61. Further Analysis (iii)
Examples of additional work possible
using the RomaxDesigner software:
Driveline dynamic analysis and NVH
Perpendicular shafts, hypoid, spiroid and bevel gears
In-depth analysis of bearings.
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62. Conclusions RomaxDesigner allows:
Modelling of a complete gearbox … in less than 1 day
Duty cycle analysis of a gearbox … in under 1 minute
World-leading analysis in an easy-to-use interface
This speed-of-use allows rapid iterative design optimization for the first time
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63. Your Next Step! Thank you for reviewing RomaxDesigner.
You may now wish to:
Start using RomaxDesigner
Take one of the Romax in-depth training courses on transmissions, or gear design using RomaxDesigner ( us - see next slide)
Contact Romax for more details on Romax software solutions (see next slide)
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64. For more information contact:
Romax Technology Limited Rutherford House
Nottingham Science and Technology Park
Nottingham
England, NG7 2PZ
Tel: +44 (0)
Fax: +44 (0)