Oil leakage and power loss from radial shaft seals used in automotive power transmission systems
Lead Research Organisation:
Loughborough University
Department Name: Wolfson Sch of Mech, Elec & Manufac Eng
Abstract
Radial shaft seals are frequently used in power transmission systems to prevent oil leakage. The importance of these components for operational reliability provides a great challenge for the industry. Pertinent design and standardisation of key surface parameters such as surface texture and machine lead angle or shaft lead are paramount. The former is an inherent property of any surface, which is also commonly referred to as surface roughness whilst the latter is formed during manufacture of the shafts.
The often contradictory objectives of efficiency, effective sealing and reliability require a combined numerical and experimental approach. A numerical model accounting for surface interactions and hydrodynamic flow in the mixed regime of lubrication will be created. The numerical model will be used to understand the underlying physics and inform design. In parallel, a component level test rig will be created to experimentally validate the numerical model and to benchmark new components designs. Additionally, new standards will be created to characterise the waviness and roughness of the contact surfaces measured using optical interferometers.
The often contradictory objectives of efficiency, effective sealing and reliability require a combined numerical and experimental approach. A numerical model accounting for surface interactions and hydrodynamic flow in the mixed regime of lubrication will be created. The numerical model will be used to understand the underlying physics and inform design. In parallel, a component level test rig will be created to experimentally validate the numerical model and to benchmark new components designs. Additionally, new standards will be created to characterise the waviness and roughness of the contact surfaces measured using optical interferometers.
| Description | Radial lip seals are a commonly used sealing solution for transmission systems used in automotive industry. Performance of a radial lip seals depends on both seal material characteristic (geometry, Young modulus, wear behaviour and surface roughness) as well as on a counter-face topography -in this case steel shaft. The first key founding of this project relates to current standardised roughness values required for the successful operation of the seal. It has been shown that mean roughness value and maximum range of roughness does not give enough information about the surface and shafts with same Ra and Rq can either perform successfully or fail. Another roughness parameter, skewness was identified as potentially crucial and needed to be adjusted to the right level for reliable function of the seal. |
| Exploitation Route | The finding can be utilised by the industry companies manufacturing shafts- by implementing skewness checks of the shaft surface roughness as the most cost effective way to maintain quality of their products at the highest standard. Researchers working within tribology field can also find these findings useful for any other applications where surface topography is investigated. |
| Sectors | Aerospace, Defence and Marine,Energy,Manufacturing, including Industrial Biotechology,Transport |
| Description | Neapco Europe partnership |
| Organisation | Neapco Europe GmbH |
| Country | Germany |
| Sector | Private |
| PI Contribution | Provision of 3D surface topography analysis of the product samples provided by the collaborator. Identification of parameters playing crucial role in performance of the product and sharing this information with the collaborator. |
| Collaborator Contribution | Providing training and product samples. |
| Impact | This collaboration is focused on a specific application of collaborator's interest. The clear outcomes will be known by the end of this award. |
| Start Year | 2017 |
| Description | Attendance at Powertrain and Modelling Conference, Loughborough University |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Industry/Business |
| Results and Impact | As a second author of the paper published as conference proceedings, the attendance at this conference played mainly role of support to the first author who presented the research outcomes. |
| Year(s) Of Engagement Activity | 2018 |
| Description | Presentation at 20th International Sealing Conference in Stuttgart |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Industry/Business |
| Results and Impact | Presentation opened discussion about research approach and possible routes for further development/investigation within the subject. |
| Year(s) Of Engagement Activity | 2018 |
| Description | Presentation at the 24th International Conference on Fluid Sealing 2018 |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Industry/Business |
| Results and Impact | Presenting the research and outcomes to international audience of academics and industrial representatives. The presentation opened a general discussion about the problem and potential ways of solving it/further investigations. |
| Year(s) Of Engagement Activity | 2018 |