Ellen Bergseth - Academia.edu (original) (raw)
Papers by Ellen Bergseth
Transportation Research Procedia, Dec 31, 2022
Tribology transactions, Jul 11, 2016
Proceedings of the Third International Conference on Railway Technology: Research, Development and Maintenance, Mar 10, 2016
The wheel-rail system operates in an open environment where the weather condition varies constant... more The wheel-rail system operates in an open environment where the weather condition varies constantly. In this laboratory study, an investigation using a pin-on-disc tribometer placed in a temperatur ...
Three railway brake block materials, i.e. cast iron, sintered and organic composite, were tested ... more Three railway brake block materials, i.e. cast iron, sintered and organic composite, were tested against railway wheel at10, 3, -10, -20 and -30 °C using a pin-on-disc tribometer with regards to th ...
Tribology International, Aug 1, 2021
Abstract This paper investigates the resistance of micropitting on two materials, using an FZG ba... more Abstract This paper investigates the resistance of micropitting on two materials, using an FZG back-to-back test rig with C-PT gears. The materials are wrought steel (16MnCr5) and a commercial powder metallurgical material (Astaloy™ Mo). Two finishing methods were studied: grinding and superfinishing. Experimental results show that the superfinishing prevented micropitting, but led to premature failure due to cracks in the root caused by tip-to-root interference. Micropitting was initiated at a higher load stage for the powder metallurgical steel compared to the ground wrought steel. The failure mechanisms were similar between materials with the same surface finish. The powder metallurgical steel showed subsurface initiated fatigue compared to the wrought ground steel having surface-initiated fatigue. Testing new finishing methods and materials, one has to be aware of the influence of the gear micro geometry.
Tribology Letters, Jul 20, 2012
Wear, Sep 1, 2015
ABSTRACT
Tribology International, Feb 1, 2018
The main objective of this study is to review the last decade of experimental work in the field o... more The main objective of this study is to review the last decade of experimental work in the field of gear pitting life andefficiency of an FZG gear test rig. Located at KTH Machine Design, the FZG ri ...
Study of surface roughness and surface orientation onfriction in rolling/sliding contacts : barre... more Study of surface roughness and surface orientation onfriction in rolling/sliding contacts : barrel-on-disc versustwin-disc
IQ-steel is isotropic (i.e. equally strong in all directions), cleaner, and with less inclusions ... more IQ-steel is isotropic (i.e. equally strong in all directions), cleaner, and with less inclusions than 16MnCr5 regular gear steel (RS). IQ-steel is used in diesel inlets and for bearings but to date ...
Lubrication science, Oct 1, 2008
Tribology Letters, May 28, 2020
Tribology transactions, Apr 15, 2019
Tribologia - Finnish Journal of Tribology
The ability to stop a gear fatigue test before catastrophic failure has many advantages. However,... more The ability to stop a gear fatigue test before catastrophic failure has many advantages. However, today, a widely accepted approach is not available. This case study applies a vibration-based condition monitoring methodology to detect early gear failures. The gear studied takes part in an all-wheel-drive drivetrain system. Vibration signals from four run-to-failure fatigue tests at two constant torque-speed combinations were used as input to time-synchronous averaging and autoregression model generation. The applied methodology shows promising results for early failure detection, and the process is feasible for implementation in an automated environment. Real time analysis is also possible since the autoregression model generates a healthy state TSA signal during the early testing stages. However, the time to failure detection varies with operating conditions, with low sensitivity at high-speed and low-torque conditions.
2017 International Conference on Mechanical, System and Control Engineering (ICMSC), 2017
This paper introduces the assembly feature data schema instance modeling to pre-examine the schem... more This paper introduces the assembly feature data schema instance modeling to pre-examine the schema functionality and output-as the preliminary step for data modeling. In order to link assembly with product design, it is essential to determine which entities of product design are involved at the automated assembly planning and operations. It is possible to assign meaningful attributes (assembly features) to the part model entities in a systematic and structured way. Using object-oriented design, the assembly feature data structure and its relationships are modeled. As a part of the research on product and assembly system data integration within the evolvable production system platform, the instance models for proposed assembly feature data structure provide a deeper understanding and error reduction that might possibly occur at the development of the database. Moreover through instance modeling, the assembly feature data query output format from the database prototype is simulated. A...
Transportation Research Procedia, Dec 31, 2022
Tribology transactions, Jul 11, 2016
Proceedings of the Third International Conference on Railway Technology: Research, Development and Maintenance, Mar 10, 2016
The wheel-rail system operates in an open environment where the weather condition varies constant... more The wheel-rail system operates in an open environment where the weather condition varies constantly. In this laboratory study, an investigation using a pin-on-disc tribometer placed in a temperatur ...
Three railway brake block materials, i.e. cast iron, sintered and organic composite, were tested ... more Three railway brake block materials, i.e. cast iron, sintered and organic composite, were tested against railway wheel at10, 3, -10, -20 and -30 °C using a pin-on-disc tribometer with regards to th ...
Tribology International, Aug 1, 2021
Abstract This paper investigates the resistance of micropitting on two materials, using an FZG ba... more Abstract This paper investigates the resistance of micropitting on two materials, using an FZG back-to-back test rig with C-PT gears. The materials are wrought steel (16MnCr5) and a commercial powder metallurgical material (Astaloy™ Mo). Two finishing methods were studied: grinding and superfinishing. Experimental results show that the superfinishing prevented micropitting, but led to premature failure due to cracks in the root caused by tip-to-root interference. Micropitting was initiated at a higher load stage for the powder metallurgical steel compared to the ground wrought steel. The failure mechanisms were similar between materials with the same surface finish. The powder metallurgical steel showed subsurface initiated fatigue compared to the wrought ground steel having surface-initiated fatigue. Testing new finishing methods and materials, one has to be aware of the influence of the gear micro geometry.
Tribology Letters, Jul 20, 2012
Wear, Sep 1, 2015
ABSTRACT
Tribology International, Feb 1, 2018
The main objective of this study is to review the last decade of experimental work in the field o... more The main objective of this study is to review the last decade of experimental work in the field of gear pitting life andefficiency of an FZG gear test rig. Located at KTH Machine Design, the FZG ri ...
Study of surface roughness and surface orientation onfriction in rolling/sliding contacts : barre... more Study of surface roughness and surface orientation onfriction in rolling/sliding contacts : barrel-on-disc versustwin-disc
IQ-steel is isotropic (i.e. equally strong in all directions), cleaner, and with less inclusions ... more IQ-steel is isotropic (i.e. equally strong in all directions), cleaner, and with less inclusions than 16MnCr5 regular gear steel (RS). IQ-steel is used in diesel inlets and for bearings but to date ...
Lubrication science, Oct 1, 2008
Tribology Letters, May 28, 2020
Tribology transactions, Apr 15, 2019
Tribologia - Finnish Journal of Tribology
The ability to stop a gear fatigue test before catastrophic failure has many advantages. However,... more The ability to stop a gear fatigue test before catastrophic failure has many advantages. However, today, a widely accepted approach is not available. This case study applies a vibration-based condition monitoring methodology to detect early gear failures. The gear studied takes part in an all-wheel-drive drivetrain system. Vibration signals from four run-to-failure fatigue tests at two constant torque-speed combinations were used as input to time-synchronous averaging and autoregression model generation. The applied methodology shows promising results for early failure detection, and the process is feasible for implementation in an automated environment. Real time analysis is also possible since the autoregression model generates a healthy state TSA signal during the early testing stages. However, the time to failure detection varies with operating conditions, with low sensitivity at high-speed and low-torque conditions.
2017 International Conference on Mechanical, System and Control Engineering (ICMSC), 2017
This paper introduces the assembly feature data schema instance modeling to pre-examine the schem... more This paper introduces the assembly feature data schema instance modeling to pre-examine the schema functionality and output-as the preliminary step for data modeling. In order to link assembly with product design, it is essential to determine which entities of product design are involved at the automated assembly planning and operations. It is possible to assign meaningful attributes (assembly features) to the part model entities in a systematic and structured way. Using object-oriented design, the assembly feature data structure and its relationships are modeled. As a part of the research on product and assembly system data integration within the evolvable production system platform, the instance models for proposed assembly feature data structure provide a deeper understanding and error reduction that might possibly occur at the development of the database. Moreover through instance modeling, the assembly feature data query output format from the database prototype is simulated. A...