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Lyu, Y., Bergseth, E., Wahlström, J. & Olofsson, U. (2019). A pin-on-disc study on the tribology of cast iron, sinter and composite railway brake blocks at low temperatures. Wear, 48-52
Öppna denna publikation i ny flik eller fönster >>A pin-on-disc study on the tribology of cast iron, sinter and composite railway brake blocks at low temperatures
2019 (Engelska)Ingår i: Wear, ISSN 0043-1648, E-ISSN 1873-2577, s. 48-52Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Most freight wagons in the EU use cast iron brake blocks. Cast iron brake blocks have a stable braking capability in different environmental conditions, but wear down the wheel tread quickly. Therefore, there is a need to understand the tribology of other brake block materials. A pin-on-disc tribometer placed in a temperature-controlled chamber is used to investigate the tribology of cast iron, sinter and composite railway brake blocks at low ambient temperatures. Pins made from different brake blocks are tested with discs made from steel wheels. Both friction coefficient and wear are evaluated at five different temperatures from + 10 to − 30 °C. The cast iron block demonstrated the greatest wear at − 10 and − 20 °C, due to the ductile-to-brittle transition at low temperatures. The worn graphite from cast iron is likely to become a solid lubricant, reducing the friction at − 10 and − 20 °C. For the composite brake block, a gradual decrease in friction with decreasing temperature was found. The sinter brake block was not sensitive to changes in ambient temperature. The sliding speed in the current study is relatively low and further study at higher speed is suggested in order to evaluate the tribological performance of different brake blocks.

Ort, förlag, år, upplaga, sidor
Elsevier, 2019
Nyckelord
Brake blocks, Composite, Pin-on-disc, Railway, Temperature, Tribology
Nationell ämneskategori
Tribologi (ytteknik omfattande friktion, nötning och smörjning)
Identifikatorer
urn:nbn:se:kth:diva-246451 (URN)10.1016/j.wear.2019.01.110 (DOI)000464582200006 ()2-s2.0-85061381732 (Scopus ID)
Anmärkning

QC 20190320

Tillgänglig från: 2019-03-20 Skapad: 2019-03-20 Senast uppdaterad: 2019-05-14Bibliografiskt granskad
Bergseth, E., Höjer, M., Lyu, Y., Nilsson, R. & Olofsson, U. (2019). A Wear Detection Parameter for the Wheel–Rail Contact Based on Emitted Noise. Tribology Transactions, 62(3), 496-503
Öppna denna publikation i ny flik eller fönster >>A Wear Detection Parameter for the Wheel–Rail Contact Based on Emitted Noise
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2019 (Engelska)Ingår i: Tribology Transactions, ISSN 1040-2004, E-ISSN 1547-397X, Vol. 62, nr 3, s. 496-503Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

This article describes how a wheel–rail wear detection parameter based on noise was developed by running a rapid transit train instrumented with microphones in a depot with a small curve radius. This full-scale test made use of previous knowledge gained from lab-scale tests. The lab- and full-scale tests showed that noise could be used as an indicator of wear transition, when normal wear turns into severe or catastrophic wear. This transition was accompanied by a significant increase in sound pressure and a broader sound pressure amplitude spectrum; that is, a narrow initial amplitude distribution in the normal wear regime and a broader distribution in the severe wear regime. The measured noise from the inner/low and outer/high rails was analyzed in conjunction with the wear from the outer wheel and comparisons were made between cleaned (exposed to severe wear) and lubricated (no wear) rail. Based on those analyses, a wear detection parameter criterion was developed for this specific train. This wear parameter has been implemented in a real-time condition monitoring system so that warnings of the risk for severe wear could be sent to the maintenance department. Validation of the wear parameter and challenges linked to open system conditions are discussed in this article.

Nyckelord
Railway, noise, condition monitoring, wear, wheel–rail contact
Nationell ämneskategori
Tribologi (ytteknik omfattande friktion, nötning och smörjning) Farkostteknik
Forskningsämne
Järnvägsgruppen - Tribologi; Maskinkonstruktion
Identifikatorer
urn:nbn:se:kth:diva-249942 (URN)10.1080/10402004.2019.1576957 (DOI)000466145500001 ()2-s2.0-85064477098 (Scopus ID)
Forskningsfinansiär
EU, FP7, Sjunde ramprogrammet
Anmärkning

QC 20190522

Tillgänglig från: 2019-04-23 Skapad: 2019-04-23 Senast uppdaterad: 2019-05-22Bibliografiskt granskad
Bergseth, E., Henriksson, M., Dizdar, S. & Sellgren, U. (2019). Effects of thrust washer bearing surface characteristics on planetary gear train wear. Wear, 432-433, Article ID 202933.
Öppna denna publikation i ny flik eller fönster >>Effects of thrust washer bearing surface characteristics on planetary gear train wear
2019 (Engelska)Ingår i: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 432-433, artikel-id 202933Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Thrust washers in spur planetary gears are placed between the planet wheel and planet carrier and act as spacers and wear pads. Metal to metal sliding contact between the planet wheel – washer – carrier causes frictional power losses that, combined with starved lubrication, may cause high contact temperatures and thermo-mechanical effects that potentially trigger thermo-elastic instabilities and excessive local wear. The planetary gear system would benefit from a low-friction interface between the washer and the planet wheel. Five washers with different surface treatments were tested in a full-scale gear rig. These tests were also replicated as closely as possible in a pin-on-disc tribometer. The following types of finishing material treatments were studied: a chemical nickel coating plus polymer on a nitro-carburised surface, a combination of nitro-carburization and solid lubricant layers, electroless deposited chemical nickel coating plus polymer, nitro-carburizing, and manganese phosphating. The frictional results indicate that tribometer tests can be used to compare and classify new washer materials. Lab scale tests show that a new experimental self-lubricating tribomaterial that was applied with laser cladding has a promising potential to increase planetary gear train robustness and service life, especially if the surface is fine grinded.

Ort, förlag, år, upplaga, sidor
Elsevier, 2019
Nyckelord
Thrust washers, Planetary gears, Adhesive wear, Surface treatment, Laser cladding
Nationell ämneskategori
Tribologi (ytteknik omfattande friktion, nötning och smörjning)
Forskningsämne
Transportvetenskap; Maskinkonstruktion
Identifikatorer
urn:nbn:se:kth:diva-258028 (URN)10.1016/j.wear.2019.202933 (DOI)000477874700023 ()2-s2.0-85067419223 (Scopus ID)
Forskningsfinansiär
Stiftelsen för strategisk forskning (SSF), SM15-0025
Anmärkning

QC 20191007

Tillgänglig från: 2019-09-09 Skapad: 2019-09-09 Senast uppdaterad: 2019-10-11Bibliografiskt granskad
Bergseth, E., Sosa, M., Andersson, M. & Olofsson, U. (2018). A note on the pitting life of IQ steel versus 16MnCr5 steel in a back to back gear test rig. In: : . Paper presented at 18th Nordic Symposium on Tribology (NORDTRIB 2018) in Uppsala on 18 - 21 June 2018.
Öppna denna publikation i ny flik eller fönster >>A note on the pitting life of IQ steel versus 16MnCr5 steel in a back to back gear test rig
2018 (Engelska)Konferensbidrag, Poster (med eller utan abstract) (Refereegranskat)
Abstract [en]

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 has not been used for gears. Previous studies, has shown good potential to increase the bending fatigue life of gears. The method in this study is a mechanical test procedure to determine the pitting load capacity of gear transmission lubricants, but with the focus on comparing the pitting load capacity of the two steel types IQ-steel with RS. Times to failures, photographs of the fatigue damage are presented in the study. Gear teeth from each steel type were analysed using SEM. The results, which are based on six tests in total (three IQ-steel and three RS-steel gear pairs), indicate that the IQ-steel may have at least similar surface capacity as the regular steel.

Keywords: Pitting life, Gear, IQ-steel

Nationell ämneskategori
Metallurgi och metalliska material
Identifikatorer
urn:nbn:se:kth:diva-249939 (URN)
Konferens
18th Nordic Symposium on Tribology (NORDTRIB 2018) in Uppsala on 18 - 21 June 2018
Anmärkning

QC 20190522

Tillgänglig från: 2019-04-23 Skapad: 2019-04-23 Senast uppdaterad: 2019-05-22Bibliografiskt granskad
Bergseth, E., Olofsson, U., Andersson, M. & Sosa, M. (2018). EXPERIENCES OF STUDYING GEAR TRIBOLOGY IN A FZG TEST SET-UP. In: : . Paper presented at The 18th Nordic Symposium on Tribology – NORDTRIB 2018 18-21 June 2018, Uppsala University, Uppsala, Sweden.
Öppna denna publikation i ny flik eller fönster >>EXPERIENCES OF STUDYING GEAR TRIBOLOGY IN A FZG TEST SET-UP
2018 (Engelska)Konferensbidrag, Muntlig presentation med publicerat abstract (Refereegranskat)
Abstract [en]

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 rig has led to critical findings with an impacton gear transmissions, such as high efficiency and long fatigue life. The different FZG test set-ups, the sampling methodsand the results (and their limitations) are discussed, and measures are proposed to reduce the limitations. The findingsof this study are used as input to an impact case on how research at a university can provide the major transportindustry in Sweden with the knowledge and the methods to evaluate gear performance.

Nyckelord
FZG; Gear rig; Efficiency; Pitting life; Impact.
Nationell ämneskategori
Tribologi (ytteknik omfattande friktion, nötning och smörjning)
Forskningsämne
Maskinkonstruktion
Identifikatorer
urn:nbn:se:kth:diva-249941 (URN)
Konferens
The 18th Nordic Symposium on Tribology – NORDTRIB 2018 18-21 June 2018, Uppsala University, Uppsala, Sweden
Anmärkning

QC 20194030

Tillgänglig från: 2019-04-23 Skapad: 2019-04-23 Senast uppdaterad: 2019-04-30Bibliografiskt granskad
Lyu, Y., Bergseth, E. & Olofsson, U. (2018). TRIBOLOGY OF THREE RAILWAY BRAKE BLOCK MATERIALS TESTED AGAINST RAILWAYWHEEL AT LOW TEMPERATURES. In: : . Paper presented at The 18th Nordic Symposium on Tribology – NORDTRIB 201818-21 June 2018, Uppsala University, Uppsala, Sweden.
Öppna denna publikation i ny flik eller fönster >>TRIBOLOGY OF THREE RAILWAY BRAKE BLOCK MATERIALS TESTED AGAINST RAILWAYWHEEL AT LOW TEMPERATURES
2018 (Engelska)Konferensbidrag, Muntlig presentation med publicerat abstract (Refereegranskat)
Abstract [en]

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 the friction and wear performance. At -10 and -20 °C, cast iron tests yielded very high wear losses both on pin and disc samples and low friction coefficient. The largeamount of graphite worn off from the cast iron sample acted as a lubricant. Friction and wear of sintered material arenot sensitive to the change of temperature. Disc sample tested against organic composite at -30 °C showed negativewear loss, indicating that materials were added onto the surface.

Nyckelord
Brake block; Pin-on-disc; Friction; Wear.
Nationell ämneskategori
Tribologi (ytteknik omfattande friktion, nötning och smörjning)
Forskningsämne
Maskinkonstruktion
Identifikatorer
urn:nbn:se:kth:diva-249962 (URN)
Konferens
The 18th Nordic Symposium on Tribology – NORDTRIB 201818-21 June 2018, Uppsala University, Uppsala, Sweden
Anmärkning

QC 20190522

Tillgänglig från: 2019-04-24 Skapad: 2019-04-24 Senast uppdaterad: 2019-05-22Bibliografiskt granskad
Mahmood Reza, K., Wikander, J., Bergseth, E., Maffei, A. & Onori, M. (2017). Assembly Feature Data Instance Modeling: Prototype Implementation and Outputs. In: 2017 INTERNATIONAL CONFERENCE ON MECHANICAL, SYSTEM AND CONTROL ENGINEERING (ICMSC): . Paper presented at International Conference on Mechanical, System and Control Engineering (ICMSC), MAY 19-21, 2017, St Petersburg, RUSSIA (pp. 343-347). IEEE
Öppna denna publikation i ny flik eller fönster >>Assembly Feature Data Instance Modeling: Prototype Implementation and Outputs
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2017 (Engelska)Ingår i: 2017 INTERNATIONAL CONFERENCE ON MECHANICAL, SYSTEM AND CONTROL ENGINEERING (ICMSC), IEEE , 2017, s. 343-347Konferensbidrag (Refereegranskat)
Abstract [en]

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. An industrial assembly model example with its 3DPart models is chosen to demonstrate the realized assembly feature data set with string data type. The models support the desired simplicity at the database prototype implementation. The output format envisions the interoperability factor between product models and the assembly planning systems.

Ort, förlag, år, upplaga, sidor
IEEE, 2017
Nyckelord
assembly automation, assembly modeling, assembly feature, instance modeling, unified modeling language
Nationell ämneskategori
Maskinteknik
Identifikatorer
urn:nbn:se:kth:diva-211425 (URN)10.1109/ICMSC.2017.7959498 (DOI)000405221400068 ()2-s2.0-85025826079 (Scopus ID)978-1-5090-6530-1 (ISBN)
Konferens
International Conference on Mechanical, System and Control Engineering (ICMSC), MAY 19-21, 2017, St Petersburg, RUSSIA
Anmärkning

QC 20170802

Tillgänglig från: 2017-08-02 Skapad: 2017-08-02 Senast uppdaterad: 2020-03-05Bibliografiskt granskad
Bergseth, E., Henriksson, M., Broukhiyan, P., Sugutur, L., Sellgren, U. & Nordin, E. (2017). EFFECTS OF THRUST WASHER BEARING SURFACE CHARACTERISTICS ON PLANETARY GEAR TRAIN WEAR. In: : . Paper presented at 44th Leeds-Lyon Symposium on Tribology - September 4-6, 2017, Lyon, France.
Öppna denna publikation i ny flik eller fönster >>EFFECTS OF THRUST WASHER BEARING SURFACE CHARACTERISTICS ON PLANETARY GEAR TRAIN WEAR
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2017 (Engelska)Konferensbidrag, Muntlig presentation med publicerat abstract (Refereegranskat)
Nyckelord
Thrust Washers; Planetary Gears; Wear
Nationell ämneskategori
Tribologi (ytteknik omfattande friktion, nötning och smörjning)
Identifikatorer
urn:nbn:se:kth:diva-249948 (URN)
Konferens
44th Leeds-Lyon Symposium on Tribology - September 4-6, 2017, Lyon, France
Anmärkning

QC 20190522

Tillgänglig från: 2019-04-23 Skapad: 2019-04-23 Senast uppdaterad: 2019-05-22Bibliografiskt granskad
Li, X., Olofsson, U. & Bergseth, E. (2017). Pin-on-Disc Study of Tribological Performance of Standard and Sintered Gear Materials Treated with Triboconditioning Process: Pre-treatment by Pressure-induced Tribo-film formation. Tribology Transactions, 60(1), 47-57
Öppna denna publikation i ny flik eller fönster >>Pin-on-Disc Study of Tribological Performance of Standard and Sintered Gear Materials Treated with Triboconditioning Process: Pre-treatment by Pressure-induced Tribo-film formation
2017 (Engelska)Ingår i: Tribology Transactions, ISSN 1040-2004, E-ISSN 1547-397X, Vol. 60, nr 1, s. 47-57Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

oating is one of the innovative approaches used to improve the wear resistance and load-carrying capacity of surfaces in rolling-sliding contact, such as gears and rolling element bearings. In this study, the tribological performance of standard gear material (16MnCr5) and two kinds of powder metallurgy (PM) gear material (Distaloy AQ + 0.2% C and Astoloy 85Mo +0.2% C) with and without tribofilms formed by a pre-treatment were evaluated. Specimens treated with the pre-treatment and the substrate is subjected to pin-on-disc tests under boundary lubrication conditions. The friction and wear performance of the two different PM gear materials with the pre-treatment formed tribo-film were compared to RS-RS (16MnCr5 material disc and pin combination) for reference. It was found that the pre-treatment lowers the friction coefficient and enhances the wear resistance of pins because of the tribo-film formed. The tribo-film caused good running-in due to the existing of  and Fe and W oxides. Mo-Mo (Astoloy 85Mo + 0.2% C material disc and pin combination) and Mo-RS (Astoloy 85Mo + 0.2% C disc and 16MnCr5 pin combination) showed statistically significant higher wear resistance.

Ort, förlag, år, upplaga, sidor
Taylor & Francis Group, 2017
Nyckelord
Gear material, Powder metallurgy, Pre-treatment, Wear, Friction
Nationell ämneskategori
Tribologi (ytteknik omfattande friktion, nötning och smörjning)
Forskningsämne
Industriell ekonomi och organisation
Identifikatorer
urn:nbn:se:kth:diva-187443 (URN)10.1080/10402004.2016.1146379 (DOI)000392598200006 ()2-s2.0-84978062920 (Scopus ID)
Anmärkning

QC 20160523

Tillgänglig från: 2016-05-23 Skapad: 2016-05-23 Senast uppdaterad: 2019-01-30Bibliografiskt granskad
Bergseth, E., Söderberg, A., Zhu, Y. & Olofsson, U. (2017). Study of surface roughness and surface orientation on friction in rolling/sliding contacts: barrel-on-disc versus twin-disc. In: : . Paper presented at Sixth World Tribology Congress (WTC 2017), Beijing, China, September 17-22, 2017.
Öppna denna publikation i ny flik eller fönster >>Study of surface roughness and surface orientation on friction in rolling/sliding contacts: barrel-on-disc versus twin-disc
2017 (Engelska)Konferensbidrag, Muntlig presentation med publicerat abstract (Refereegranskat)
Abstract [en]

Gears are one of the most important means of mechanical power transmission. Even though the efficiency is high for a gear pair today, further decrease in friction can contribute to lower the fuel consumption. A barrel-on-disc machine (same setup as ball-on-disc) to simulate a rolling/sliding gear contact was used to study the impact of manufacturing method, grinding and superfinishing, on friction. To evaluate the extent to which friction and wear can be diminished by reducing surface roughness and changing surface orientation. Measurement results showed that the change of lubricant had an impact on friction in the mixed to boundary lubrication regimes similar to that of the change of main surface orientation. The results were compared with those from a parallel study involving a twin-disc machine, also used to simulate rolling/sliding contacts (see Figure). Measurements and simulations showed that the barrel-on-disc and twin-disc setups reflected the same friction trends. However, the friction coefficient using the barrel-on-disc setup was almost twice as large as that found using the twin-disc machine. The wear mechanisms also differed: micropits occurred on discs used in the twin-disc set-up whereas normal or no wear was found on the barrel-on-disc specimens. The difference in contact geometry is believed to be the main reason for the higher friction level in the barrel-on-disc machine. A computer contact analysis was used to clarify the differences using perfectly smooth and computer-generated textured surfaces.

Nyckelord
Surface finish; Tribotest; Contact analysis
Nationell ämneskategori
Tribologi (ytteknik omfattande friktion, nötning och smörjning)
Identifikatorer
urn:nbn:se:kth:diva-249944 (URN)
Konferens
Sixth World Tribology Congress (WTC 2017), Beijing, China, September 17-22, 2017
Anmärkning

QC 20190522

Tillgänglig från: 2019-04-23 Skapad: 2019-04-23 Senast uppdaterad: 2019-05-22Bibliografiskt granskad
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0003-4447-3363

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