scholarly journals Ethoxylated Amine Friction Modifiers and ZDDP

2019 ◽  
Vol 67 (4) ◽  
Author(s):  
Joanna Dawczyk ◽  
Joe Russo ◽  
Hugh Spikes
Keyword(s):  
Harmful Effect ◽  
Lower Boundary ◽  
Rolling Contact ◽  
Boundary Friction ◽  
Friction Modifiers ◽  
Friction Modifier ◽  
Sliding Speed ◽  
Xanes Analysis ◽  
Selection Of

Abstract The influence of a series of Ethomeens (ethoxylated alkylamine organic friction modifiers) on the durability and friction of tribofilms formed by a commercial blend of primary and secondary ZDDP in sliding/rolling contact has been studied. When pre-formed ZDDP tribofilms are rubbed in Ethomeen solution, boundary friction is reduced and some of the ZDDP film is removed. Ethomeens having just two ethoxy groups give lower boundary friction on ZDDP than those with 15 ethoxy groups, but result in much greater removal of the tribofilm itself. Based on XANES analysis, the film removed by both types of Ethomeen consists primarily of nanocrystalline orthophosphate. The level of boundary friction and its dependence on sliding speed, coupled with the dimensions of the molecules, suggests that the Ethomeens with two ethoxy groups may form quite closely packed vertical monolayers on ZDDP tribofilm surfaces, but that those with fifteen ethoxy groups cannot be close packed; yet they still reduce boundary friction significantly. The study shows that selection of an appropriate aminic friction modifier for use with ZDDP is a balance between its ability to reduce friction and its potentially harmful effect on a ZDDP tribofilm.

Carry distance of top-of-rail friction modifiers

2018 ◽  
Vol 232 (10) ◽  
pp. 2418-2430
Author(s):  
Saad Ahmed Khan ◽  
Jan Lundberg ◽  
Christer Stenström
Keyword(s):  
Coefficient Of Friction ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Third Body ◽  
Friction Modifiers ◽  
Friction Modifier ◽  
Railway Traffic ◽  
Railway Industry ◽  
The Coefficient Of Friction

Rail issues such as corrugation, rolling contact fatigue, noise and wear have been increasing with the increase in railway traffic. The application of top-of-rail friction modifiers (TOR-FMs) is claimed by their manufacturers in the railway industry to be a well-established technique for resolving the above-mentioned issues. There are various methods for applying friction modifiers at the wheel–rail interface, among which stationary wayside systems are recommended by TOR-FM manufacturers when a distance of a few kilometres is to be covered. TOR-FM manufacturers also claim that by using wayside equipment, the TOR-FM can be spread over a minimum distance of 3 km, over which it maintains a coefficient of friction of µ = 0.35 ± 0.05. To determine the carry distance of TOR-FMs, some researchers use tribometers to measure the coefficients of friction. However, moisture and deposits from the environment and trains can alter the top-of-rail friction and give a misleading indication of the presence of a friction modifier. Therefore, the coefficient of friction itself is not a clear indicator of the presence of TOR-FMs. In the present study, cotton swabs dipped in a mixture of alcohol and ester were used to collect surface deposits (a third body) from both the wheel and rail at various distances from the point of application. Subsequently, the third body collected on the cotton swab was analysed using an energy dispersive X-ray analysis. The results have shown that the maximum carry distance of TOR-FMs on the top of the rail is limited to 70 m when using a TOR-FM from one manufacturer and to 450 m when using a TOR-FM from another manufacturer. The carry distance on the contact band of the wheel is limited to 100 m and 340 m. The friction modifier on the edges of the contact band was detected over a distance of up to 3 km; however, this will not minimise the damage or friction at the wheel–rail interface.

The Effect of Friction Modifiers on Wheel/Rail Isolation

2008 ◽  
Author(s):  
E. A. Gallardo Hernandez ◽  
J. Cotter ◽  
R. Lewis ◽  
D. T. Eadie
Keyword(s):  
Input Voltage ◽  
Electrical Circuit ◽  
Friction Modifiers ◽  
Friction Modifier ◽  
Contact Impedance ◽  
Static Tests ◽  
Railway Systems ◽  
Significant Difference ◽  
Track Circuit ◽  
The Impact

Train detection, for signalling purposes, is often by means of track circuits. Signalling block occupancy is triggered by the wheelset of the train ‘shorting out’ the track circuit, i.e. the wheels and axle act as a shunt. Contamination on the track such as ballast dust, rust, oil, or leaves as well as substances designed to improve train operation such as friction modifiers or sand may cause the contact between the wheelsets and the track to be compromised, inhibiting train identification. In previous work a twin disc approach has been used to study the effect of sand (used to improve adhesion) and leaves on wheel/rail isolation. Friction modifiers are of significant current interest in wheel/rail research. Introducing a new material into the tread/top of rail interface can raise questions about the impact on signalling systems. Although no significant effects have been observed in practical operation on a range of railway systems, the intention in this work was to evaluate conductance between wheel and rail in a more controlled and systematic fashion using the previously established methodology. Using the twin disc technique, friction modifier, in the form of a solid stick, was applied using a spring loaded device to the rotating wheel disc to generate a visible film. Tests were run to measure contact impedance at typical loads and slips. Static tests were also carried out using discs pre-conditioned with a friction modifier film. The electrical circuit used was a modified simplified simulation of audio frequency track circuit. No significant difference was observed in the measured impedance for dry conditions with no friction modifier, versus tests where friction modifier was applied, regardless of percentage slip or input voltage. The analysis suggests that the introduction of friction modifier into the existing wheel/rail interfacial film does not result in increased impedance with all other factors being equal.

scholarly journals Selection of Trichoderma spp. strains for the control of Sclerotinia sclerotiorum in soybean

2017 ◽  
Vol 52 (12) ◽  
pp. 1140-1148 ◽  
Author(s):  
Patrícia Elias Haddad ◽  
Luis Garrigós Leite ◽  
Cleusa Maria Mantovanello Lucon ◽  
Ricardo Harakava
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Culture Medium ◽  
Harmful Effect ◽  
Soybean Seeds ◽  
Trichoderma Spp ◽  
Negative Effect ◽  
Soybean Plants ◽  
Selection Of

Abstract: The objective of this work was to evaluate, in vitro and in vivo, the potential of Trichoderma spp. strains to control Sclerotinia sclerotiorum in soybeans (Glycine max) and to perform the molecular identification of the best perfoming strains. The effect of 120 strains of Trichoderma spp. on the viability of S. sclerotiorum sclerotia was evaluated in vitro through immersion in suspension of conidia from the antagonists and plating in culture medium. The best performing strains were evaluated in vivo, in a greenhouse, for control of the pathogen inoculated on 'Pintado' soybean seeds and plants. Of the 120 strains tested in vitro, 22 strains of Trichoderma spp. caused 100% inhibition of sclerotia germination. In the greenhouse, five strains inhibited the negative effect of the pathogen on seed germination and two strains increased in up to 67% plant dry matter. The best performing strains were identified as T. koningiopsis (3 strains), T. asperelloides (3), T. atroviride (2), and T. virens (1). Trichoderma strains are able to protect soybean plants from the harmful effect of S. sclerotiorum and, at the same time, they can promote the growth of the aerial part in greenhouse conditions.

scholarly journals A Novel Water-Shore-Line Detection Method for USV Autonomous Navigation

Sensors ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 1682 ◽  
Author(s):  
Xiong Zou ◽  
Changshi Xiao ◽  
Wenqiang Zhan ◽  
Chunhui Zhou ◽  
Supu Xiu ◽  
...  
Keyword(s):  
Line Segment ◽  
Autonomous Navigation ◽  
Field Experiments ◽  
Lower Boundary ◽  
Water Area ◽  
Epipolar Constraint ◽  
Shore Line ◽  
Inland River ◽  
Straight Line ◽  
Selection Of

For the navigation of an unmanned surface vehicle (USV), detection and recognition of the water-shore-line (WSL) is an important part of its intellectualization. Current research on this issue mainly focuses on the straight WSL obtained by straight line fitting. However, the WSL in the image acquired by boat-borne vision is not always in a straight line, especially in an inland river waterway. In this paper, a novel three-step approach for WSL detection is therefore proposed to solve this problem through the information of an image sequence. Firstly, the initial line segment pool is built by the line segment detector (LSD) algorithm. Then, the coarse-to-fine strategy is used to obtain the onshore line segment pool, including the rough selection of water area instability and the fine selection of the epipolar constraint between image frames, both of which are demonstrated in detail in the text. Finally, the complete shore area is generated by an onshore line segment pool of multi-frame images, and the lower boundary of the area is the desired WSL. In order to verify the accuracy and robustness of the proposed method, field experiments were carried out in the inland river scene. Compared with other detection algorithms based on image processing, the results demonstrate that this method is more adaptable, and can detect not only the straight WSL, but also the curved WSL.

scholarly journals New laboratory methodologies to analyse the top of rail friction modifier performance across different test scales

2020 ◽  
pp. 095440972091375
Author(s):  
M Harmon ◽  
R Lewis
Keyword(s):  
Test Methods ◽  
Relative Performance ◽  
Test Facility ◽  
Small Scale ◽  
Scaling Effects ◽  
Full Scale Test ◽  
Friction Modifiers ◽  
Friction Modifier ◽  
Test Standards ◽  
Scale Test

Test methodologies originally developed for greases have been adapted to be used for top of rail friction modifiers (TORFMs). This has included: a small-scale benchtop tribometer to measure the tackiness of different TORFMs, attaching an applicator bar to a section of rail and rolling a scaled-wheel through the TORFM applied to the rail head to analyse the effect of different variables on pick-up, and applying TORFM to a full-scale test facility to analyse the scaling effects and the effect of slip, load and speed on pick-up. These methods can be used to measure the relative performance of different TORFMs with respect to how much product is picked up by the wheel. The results have shown that the relative ranking of different TORFMs is the same across the three test scales. This shows that these small-scale test methods that are more suitable for inclusion in test standards could be used to reduce the need for the more time-consuming and expensive larger scale tests, as the relative performance is the same.

Computer-aided Shaft Design and Selection of Rolling-contact Bearings Using an Expert System

SIMULATION ◽  
2001 ◽  
Vol 76 (3) ◽  
pp. 151-159
Author(s):  
F. Mendi ◽  
A. Taskesen ◽  
Y. Kisioglu
Keyword(s):  
Expert System ◽  
Rolling Contact ◽  
Computer Aided ◽  
Selection Of

scholarly journals Prediction of the effects of friction control on top-of-rail cracks

2016 ◽  
Vol 232 (2) ◽  
pp. 484-494 ◽  
Author(s):  
Saad Ahmed Khan ◽  
Ingemar Persson ◽  
Jan Lundberg ◽  
Christer Stenström
Keyword(s):  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Reduction Factor ◽  
Rolling Contact ◽  
Friction Modifier ◽  
Index Model ◽  
Friction Control ◽  
The North ◽  
Train Speed ◽  
Multi Body

Rolling contact fatigue is a major problem connected with railway tracks, especially in curves, since it leads to higher maintenance costs. By optimising the top-of-rail friction, the wear and cracks on the top of the rail can eventually be reduced without causing very long braking distances. There are several research articles available on crack prediction, but most of the research is focused either on rail without a friction modifier or on wheels with and without friction control. In the present study, in order to predict the formation of surface-initiated rolling contact fatigue, a range of friction coefficients with different Kalker’s reduction factors has been assumed. Kalker’s reduction factor takes care of the basic tendency of creepage as a function of the traction forces at lower creepage. The assumed range covers possible friction values from those for non-lubricated rail to those for rail with a minimum measured friction control on the top of the rail using a friction modifier. A fatigue index model based on the shakedown theory was used to predict the generation of surface-initiated rolling contact fatigue. Simulations were performed using multi-body simulation, for which inputs were taken from the Iron Ore line in the north of Sweden. The effect of friction control was studied for different curve radii, ranging from 200 m to 3000 m, and for different axle loads from 30 to 40 tonnes at a constant train speed of 60 km/h. One example of a result is that a maximum friction coefficient (µ) of 0.2 with a Kalker’s reduction factor of 15% is needed in the case of trains with a heavy axle load to avoid crack formation.

Tribological characteristics at running‐in of repaired tractor engines using friction modifiers

2009 ◽  
Vol 61 (4) ◽  
pp. 209-212 ◽  
Author(s):  
Mitko I. Nikolov ◽  
Nina N. Gospodinova ◽  
Dimitar J. Pavlov ◽  
Mitko S. Dimitrov
Keyword(s):  
Design Methodology ◽  
Point Of View ◽  
Tribological Characteristics ◽  
Oil Composition ◽  
Friction Modifiers ◽  
Friction Couple ◽  
Friction Modifier ◽  
Content Type ◽  
Wear And Friction ◽  
Copper Oleate

PurposeThe purpose of this paper is to determine and compare the tribological characteristics (weight wear and friction moment) of a friction couple C45/C330 at running‐in with motor oil SAE 30 and different friction modifiers of copper oleate and zinc oleate.Design/methodology/approachFriction couples are tested using the model “roller‐sector” and they are lubricated with oil SAE 30 and two other samples of SAE 30 containing 0.6 per cent copper oleate and 0.6 per cent zinc oleate, respectively. Graphic dependencies are drawn for the weight wear of the sectors, rollers and couples; as well as for the running‐in moment, the friction moments at the end of the loading and at the end of the test.FindingsThe weight wear, running‐in moment and friction moments are evaluated for friction with SAE 30 as reference and oils containing copper oleate and zinc oleate as friction modifiers. The best performing material is the oil with zinc oleate.Originality/valueFrom a practical point of view this paper offers a new idea about a friction modifier – zinc oleate. Data for tribological characteristics and suitable concentration in the oil composition are given in the paper.

PROSPECTS FOR THE USE OF WORM GEARS IN VEHICLE DESIGNS

2020 ◽  
Vol 5 ◽  
pp. 67-72
Author(s):  
M.Yu. KARELINA ◽  
N.V. ATAMANENKO ◽  
Т.Yu. CHEREPNINA
Keyword(s):  
Comparative Analysis ◽  
Carbon Steels ◽  
Worm Gear ◽  
Cast Irons ◽  
Sliding Speed ◽  
Medium Carbon ◽  
Worm Wheel ◽  
Medium Carbon Steels ◽  
Worm Gears ◽  
Selection Of

The article analyzes the prospects for the use of worm gears in the construction of vehicles. A review of the method of calculating the worm gear has been carried out, approaches to the selection of materials for the worm itself and the worm wheel have been analyzed. A comparative analysis of the characteristics of improved and normalized medium-carbon steels and cast irons has been carried out. The characteristics of materials characterized by the best antifriction and anti-seize properties, in particular, tin bronzes, are given. The methods for predicting the reliability of a worm pair as well as methods for increasing the resource have been considered. The choice of the material of the worm gear depending on the sliding speed has been justified. Calculations have been given to prevent failures in the worm pair: chipping of the working surfaces of the teeth, kinking of the worm wheel tooth, seizing and wear, breakage of the worm's body, overheating, jamming of the gear and others.

Intermediate Distance Testing of Optical Top-of-Rail (TOR) Lubricity Sensors on a Remote-Controlled Rail Cart

2021 ◽  
Author(s):  
Timothy Mast ◽  
Yu Pan ◽  
Carvel Holton ◽  
Mehdi Ahmadian
Keyword(s):  
Optical Sensors ◽  
Field Tests ◽  
Qualitative Assessment ◽  
Measurement Unit ◽  
Friction Modifiers ◽  
Friction Modifier ◽  
High Speeds ◽  
Signal Characteristics ◽  
Class 1 ◽  
Intermediate Distance

Abstract The primary intent of this study is to evaluate the effectiveness and utility of a laser-based measurement unit for qualitative assessment of the presence and amount of Top-of-Rail Friction Modifier (TOR or TORFM), at reasonably high speeds and over long distances in the field. As a capstone to this phase of development, a series of field tests were conducted on revenue service track in partnership with a local Class 1 railroad. For these tests, the Third Generation Rail Lubricity Sensor was mounted on a Remote-Controlled Rail Cart and tested continuously over several miles of track. This longer window is able to cover the domain of multiple wayside applicators over a distance of more than 3 miles, the expected carry distance of TORFM. The results of this testing demonstrate the capacity of optical sensors to measure and evaluate track lubricity. The signal characteristics at or near wayside applicators demonstrate a clear impulse from the heavy lubricant close to the applicator. Further, by collecting continuous data down track from a wayside applicator it is possible to observe several novel ways in which the TORFM and flange grease carries beyond the point of application. One such example is a clear spike in track lubricity when entering or exiting curves caused by the lateral shift of the wheelsets drawing fresh lubricant previously out of contact with the rail into contact creating a “phantom applicator” effect. These observations are crucial to understanding in detail the way the TORFM and flange grease is carried down track. They are also essential to creating predictive models for most effective application of friction modifiers to specific track geometries.

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