Pattern Abrasion and Other Mechanisms of Wear of Tank Track Pads

1992 ◽  
Vol 65 (1) ◽  
pp. 154-175 ◽  
Author(s):  
A. I. Medalia ◽  
A. L. Alesi ◽  
J. L. Mead
Keyword(s):  
Wear Rate ◽  
Surface Pattern ◽  
The Road ◽  
Test Conditions ◽  
Ridge Height ◽  
Standard Compound ◽  
Mode Of Failure ◽  
Cross Country ◽  
Eventual Loss ◽  
Paved Road

Abstract Wear of tank track pads has been studied under different conditions. With T142 pads tested on an M-60 tank, the mode of failure was found to depend on the test conditions. Among eighteen experimental compounds tested, improved wear (vs. the standard compound) under one test condition was generally at the expense of poorer wear under one or both of the other test conditions. However, in agreement with previous results, an HNBR/Zn-methacrylate/peroxide compound gave improved wear rate under all three test conditions. Wear of the T142 pads on a hilly cross-country course and on a combination course was generally by massive chunking. On a paved road course, most compounds wore by pattern abrasion. A few compounds worn on this course formed deep pockets parallel to the surface, resulting in the eventual loss of the large flaps between the pocket and the surface. Pattern abrasion was also found on T156 pads of four different compounds, tested on an M-1 tank on the paved road course. The abrasion patterns of both types of pads had a shingled appearance, with the ridges pitched so as to bite into the road surface. The abrasion patterns were characterized quantitatively by profilometry, using standard parameters calculated for surface roughness of metals and other materials. The ridge height and its ratio to ridge spacing correlated positively with wear rate on the paved road; whereas there was no correlation of ridge spacing with wear rate. The compounds which gave the lowest wear rate on the paved road, including the HNBR compounds, gave shallow ridges with little or no pattern.

Vibration Measurement and Spectral Analysis of Chassis Frame Mounted Structure for Off-Road Wheeled Heavy Vehicles

2016 ◽  
Vol 8 (1) ◽  
Author(s):  
V.R. Deulgaonkar
Keyword(s):  
Spectral Analysis ◽  
Spectral Density ◽  
Power Spectral Density ◽  
Dominant Frequency ◽  
Vibration Measurement ◽  
Road Transportation ◽  
The Road ◽  
Power Spectral ◽  
Cross Country ◽  
Paved Road

Chassis mounted structure is a base component for shelters or containers mounted on heavy transport vehicles. When the vehicle is driven in rough terrains or during off-road transportation this structure has a significant role in protecting the sophisticated cargo and intelligent tracking systems placed inside the shelters. During off-road transportation or warhead conditions the vehicle is subjected to large unevenness in load due to road or soil irregularities in rough terrains, which causes vibrations to be induced in the vehicle. As the nature of vibrations induced in vehicle during travel on off-road or cross-country terrains is random and unpredictable, there is a concern to analyse the vibration response of chassis and chassis mounted structures is needed. Present work deals with vibration measurement and spectral analysis of a chassis mounted structure designed for off-road and commercial transport vehicles. The road profile on which the vibration measurement has been carried out includes paved road and cross-country terrain segments. The vibration measurement has been carried at three different vehicle speeds. Signal analysis procedure for the acquired test data is discussed. The chassis mounted structure under concern is intended to hold two shelters or containers. From the vibration measurement at critical locations, g-(RMS) and g-(peak) values for paved and cross-country roads have been found out. Power spectral density values have also been found on chassis and structure for the same transport situations. Major inferences include the evaluation of minimum and maximum g-values (peak and RMS) on chassis and chassis mounted structure. Power spectral density graphs are constructed from which the dominant frequency for both road profiles is found out.

scholarly journals Influence of Test Conditions on Sliding Wear Performance of High Velocity Air Fuel-Sprayed WC–CoCr Coatings

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3074
Author(s):  
Kaveh Torkashvand ◽  
Vinod Krishna Selpol ◽  
Mohit Gupta ◽  
Shrikant Joshi
Keyword(s):  
Wear Rate ◽  
Test Performance ◽  
Sliding Wear ◽  
Normal Load ◽  
Specific Wear Rate ◽  
Wear Behaviour ◽  
Wear Performance ◽  
Test Conditions ◽  
Test Parameters ◽  
Sliding Distance

Sliding wear performance of thermal spray WC-based coatings has been widely studied. However, there is no systematic investigation on the influence of test conditions on wear behaviour of these coatings. In order to have a good understanding of the effect of test parameters on sliding wear test performance of HVAF-sprayed WC–CoCr coatings, ball-on-disc tests were conducted under varying test conditions, including different angular velocities, loads and sliding distances. Under normal load of 20 N and sliding distance of 5 km (used as ‘reference’ conditions), it was shown that, despite changes in angular velocity (from 1333 rpm up to 2400 rpm), specific wear rate values experienced no major variation. No major change was observed in specific wear rate values even upon increasing the load from 20 N to 40 N and sliding distance from 5 km to 10 km, and no significant change was noted in the prevailing wear mechanism, either. Results suggest that no dramatic changes in applicable wear regime occur over the window of test parameters investigated. Consequently, the findings of this study inspire confidence in utilizing test conditions within the above range to rank different WC-based coatings.

EXTERNAL PARTICLE SHAPE ANALYSIS AND ITS EFFECT ON TRIBOLOGICAL PERFORMANCE OF DISC BRAKE

2016 ◽  
Vol 78 (9) ◽  
Author(s):  
Ahmad Fawwaz Abdul Aziz ◽  
Mohd Kameil Abdul Hamid
Keyword(s):  
Friction Coefficient ◽  
Wear Rate ◽  
Particle Shape ◽  
Silica Sand ◽  
Variable Load ◽  
Shape Effect ◽  
Disc Brake ◽  
External Particle ◽  
The Road ◽  
Open Design

The open design of disc brake and its location close to the road surface may lead the road particles of various sizes and shapes to enter in between brake pads and disc rotor. This study presents an experimental approach to determine the particle shape effect on friction and wear characteristics of OEM disc brake under different operating condition. Two types of external particles which are road particles and silica sand with two range of size of 200 µm and 400 µm were used. Testing was conducted for variable load and sliding speed. Presence of external particle with various size and shape affect the wear rate, friction coefficient and surface topography of the brake pad. Smaller particle generated more wear. Moreover, the particles which have sharped shape or high angularity resulted in higher weight loss of the pad and contribute to greater formation of compacted wear debris. Wear rate and friction coefficient also increase with contact pressure.   

A new Republican temple on the via Appia, at the borders of Rome's urban space

2016 ◽  
Vol 29 ◽  
pp. 327-347
Author(s):  
Rachele Dubbini
Keyword(s):  
Urban Space ◽  
Sewer System ◽  
The Road ◽  
Republican Era ◽  
History Of ◽  
Paved Road

On May 27, 1970, during construction of the Caffarella sewer system which was to serve new districts in the sprawling suburbs of Rome, the Municipality of Rome alerted the Soprintendenza to the discovery of some ancient structures near the via Appia.The area affected by the passage of the sewer system lies just beyond the Almo river, between the Appia's first and second mile, in a place where, at the end of the 19th c., P. Cartoni built a rather large barn for his estate (vigna). On the W side of the road, excavators discovered a concrete pedestal reveted with tuff blocks that was interpreted as the foundation of a sepulchral monument, the ruderatio of the via Appia, and a secondary paved road leading southeast, as published by L. Spera (see fig. 1, trench A). However, the excavations on the E side of the via Appia have never been published. The aim of this paper is to describe and interpret the remarkable discovery. My examination of documentation stored in the archives of the Soprintendenza identified photographs and sketches of the 1970 excavation, providing evidence for the existence of a Republican-era monumental architectural complex situated behind the barn of Vigna Cartoni. Since it was impossible unfortunately to locate any written reports, the research was based mostly on illustrations and administrative documents, but a fairly accurate history of the excavation could be reconstructed based on the latter.

scholarly journals Emergence of a new salt-tolerant alien grass along roadsides? Occurrence of Diplachne fusca subsp. fascicularis (Poaceae) in Hungary

2021 ◽  
Vol 80 (2) ◽  
Author(s):  
Kristóf Süveges ◽  
Attila V. Molnár ◽  
Attila Mesterházy ◽  
Júlia Tüdősné Budai ◽  
Réka Fekete
Keyword(s):  
Salt Content ◽  
Rice Paddy ◽  
Salt Tolerant ◽  
The Road ◽  
Reproduction Strategy ◽  
Temporal And Spatial Variability ◽  
Nacl Concentration ◽  
Negative Effect ◽  
Hungarian Population ◽  
Paved Road

This paper reports the occurrence of a North American salt-tolerant taxon, Diplachne fusca subsp. fascicularis (Lam.) P.M.Peterson et N.Snow in Hungary (Central-Europe). Two earlier Hungarian observations of D. fusca were known from 1915, near Győr (West Transdanubia), later the taxon was collected by Pénzes in 1958, in downtown Budatétény (central Hungary. Both observations seem to be occasional. Recently, the taxon has started spreading in Europe, mainly on rice paddy fields, with a serious invasion potential. In North America its appearance on ruderal habitats, as well as along roads and other linear infrastructures is a well known phenomenon. The Hungarian population was found near Cegléd (Central Hungary) on the roadside of the E40 primary main road in September 2018. In July 2019 more than one thousand (mostly vegetative) individuals were detected. The salt content of the habitat shows remarkable temporal and spatial variability. At one meter distance from the edge of the paved road soil salt content was higher in spring (after the winter de-icing regime), than in autumn. Salt concentration was highest in the vicinity of the road, and decreased with increasing distance from it. Germination tests revealed a significant negative effect of NaCl concentration on germination rates, but germination occurred even on extremely saline substrates with 1.5% NaCl concentration. Considering its biology and reproduction strategy, the further spread of Diplachne fusca is highly presumable.

scholarly journals ANALISIS TINGKAT KEAUSAN TERHADAP PEMAKAIAN BAN MEREK A, B DAN C MENGGUNAKAN BAN STANDAR 90/90-14 46 P

2021 ◽  
Vol 8 (1) ◽  
pp. 282-288
Author(s):  
Afdan Ufriandi
Keyword(s):  
Wear Rate ◽  
Direct Contact ◽  
Road Surface ◽  
Total Load ◽  
The Road ◽  
Selection Of

The tire is the part of the motorbike that is in direct contact with the road surface. Selection of the correct tires, greatly determines the safety of riders from the dangers of slides on certain roads. In this research, the author aims to determine the wear rate of standard tires for Products A, B and C 90 / 90-14 M / C 46P when traveling, to prevent damage or wear of tires. In the comparison of Speeds 3,000 rpm, 3500 rpm and 4000 rpm with total load 223 Kg, 233 Kg and 243 Kg, with 1 hour in 3 times of testing. The erosion that occurs in the new tire A is 192 grams with 8.14% erosion and 7588 km / hour in tire mileage. Meanwhile, the new B tires are 182 grams, 5.71% scraping and 10,568 km / hr of the tire mileage. While the new C tire is 188 grams, 5.54% erosion and 11384 km / hour tire mileage.

Evaluation of the Long-Term Performance of Woven Geotextile Used between Base Course and Subgrade of a Paved Road

2019 ◽  
Vol 2673 (8) ◽  
pp. 310-321 ◽  
Author(s):  
Saad Ullah ◽  
Burak F. Tanyu ◽  
Erol F. Guler ◽  
Edward J. Hoppe ◽  
Emre Akmaz
Keyword(s):  
Transportation Network ◽  
Experimental Program ◽  
The Road ◽  
Low Volume Roads ◽  
Road Profile ◽  
Low Volume ◽  
Base Course ◽  
Virginia Department ◽  
Paved Road ◽  
Term Performance

The purpose of this research was to investigate the properties of the exhumed geotextile from a low-volume road on the Virginia Department of Transportation network. The exhumed geotextiles have been in service for 23 years, which provided an opportunity to evaluate the longevity of the materials as well as to make assessments of how it relates to the changes in material properties. During this investigation, subgrade and base course materials were also obtained from the same site and an experimental program was developed to evaluate the effectiveness of the exhumed geotextiles for separation, stabilization, and filtration for the base course thicknesses of 4, 6, and 8 in. The results from this study combined with the results from the previous studies conducted at the same site showed that when the geotextile is placed between the subgrade and base course, the thinner the pavement section, the more evident the effectiveness of the geotextile improvements. One important finding of this research was that the placement of a geotextile reduced the particle breakage caused by abrasion under the applied transient loads. This was observed as a stabilization effect of the geotextile inclusion. As a general conclusion, for low-volume roads with relatively thin pavement sections, properly selected geotextiles provide benefits for separating the subgrade and base course (minimizing pumping), filtering infiltrated or ground water, and stabilizing the road profile. These benefits become more apparent when the thickness of the base course is less than 8 in.

scholarly journals Effect of paved road density on abundance of white-tailed deer

2012 ◽  
Vol 39 (6) ◽  
pp. 478 ◽  
Author(s):  
Keith G. Munro ◽  
Jeff Bowman ◽  
Lenore Fahrig
Keyword(s):  
Positive Relationship ◽  
Habitat Availability ◽  
Road Mortality ◽  
Road Density ◽  
The Road ◽  
Populations At Risk ◽  
Density Values ◽  
Conservation Concern ◽  
Paved Road ◽  
Perceived Predation Risk

Context Although ~3% of white-tailed deer are killed on roads each year, no previous study has tested for an effect of roads on deer abundance. This is difficult to do because road density is generally negatively correlated with deer habitat availability. Aims Our goal was to determine whether roads affect deer abundance. Methods First, we used an existing dataset from Pennsylvania, USA, to determine a range of paved road densities representing a significant range in deer per capita mortality. We then conducted a field study in eastern Ontario, Canada, with sample sites for relative deer abundance selected such that (1) road density in the surrounding landscapes varied over this same range, and (2) there were low correlations across landscapes between road density and deer habitat availability. The latter allowed us to isolate the effects of roads from the effects of habitat on deer abundance. We indexed relative deer abundance using a combination of pellet samples and track counts. Key results Unexpectedly, we observed a positive relationship between relative deer abundance and paved road density. Conclusions We speculate that this positive relationship is due to (1) reduced deer predation and/or perceived predation risk and/or hunting pressure in landscapes with higher road density and/or (2) provision of a resource or service by roads, the benefits of which outweigh the road mortality. Implications We found no evidence that road mortality places deer populations at risk of decline, at least over the range of road density values in our study. Therefore we conclude that road mortality is not a conservation concern for white-tailed deer in ecological contexts similar to our study areas.

scholarly journals Investigations on the Wear Rate of Sintering Diamond Core Bit during the Hole Drilling Process of Al2O3 Bulletproof Ceramics

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Lei Zheng ◽  
Chen Zhang ◽  
Xianglong Dong ◽  
Shitian Zhao ◽  
Weidong Wu ◽  
...  
Keyword(s):  
Wear Rate ◽  
Spindle Speed ◽  
Machining Process ◽  
Hole Drilling ◽  
Drilling Process ◽  
Thin Wall ◽  
Diamond Grit ◽  
Machining Quality ◽  
Test Conditions ◽  
Finer Diamond

Bulletproof ceramics are usually hard and brittle with high elastic modulus, high compressive strength, and low tensile strength. While machining bulletproof ceramics, severe tool wear makes it difficult to obtain desired machining quality and efficiency, especially in hole drilling. In this work, an intensive experimental study on the overall wear rate of the sintering diamond thin-wall core bit during the hole drilling of Al2O3 bulletproof ceramics (99 wt.%) has been carried out. The quality loss of the bit after each hole drilled was selected for representing the overall wear rate of the bit. Based on experimental data, the influences of the main bit performance and machining process parameters on the overall wear rate of the bit have been analyzed. According to the results discussed, under the test conditions, finer diamond grit, higher diamond concentration, lower number of water gaps, thinner wall thickness, or lower bit load all can decrease the wear rate of the bit. However, within a certain range, the spindle speed has little influence on the overall wear resistance of the bit, but when the spindle speed increases, the machining efficiency can be significantly improved. The results obtained in this work can offer a valuable reference for the use of sintering diamond thin-wall core bits in the hole drilling of bulletproof ceramics.

Friction on Wet Surfaces of Tire-Tread-Type Vulcanizates

1964 ◽  
Vol 37 (4) ◽  
pp. 878-893 ◽  
Author(s):  
Barbara E. Sabey ◽  
G. N. Lupton
Keyword(s):  
Skid Resistance ◽  
Correct Interpretation ◽  
Temperature Range ◽  
The Road ◽  
Test Conditions ◽  
Maximum Value ◽  
Rubber Compounds ◽  
Materials Used ◽  
Increasing Temperature ◽  
Styrene Butadiene

Abstract A laboratory investigation has been made into the variation with temperature of the hardness and resilience of a wide variety of rubber compounds of the tire tread type. The effect of hardness and resilience on the fractional properties of the compounds under wet conditions has also been studied. In the first series of tests the resilience and hardness of 25 compounds were measured over a temperature range 0° to 80° C. All were vulcanized tire tread type compounds, and the basic materials used comprised 14 natural rubbers, 7 styrene/butadiene (SBR) rubbers, 2 butyl, 1 polybutadiene, and 1 ethylene/propylene. The tests showed a marked increase in resilience with increasing temperature for all compounds except the polybutadiene; the hardness of all compounds changed very little with temperature, only a slight decrease being observed over the whole temperature rise. Nine compounds of representative resilience and hardness were selected for a second series of tests in which friction was measured over a temperature range 1° to 40° C on seven surfaces representing roads of different textures. For eight of the compounds, friction values decreased with increase in temperature; for the other compound the friction increased to a maximum value at 30° C. These changes in friction cannot be explained by changes in hardness of the compounds, but they are in accordance with resilience changes, taking into account the different test conditions obtaining in the friction and resilience tests. The friction tests also showed that with the portable skid-resistance tester used to measure friction the sharpness of the projections in the road surface is more important than their size in determining the friction values under wet conditions, even when rubber compounds of low resilience are used. The implications of the findings and their application to the study of friction between tire and road are discussed. In particular, they have a bearing on the correct interpretation of resilience measurements of tire tread materials in relation to friction values under wet conditions.

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