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The coupling is an integral part of the Cummins CELECT electronically controlled injector. Excessive wear was observed on early designs of the coupling and coupling bore. The coupling wear was caused by a high stress concentration and excessive side loading of the coupling as it slid against the coupling bore. The zero wear theory was used to develop a coupling design where the maximum wear depth does not exceed half the peak to peak surface finish (zero wear) over the life of the engine. The side load exerted on the coupling was compared with the calculated contact pressure for zero wear. The undesirable effects of a square edge stress concentration are discussed in the zero wear model. The physical effects of the sharp edge and chamfered coupling edge are reported, but not analyzed in this paper. Three different coupling designs were investigated by applying the zero wear concept.

All around the world, steps are being taken to improve the quality of our environment. Prominent among these are the definition, implementation, and attainment of increasingly stringent emissions regulations for all types of engines, including off-highway diesels. These rigorous regulations have driven use of technologies like after-treatment, advanced air systems, and advanced fuel systems. Fuel dispensed off-highway is routinely and significantly dirtier than fuel from on-highway outlets. Furthermore, fuels used in developing countries can be up to 30 times dirtier than the average fuels in North America. Poor fuel cleanliness, coupled with the higher pressures and performance demands of modern fuel systems, create life challenges greater than encountered with cleaner fuels. This can result in costly disruption of operations, loss of productivity, and customer dissatisfaction in the off-highway market.

This SAE Standard specifies requirements and design guidelines for electrical wiring systems of less than 50 V and cable diameters from 0.8 to 19 mm2 used on off-road, self-propelled earthmoving machines as defined in SAE J1116 and agricultural tractors as defined in ASAE S390.

This SAE Standard specifies requirements and design guidelines for electrical wiring systems of less than 50 V and cable diameters from 0.35 to 19 mm2 used on off-road, self-propelled earthmoving machines as defined in SAE J1116 and agricultural tractors as defined in ASAE S390.

This SAE Standard specifies requirements and design guidelines for electrical wiring systems of less than 50 V and cable diameters from 0.35 to 19 mm2 used on off-road, self-propelled earthmoving machines as defined in SAE J1116 and agricultural tractors as defined in ASAE S390.

This report is concerned with the effects of braid angle on the behavior of hydraulic hose. For equilibrium conditions to exist, and if the braid layers are assumed to bear tension forces only, the angle of the reinforcement layers must be along that of the total force exerted by the internal pressure. This is the neutral angle θN, which has a theoretical value of 54.74° (54°44′). It is possible to hypothesize a fretting wear model in which wires move on top of one another inside a braid layer if the braid angle is different from this theoretical neutral angle. Even though theoretical claims are made by some technical professionals, the hydraulic hose industry has been successfully making hoses with non-neutral braid angles for years. Testing and application have shown that fretting wear is not a principal cause of hose failure and fatigue.

This SAE Recommended Practice provides minimum performance requirements and uniform laboratory procedures for fatigue testing of wheels and demountable rims intended for normal highway use on trucks, buses, truck-trailers, and multipurpose vehicles. For other wheels intended for normal highway use and temporary use on passenger cars, light trucks, and multipurpose vehicles, see SAE J328. For wheels used on trailers drawn by passenger cars, light trucks, or multipurpose vehicles, see SAE J1204. For bolt together military wheels, see SAE J1992. This document does not cover other special application wheels and rims.

This SAE Recommended Practice provides minimum performance requirements and uniform laboratory procedures for fatigue testing of wheels and demountable rims intended for normal highway use on trucks, buses, truck-trailers, and multipurpose vehicles. For other wheels intended for normal highway use and temporary use on passenger cars, light trucks, and multipurpose vehicles, see SAE J328. For wheels used on trailers drawn by passenger cars, light trucks, or multipurpose vehicles, see SAE J1204. For bolt together military wheels, see SAE J1992. This document does not cover other special application wheels and rims.

This SAE Recommended Practice provides minimum performance requirements and uniform laboratory procedures for fatigue testing of disc wheels, demountable rims, and bolt-together wheels intended for normal highway use on military trucks, buses, truck-trailers, and multipurpose vehicles. For wheels and rims intended for normal highway use by trucks, see SAE J267. For wheels intended for normal highway use by passenger cars, light trucks, and multipurpose vehicles, see SAE J328. For wheels used on trailers drawn by passenger cars, light trucks, or multipurpose vehicles, see SAE J1204. This document does not cover off-highway or other special application wheels and rims.

This SAE Recommended Practice provides minimum performance target and uniform laboratory procedures for fatigue testing of wheels and demountable rims intended for normal highway use on trucks, buses, truck-trailers, and multipurpose vehicles. Users may establish design criteria exceeding the minimum performance target for added confidence in a design. The cycle target noted in Tables 1 and 2 are based on Weibull statistics using two parameter, median ranks, 50% confidence level and 90% reliability, and beta equal to two, typically noted as B10C50. For other wheels intended for normal highway use and temporary use on passenger cars, light trucks, and multipurpose vehicles, refer to SAE J328. For wheels used on trailers drawn by passenger cars, light trucks, or multipurpose vehicles, refer to SAE J1204. For bolt together military wheels, refer to SAE J1992. This document does not cover other special application wheels and rims.

This SAE Recommended Practice provides minimum performance requirements and uniform laboratory procedures for fatigue testing of wheels and demountable rims intended for normal highway use on trucks, buses, truck-trailers, and multipurpose vehicles. Users may establish design criteria exceeding the minimum performance requirement for added confidence in a design. The cycle requirements noted in Tables 1 and 2 are based on Weibull statistics using 2 parameter, median ranks, 50% confidence level and 90% reliability, and beta equal to 2, typically noted as B10C50. For other wheels intended for normal highway use and temporary use on passenger cars, light trucks, and multipurpose vehicles, see SAE J328. For wheels used on trailers drawn by passenger cars, light trucks, or multipurpose vehicles, see SAE J1204. For bolt together military wheels, see SAE J1992. This document does not cover other special application wheels and rims.

The SAE Recommended Practice establishes minimum performance requirements and related uniform laboratory test procedures for evaluating lateral (curb) impact collision resistance of all wheels intended for use on passenger cars and light trucks.

Wheel hubs with drum brakes of heavy-duty vehicles rarely broke, but some suddenly cracked in the 2000s. The cause of damage was said to be a lack of hub strength. However, the case was suspicious because the hubs were produced according to the design guidelines by the JSAE. In the 1990s, brake shoe-lining materials were changed from asbestos to non-asbestos for people’s health. The brake squeal and abnormal self-lock frequently occurred because of the increased friction coefficient between drum and shoe lining in the case of the leading–trailing type. The mechanical friction coefficient changes with the material and the contact angle, which varies with the wear of shoe lining and the drum temperature. In the previous report, the deformation of the wheel hub under the abnormal self-lock was verified by observing the change of hub attitude in model test equipment.

Abstract The use of appropriate loads and regulations is of great importance in weld fatigue assessment of rail on-track maintenance equipment and similar vehicles for optimized design. The regulations and available loads, however, are often generalized for several categories, which proves to be overly conservative for some specific categories of machines. EN (European Norm) and AAR (Association of American Railroads) regulations play a pivotal role in determining the applicable loads and acceptance criteria within this study. The availability of track-induced fatigue load data for the cumulative damage approach in track maintenance machines is often limited. Consequently, the FEA-based validation of rail track maintenance equipment often resorts to the infinite life approach rather than cumulative damage approach for track-induced travel loads, resulting in overly conservative designs.

Welding has been used extensively in automotive components design due to its flexibility to be applied in manufacturing, high structural strength and low cost. To improve fuel economy and reduce material cost, weight reduction by optimized structural design has been a high priority in auto industry. In the majority of heavy duty vehicle's chassis components design, the ability to predict the mechanical performance of welded joints is the key to success of structural optimization. FEA (finite element analysis) has been used in the industry to analyze welded parts. However, mesh sensitivity and material properties have been major issues due to geometry irregularity, metallurgical degradation of the base material, and inherent residual stress associated with welded joints. An approach, equilibrium-equivalent structural stress method, led by Battelle and through several joint industrial projects (JIP), has been developed.

Wear characteristics of four bearing materials have been investigated under different sliding conditions. The bearing materials used were CDA 954, CDA 863, CDA 932, and CDA 938. Using a Taber Wear Tester, a cylinder on a flat geometry was used as a tribo contact pair. All bearing materials in the form of a thick cylindrical disk were subjected to combined sliding-rolling motion against a rotating flat disk. The flat disk was either an abrasive disk, or a very soft steel disk, or a hardened steel disk with and without lubrication. Wear was measured as weight loss after several thousand cycles of rotation. Maximum wear of the bearing materials occurred when the counter body was a very soft steel disk. These results together with the wear rate of each bearing material sliding against four different counter bodies are presented. These results are found to be of practical importance in the design and application of journal bearings made of materials used in this investigation.

The exhaust valve system of combustion engines experiences a very complex contact situation of frequent impact involving micro sliding, high and varying temperatures, complex exhaust gas chemistry and possible particulates. The wear rate has to be extremely low, and the individual wearing events operate at a scale that is very demanding to detect. The tribological conditions in the exhaust valve system are expected to become even worse for engines that will follow the future emission regulations. The regulations demand reduced amounts of soot and particles, sulfur compounds, etc., which today act beneficial for the seating surfaces. The reductions are expected to increase the metal-to-metal contact.

Off-road dump truck body is exposed to abrasive wear during handling of granular materials. The wear rate of body of dump truck has direct influence on maintenance and replacement during its service process. In this paper the discrete element method (DEM) is used to simulate the granular materials of dump truck. The wear of body floor during one dumping process can be achieved by cosimulation of FEM-DEM. The wear depth variation of body has the stochastic characteristic which can be modeled by Geometric Brownian Motion (GBM). The two parameters in the stochastic differential equation, drift coefficient and diffusion coefficient, can be estimated by the wear depth measuring data. It is possible to quantitatively predict the wear evolution of every grid point of the body floor by solving this stochastic differential equation. The simulation result of the wear model is helpful to optimize design of off-road dump truck body.

This paper is concerned with the synergistic effects of pump wear modes. The objective is to investigate the wear produced by cavitation, adhesion, abrasion, and corrosion and to verify a proposed model of the synergistic pump wear process. The approach followed includes identification of the combined effects of different wear modes (synergisms) in a pump and the development of a synergistic wear model that includes pump operating and environmental conditions as trigger factors of wear modes. An experimental program was designed to evaluate the cavitation, adhesion, and corrosion wear effects in conjunction with the abrasive wear produced in a pump by measuring wear debris, particle size and gravimetric levels of fluid. The generation of wear was traced to different pump locations. The results obtained here suggest that improved pump design and longer pump service life can be obtained when synergisms between failure modes are properly understood.

This study investigates the wear characteristics of a variable valve timing (VVT) system used to vary the phasing of the inlet valve events on a medium speed marine diesel engine. The running-in properties of critical components within the system are examined. The effect of surface finish and surface hardness upon wear is examined. It was found that in order to prevent excessive wear between the roller and tappet follower then the roller should be harder than the tappet. Tappet and roller hardness values of 60 and 70 Rockwell Hardness ‘C’ (HRC) respectively were found to be satisfactory.