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Affordable, efficient and durable catalytic converters for the Commercial Vehicle and Non-Road industry in all countries are required to reduce vehicle emissions under real world driving conditions and fulfill future legal requirements. Specially for India traffic conditions and payload to engine size conditions new cost-effective solutions are needed to participate in a cleaner and healthier environment. Metallic substrates with structured foils like the Transversal StructureTM (TS) or the Longitudinal StructureTM (LS) have been proved to be capable of improving conversion behavior, even with smaller catalyst size. Now Vitesco Technologies is developed a new Substrate for Heavy duty applications that specifically maintains the geometric surface area at a very high level and improves further the mass transport of the pollutants, which potentially leads together to very high pollutant conversion rates.

Design of a Cabin Tilting System of heavy trucks, a multi degree of freedom mechanism, is a challenge. Factors like adequate tilting angle, cabin styling, packaging, non interference of tilting system with ride comfort, forces in the system, specifications of the hydraulic system, are all very important for designing the system. Numerous considerations make the design process highly iterative hence longer design time. This paper primarily focuses on Kinematics and Dynamic analysis of the system in ADAMS and validation of system with real time testing results. Intention of this work is to make a parametric ADAMS model and link it to a Knowledge Based Engineering application to facilitate designer to quickly carry out design iterations for reducing development time. The Knowledge Based Engineering software is made using object oriented language called ‘Object Definition Language’ which has been developed using C and C++ software languages.

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.

The idea of a world truck is a fascinating challenge - whereas cars are purchased more or less as seen; truck purchasers demand more individual configurations. In national and global terms, that means a highly complex truck market. Historically, a few European and North American manufacturers produced almost all the trucks for the world market. That changed through the 60's and 70's, with more local assembly plants around the world and increasing worldwide manufacturing capabilities. Concurrently, international component design standards have made some progress towards compatibility. Much greater co-operation is needed, however, before a genuinely international set of standards can be applied. As the task assigned to trucks is the same worldwide, namely to transport goods from A to B; it should be desirable and possible to work towards a greater commonality of vehicle - to ultimately achieve a world truck. The only unknown is the time scale.

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.

Work solenoids are widely used in household appliances. The environment and design of this type application does not lead to solenoids for the earthmoving industry. This paper presents the environmental effects to be considered when designing a solenoid for the earthmoving industry. It further explains the need for, and type of, test necessary to validate the design. Finally a review of production quality procedures, necessary to insure reliable production parts is discussed.

Knitted wiremesh along with radial gas tight seals provide reliable mounting system for low temperature underbody converters. The compression characteristics of the wiremesh is modified by wire material, wire diameter, wire geometry, mesh crimp heights; wire density, wiremesh courses per inch, needle count, number of strands, wiremesh temper, wiremesh surface profile and surface characteristics. The radial mounting pressure provided by the wiremesh is matched with the mounting pressure requirement. Wiremesh systems can be tailored to any required radial mounting pressure from conventional to ultra thin-wall substrates. The wiremesh mounting system is proven durable, without any failure on more than 25 million underbody converters in light duty vehicles. Cp and Cpk show the capability of the manufacturing process. Thus the wiremesh mounting support is a viable alternate for low temperature gasoline and diesel applications.

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.

The development of this vehicle is described from concept, through design and assembly. The design intent of this unique vehicle was high fuel efficiency, good ride and handling characteristics, and a high degree of passenger safety at a competitive cost. A combination of some of the latest in automotive and motor home construction technology was used to meet the desired goals.

To investigate the feasibility of various test procedures to determine aerodynamic performance for the Phase 2 Greenhouse Gas (GHG) Regulations for Heavy-Duty Vehicles in the United States, the US Environmental Protection Agency commissioned, through Southwest Research Institute, constant-speed torque tests of several heavy-duty tractors matched to a conventional 53-foot dry-van trailer. Torque was measured at the transmission output shaft and, for most tests, also on each of the drive wheels. Air speed was measured onboard the vehicle, and wind conditions were measured using a weather station placed along the road side. Tests were performed on a rural road in Texas. Measuring wind-averaged drag from on-road tests has historically been a challenge. By collecting data in various wind conditions at multiple speeds over multiple days, a regression-based method was developed to estimate wind-averaged drag with a low precision error for multiple tractor-trailer combinations.

A 1:10-scale wind tunnel development program was undertaken by the National Research Council of Canada and Airshield Inc. in 1994 to develop trailer side skirts that would reduce the aerodynamic drag of single and tandem trailers. Additionally, a second wind tunnel program was performed by the NRC to evaluate the fuel-saving performance of boat-tail panels when used in conjunction with the skirt-equipped single and tandem trailers. Side skirts on tandem, 8.2-m-long trailers (all model dimensions converted to full scale) were found to reduce the wind-averaged drag coefficient at 105 km/h (65 mi/h) by 0.0758. The front pair of skirts alone produced 75% of the total drag reduction from both sets of skirts and the rear pair alone produced 40% of that from both pairs. The sum of the drag reductions from front and rear skirts separately was 115% of that when both sets were fitted, suggesting an interaction between both.

A wind tunnel experiment has been conducted to determine the changes in drag and side force due to the presence and position of cab extenders on a model of a commercial tractor-trailer truck. The geometric variables investigated are the cab extenders angle of incidence, the tractor-trailer spacing and the yaw angle of the vehicle. Three cab extender angles were tested-0°, 15° (out) and -15° (in) with respect to the side of the tractor. The cab and trailer models have the same width and height. The minimum drag coefficient was found for the tractor and trailer combination when the cab extenders were set to 0° angle of incidence with respect to the headwind. This result holds for all yaw angles with moderate gap spacing between the tractor and trailer. This study suggests that commercial tractor-trailer trucks can benefit from adjustable cab extender settings; 0° when using a trailer and -15° when no trailer is used.

The use of devices to reduce aerodynamic drag on large trailers and save fuel in long-haul, over-the-road freight operations has spurred innovation and prompted some trucking fleets to use them in combinations to achieve even greater gains in fuel-efficiency. This paper examines aerodynamic performance and potential drag reduction benefits of using trailer aerodynamic components in combinations based upon wind tunnel test data. Representations of SmartWay-verified trailer aerodynamic components were tested on a one-eighth scale model of a class 8 sleeper tractor and a fifty three foot, van trailer model. The open-jet wind tunnel employed a rolling floor to reduce floor boundary layer interference. The drag impacts of aerodynamic packages are evaluated for both van and refrigerated trailers. Additionally, the interactions between individual aerodynamic devices is investigated.

The trucking industry is being encouraged by environmental and cost factors to improve fuel efficiency. One factor that affects fuel efficiency is the aerodynamic design of the vehicles; that is, the vehicles with lower aerodynamic drag will get better mileage, reducing carbon emissions and reducing costs through lower fuel usage. A significant tool towards developing vehicles with lower drag is the wind tunnel. The automobile industry has made great improvements in fuel efficiency by using wind tunnels to determine the best designs to achieve lower drag. Those wind tunnels are not optimum for testing the larger, longer heavy trucks since the wind tunnels are smaller than needed. The estimated costs for a heavy truck wind tunnel based on automotive wind tunnel technology are quite high. A potential nozzle concept to reduce wind tunnel cost and several other new possible approaches to lower wind tunnel costs are presented.

HIGH output per cubic inch of piston displacement is desirable not alone for the purpose of being able to transport more payload faster, but more particularly for the invariably associated byproduct of lower specific fuel consumption, and especially at road-load requirements. The only way of accomplishing this purpose is through the use of higher compression ratios, and the limiting factors for this objective are fuel distribution and the operating temperatures of the component parts. A manifold is proposed which not only definitely improves distribution at both full and road loads, but has the inherent additional advantage of reducing the formation of condensate, thus still further facilitating a reduction in road-load specific fuel consumption. Hydraulic valve lifters, obviation of mechanical and thermal distortion, and controlled water flow are the essentials in improved cooling.

The wheel motor is a combination of hydro-motor and planetary transmission. Industrial, agricultural, construction and various types of public utility vehicles, which due to their design cannot use axle drives, make increasing use of the individual wheel drive. Speed, torque transmission, wheel bearings, valves for hydraulic operation and hydraulic engagement/disengagement are some of the requirements for wheel motor drives.

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.

In Automotive, Steel wheels are exponentially replaced by Aluminum wheels because of its feather light, agile performance and better acceleration. One such widely used size is 11.75 x 22.5 wheels for trucks and trailer segment. During the design stage of 11.75 x 22.5 wheel, the valve hole was placed away from the stress concentration zone to reduce the stress on the holes and also the design was validated through all conventional wheel rim testing methodologies (Like CFT, RFT and Bi-axial) and the wheel passed all the test requirements. During the field trials, failures were observed on the valve holes, despite of this hole was away from stress concentration region. Understood from the field trials that, the regular testing was not able to simulate the real field conditions for this particular size and changed the boundary condition in our FEA to simulate the actual conditions. After changing the boundary conditions, we could able to observe more stress in valve hole.

New technology placed on specific components within the wheel end system, required modifications to existing tapered wheel bearing adjustment procedures. A new method for vehicles, which use tapered roller bearings, required a procedure addressing new technologies for the wheel end system. OEM and service technicians would benefit from concise procedures. Technologies engineered and developed for ABS (Anti-skid Brake Systems), extended brake blocks and synthetic lubricants, required research for the data base. Research to optimize the operating environment through improved maintenance procedures helped in achieving optimum wheel system operation. A tapered wheel bearing adjustment procedure and visual chart are the results profiting the vehicle manufacturers and field service technicians.

This paper describes how the needs of the truck end-user have changed under the pressures of deregulation and competition, and how the truck supply community has responded. It observes that traditional management and hardware responses are yielding diminishing improvements. Significant further improvement is postulated based on application of electronic technology to functional control of a “truck system”. This is defined as a technological discontinuity where a new perspective, “thinking systems” will be needed. The post-1995 truck system is described; and what “thinking systems” entails and “how to create a system” are discussed. It is further postulated that this change in technology will have major impacts on the structure of the truck manufacturing industry, and the capabilities required of its management and technical communities.