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Due to ever soaring fuel costs and even more stringent emission regulations which require more elaborate technical efforts and unfortunately lead to a negative trend on fuel economy as well, todays and future trucking business is extremely challenged. These facts create an urgent requirement for the engine manufacturer to offer an engine with an optimized cost-benefit-ratio for the trucking business. Mercedes-Benz, as the leader in the European commercial vehicle market - of which e. g. high fuel costs, long maintenance intervals and high engine power-to-weight ratios have always been key characteristics - has developed a new class 8 engine for the US market. The MBE 4000 is a 6 cylinder inline engine in the compact size and low weight category, but due to its displacement of 12,8 liters it offers high performance characteristics like heavier big block engines.

Cyclic oligomers of butylene terephthalate (CBT™)† represent a new chemical route to semi-crystalline thermoplastic polybutylene terephthalate (PBT). The oligomers of interest melt completely at about 150°C to produce a low viscosity fluid that is ideal for wetting and dispersing fibrous fillers and reinforcements thereby enabling the development of composites that were previously not possible when working with high viscosity commercial PBT. Introduction of catalyst to undiluted molten cyclic oligomer leads to rapid ring opening polymerization and the formation of high molecular weight thermoplastic PBT without the generation of volatile organic compounds. The polymer resulting from this polymerization will be hereby referred to as pCBT. Treatment of cyclic oligomers in this fashion results in pCBT thermoplastic resin with a high melting point (230°C) and physical performance similar to that of other commercially available PBT resins.

GREATER ease of servicing is one of the ultimate goals in the development of dry-type air cleaners. The authors acknowledge, however, that the oil-bath cleaner is a rugged proved component that has done a good job for the farmers who serviced it properly. This paper describes studies made in Illinois of oil-bath and dry air cleaners in field service. At the same fuel/air ratios, the maximum horsepower of a test engine was greater with the dry-type filter than with the oil-bath cleaner. It was found that with AC fine dust and steady airflow, the oil-bath cleaners had significantly lower efficiencies than the dry-type filter. At less than rated airflow the efficiency of the oil-bath cleaner decreased while that of the dry filter remained high.

This paper describes the ZF - Intarder, a wear-free vehicle brake for commercial vehicles. Qualities such as optimum weight saving, compactness, compatibility with all PTOs and no change in driveshaft length, are the results of a new development. Performance measurements demonstrate connection with engine cooling system. Field test measurements provide new information about frequency of use of various brake levels and electronic speed control. An evaluation of financial issues indicates advantages for operation.

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.

The published SAE J2954 standard established an industry-wide specification that defines acceptable criteria for interoperability, electromagnetic compatibility, EMF, minimum performance, safety, and testing for wireless power transfer (WPT) for light-duty plug-in electric vehicles. This SAE Information Report, SAE J2954/2, defines new power transfer levels in the higher power ranges needed for heavy-duty electric vehicles. This document addresses the requirements based on these charge levels and different vehicle applications as a first step in the process of completing a standard that the industry can use, both for private (fleet) and public wireless power transfer, including for charging electric vehicle batteries. This document is the first step in a process towards HD static and dynamic WPT. This document lacks specific requirements and solutions, for which field data is needed.

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 establishes uniform test procedures and performance requirements for the defrosting system of enclosed cab trucks, buses, and multipurpose vehicles. It is limited to a test that can be conducted on uniform test equipment in commercially available laboratory facilities. Current engineering practice prescribes that for laboratory evaluation of defroster systems, an ice coating of known thickness be applied to the windshield and left- and right-hand side windows to provide more uniform and repeatable test results, even though under actual conditions such a coating would necessarily be scraped off before driving. The test condition, therefore, represents a more severe condition than the actual condition, where the defroster system must merely be capable of maintaining a cleared viewing area.

The effect of eight installation and component parameters on cooling system heat rejection and air flow were examined in detail in a wind tunnel facility. A quarter-replicate, two level factorial test plan was followed. Within the ranges of each parameter tested, the fan characteristics and the projection of fan into the shroud are highly significant parameters. The fan to radiator distance, the radiator characteristics, and the fan tip to shroud clearance are significant parameters. The fan to engine block distance and the type of shroud are not significant parameters.

Cast iron is generally thought of as a weak, dirty, cheap, brittle material that does not have a place in applications requiring high strength and defined engineering properties. While gray cast iron is relatively brittle by comparison with steel, ductile iron is not. In fact, ductile iron has strengths and toughness very similar to steel and the machinability advantages make an attractive opportunity for significant cost reductions. Gray and ductile iron bar stock is commercially available and can be used as a direct replacement in applications that are currently being made from carbon steel bar. Ductile iron bar stock conversions are very prevalent in many fluid power applications including glands and rod guides, cylinders, hydrostatic transmission barrels and in high-pressure manifolds. Automotive gears are being converted to ductile iron for its damping capacity and cost reductions.

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.

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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.

Weight reduction in construction equipment is sought to achieve energy conservation and also to comply with the vehicle safety and compliance regulations, managing the weight distribution across the rear and the front end of the equipment to achieve the optimum balancing. Of late the thrust on product weight has increased along with reduced time to market, leading to increased usage of structural optimization methods. This has been further supported by the availability of high performance computing at relatively low cost. VOC and CTQ tools provided the motivation and initial screening of the design variables. The structural optimization software provides an integrated platform for analysis as well as optimization of components. In this work, an optimization tool has been used for size and shape optimization of a construction equipment assembly and a commercial FEA package was used for verification and validation of the results.

The environmental impact from herbicide utilization has been well documented in recent years. The reduction in weed control with out a viable alternative will likely result in decreased per acre production and thus higher unit production cost. The potential for selective herbicide application to reduce herbicide usage and yet maintain adequate weed control has generated significant interest in different forms of remote sensing of agricultural crops. This research evaluated the color co-occurrence texture analysis technique to determine its potential for utilization in crop groundcover identification. A program termed GCVIS (Ground Cover VISion) was developed to control an ATT TARGA 24 frame grabber; and generate HSI color features from the RGB format pixel data, HSI CCM matrices and the co-occurrence texture feature data.

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.

Axial piston type pumps are often exposed to severe operating conditions because of the duty cycle, the environment, or, in some situations, poor maintenance and even abuse. The detrimental effects on the pump and the hydraulic system as a result of these adverse conditions are often not known or predictable. In this study, four controlled severe operating conditions were imposed on four identical axial piston type pumps. They included 1) constant high load pressure and normal fluid temperature, 2) constant high load pressure and elevated fluid temperature, 3) cyclic load pressure and normal fluid temperature, and 4) cyclic load pressure and elevated fluid temperature. The tests were long-term; they were run continuously for up to 5000 hours. The pump wear was monitored in all cases using ferrography. In addition, the condition of the fluid was monitored and the circuit filters were examined periodically. The results of the findings are presented in this paper.

Hydraulic fluid performance, including water-glycols (W/G), is dependent on the chemical composition of the fluid and cleanliness. An overview of W/G fluid chemistry on pump wear is provided here. Also provided, is a brief overview of the impact of fluid cleanliness on the potential wear properties of various components. Finally, an overview of recommended analytical procedures to assure adequate long-term fluid hydraulic and lubrication performance is provided. If these procedures are followed, substantial improvements in hydraulic pump longevity and performance will be realized.

This SAE Standard specifies minimum performance and test criteria for brake systems to enable uniform assessment of the braking capability of walk-along self-propelled work machines with a mass greater than 115 kg. Service and parking brake systems are covered by this document.

This SAE Standard specifies minimum performance and test criteria for brake systems to enable uniform assessment of the braking capability of walk-along self-propelled work machines with a mass greater than 115 kg. Service and parking brake systems are covered by this document.