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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 hazardous bulk chemical liquid cargo transportation is usually made through highways, using special automotive devices, named semitrailer tank, a kind of mobile tank specially developed to perform this task, manufactured with many types of steel, selected according to the chemical characteristics of the product to be transported. Equipment sizing is made based on specific standards which include specified formulas, loading, and safety factors representing the design criteria of this type of device. Despite of the detailed design criteria for semitrailer tank, it has been observed failure of some pieces of equipment during operation, in a shorter effective life than that one considered in the design phase itself. Considering a detailed study of the stress distribution in this type of equipment, this paper shows a verification of the possibility of yielding failure in the semitrailer tank structure.

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 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 construction, agricultural, and general purpose industrial categories of off-road self-propelled work machines as defined in SAE J1116.

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 construction, agricultural, and general purpose industrial categories of off-road self-propelled work machines as defined in SAE J1116.

SINCE 1954 the CIMTC Subcommittee has been engaged in a program to meet military requirements through industry's production of construction equipment which can give satisfactory cold weather performance down to temperatures of −65 F. Individual contracts for three crawler tractors and one motor grader were negotiated by ERDL for these projects, and their performance is discussed. Industry participation was subsequently expanded to include engineering tests in the cold weather conditions of the Mesabi Iron Range. This joint report of the Winterization Sub-committee of the CIMTC and ERDL Winterization Section consists of separate papers by various members and consultants of this Sub-committee and ERDL personnel.

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.

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.

An important emerging technical area is computer-based modeling of the various manufacturing processes that are used in many diverse industries. These models are used to optimize manufacturing techniques to reduce fabrication costs and improve the service performance. One manufacturing process important in steel fabrication is welding. It can be a useful tool to aid in reducing fabrication costs and service durability by optimizing the weld process and is the subject of this paper.

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.

Front under run protection device (FUPD) is a regulatory requirement for passive safety of N2 & N3 category vehicle. This device gives effective protection for small vehicles (M1 or N1 category) against under running of big vehicles (N2 & N3 category) in the event of a frontal collision. FUPD generally consists of the front under run protector (FUP) and its mounting structure. As the compliance load target for N3 category is high, the FUP required achieving regulation target need to have high rigidity. This increases its size and hence the weight, Increase in weight has impact on payload and cost. To curtail the weight of FUP, in general Aluminum with higher strength is in use, but use of Aluminum increases the cost. So the main challenge in FUPD design is to achieve the design with optimal system weight & cost.

Shift quality of a manual transmission is a critical characteristic that is requires utmost care by the designers while structuring the transmission. Shift quality is affected by many factors viz. synchronizer design, shift fork design, shifter design, gear design, transmission oil selection etc. Designers have realized that shift fork is critical element for improving shift feel of a transmission. This paper focuses upon the reduction in weight of the overall transmission shift system by using steel inserts in aluminum shifter forks. No compromise on the stiffness and strength of the shift fork of a manual transmission is done. Stiffness and strength of shifter fork is optimized using contact pattern analysis and stiffness analysis on MSC Nastran. All the subsystem (i.e. synchronizer and the shift system component) are constrained to optimize the shift fork stiffness. A 5-speed manual transmission is used as an example to illustrate the same.

The entire commercial vehicle industry is moving towards weight reduction to leverage on the latest materials available to benefit in payload & fuel efficiency. General practice of weight reduction using high strength steel with reduced thickness in reference to Roark’s formula does not consider the stiffness & dent performance. While this helps to meet the targeted weight reduction keeping the stress levels within the acceptable limit, but with a penalty on stiffness & dent performance. The parameters of stiffener like thickness, section & pitching are very important while considering the Stiffness, bucking & dent performance of a dumper body. The Finite Element Model of subject dumper body has been studied in general particularly on impact of dent performance and is correlated with road load data to provide unique solution to the product. The impact of payload during loading of dumper is the major load case.

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.

With increasing interest in more biodegradable and fire-resistant hydraulic fluids and with the availability of water-glycol hydraulic fluids suitable for high-pressure hydraulic pump operation, there is increasing interest in the conversion of mineral oil hydraulic systems to these alternative fluids. In this paper, the proper conversion procedures and troubleshooting of some common causes of hydraulic failures for the conversion of mineral oil hydraulic fluids to a water-glycol will be reviewed.

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.

One of the most commonly used tests to evaluate the antiwear properties of a hydraulic fluid is ASTM D 2882 which is based on a Vicker's V-104 vane pump. Although this is a commonly used test, the results are subject to numerous potential problems in both testing procedure and pump hardware. In this paper, the particular focus will be placed on potential problems that may be encountered with testing of water-glycol hydraulic fluids which may lead to erroneous and non-reproducible results.