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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.

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.

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.

This SAE Recommended Practice indicates the location of the cast wheel mounting lug and the wheel disc on the rim in relation to the centerline of the tire.

This SAE Recommended. Practice provides uniform laboratory procedures for fatigue testing certain production disc wheels, spoke wheels, and demountable rims intended for normal highway use on trucks, buses, truck-trailers, and multipurpose passenger vehicles. Standardized fatigue tests are yet to be developed for wheels/rims not covered in this recommended practice.

This SAE Recommended Practice provides uniform laboratory procedures for fatigue testing certain production disc wheels, and demountable rims intended for normal highway use on trucks, buses, truck-trailers, and multipurpose passenger vehicles. This document does not cover bolt together divided wheels or other special application wheels and rims.

This SAE Recommended Practice provides uniform laboratory procedures for fatigue testing certain production disc wheels, wheels for demountable rims, and demountable rims intended for normal highway use on trucks, buses, truck-trailers, and multipurpose passenger vehicles. Standardized fatigue tests are yet to be developed for wheels and rims not covered in this recommended practice.

This SAE Recommended Practice includes wheel mounting elements subject to standardization in a series of industrial and agricultural disc wheels. The disc may be reversible or nonreversible and concave or convex. (See Figure 1 and Table 1.)

NEARLY 300 fleet operators were questioned by Mr. Laurie to gather data for this paper on what features the users of trucks would like to have the manufacturers incorporate in post-war trucks. The cooling system is one important item that came in for its share of criticism. For example, maintaining the proper coolant level is most important, and yet many of today's systems require filling into the filler neck before the liquid level can be seen. Petcocks or sight gages properly installed could solve this problem, according to Mr. Laurie. Accessibility for maintenance should also be improved in the post-war truck. Some of today's trucks have batteries that are not located for ease of servicing and spark plugs that it is almost impossible to remove and replace. Improvements should also be possible in cold starting of the engine, based on the experience of the Army in cold climates.

Can you become a visionary or are you born one? How does a visionary capture an opportunity and makes it a successful business? Are engineers more qualified to solve technical problems or run companies? SAE's "The Visionary's Take" addresses these and many other questions, by talking directly with those who have dared to tackle difficult engineering problems, and create real-life products out of their experience. In these short episodes, Sanjiv Singh and Lyle Chamberlain, respectively CEO and Chief Engineer from Near Earth Autonomy, talk about their experience in creating a brand-new company in the UAV world. Founded in 2011, Near Earth Autonomy brought together a group of engineers and roboticists, looking for unconventional solutions to very hard logistics problems, presenting danger to human life. The answers were developed by pushing technology to a higher level, testing quickly and often, and keeping an open mind to alternative ways of framing engineering challenges.

Can you become a visionary or are you born one? How does a visionary capture an opportunity and makes it a successful business? Are engineers more qualified to solve technical problems or run companies? SAE's "The Visionary's Take" addresses these and many other questions, by talking directly with those who have dared to tackle difficult engineering problems, and create real-life products out of their experience. In these short episodes, Sanjiv Singh and Lyle Chamberlain, respectively CEO and Chief Engineer from Near Earth Autonomy, talk about their experience in creating a brand-new company in the UAV world. Founded in 2011, Near Earth Autonomy brought together a group of engineers and roboticists, looking for unconventional solutions to very hard logistics problems, presenting danger to human life. The answers were developed by pushing technology to a higher level, testing quickly and often, and keeping an open mind to alternative ways of framing engineering challenges.

After many years of successful Visco fan drive applications, Behr has now transferred the Visco technology to the coolant pump drive. The continuously variable Visco drive allows the coolant pump to deliver the optimum flow dependent upon the requirements, therefore reducing the drive power to the minimum possible. Up to now coolant pumps, world wide, have almost always been powered by direct, uncontrolled drives. Consequently, the delivery and the power consumption have been directly related to the engine speed, which, in many conditions, results in an unnecessarily high flow rate. The potential to reduce the flow rate is inherent within the Visco coolant pump. As a concept with continuous control of the impeller speed it has been found to be more fuel efficient than incremental impeller speed control or concepts which only restrict or divert the flow rate. The torque transmission via the shear forces of a silicone oil results in a robust and wear-free drive unit.

Diesel exhaust aftertreatment solutions using injection, such as urea-based SCR and lean NOx trap systems, effectively reduce the emission NOx level in various light vehicles, commercial vehicles, and industrial applications. The performance of the injector plays an important role in successfully utilizing this type of technology, and the CFD tool provides not only a time and cost-saving, but also a reliable solution for extensively design iterations for optimizing the injector internal nozzle flow design. Inspired by this fact, a virtual test methodology on injector dosing rate utilizing CFD was proposed for the design process of injector internal nozzle flows.

Door slam test is one of the important durability tests in door design and development. Door requires to meet certain performance requirements like it should close properly (no metal to metal contact), there should not be any leakage, and closing operation should be smooth & with minimal effort and it should survive the life of the vehicle. Virtual simulation of door slam test, correlation with physical test results and effect of various parameters like seals stiffness are demonstrated in this study. Slam Analysis was carried out in LS-Dyna solver before physical test. This not only helped in avoiding initial structural design flaws, but also helped us in deciding door latch position, effect of mass distribution in the door and study of force distribution between primary seal, secondary seal and door latch. Primary and secondary seals played a critical role in the analysis. An intended length of both the seals was tested first to get its stiffness curve.

The existing instrumentation of a soil bin was retrofitted with virtual instrumentation techniques to achieve improved repeatability and more precise measurements. Current-loop sensors were added to the prime mover for improved speed control. Soil preparation operations were instrumented to determine penetrometer forces as a function of soil penetration depth, soil surface smoothness, compaction force, and soil surface elevation. Test hitch-points for agricultural implements were instrumented with wheatstone bridge force transducers. Implement depth was found with ratiometric linear transducers. Distance and speed determinations utilized an optical encoder with a resolution of 3.0 × 10-4 m. Temperature measurements were also recorded with solid state current transducers.

Vickers Discovery Series EMV Electrohydraulic Mobile Valve is one of the most advanced new products introduced by Vickers in 1996. The EMV is a four-way proportional flow control valve intended for Load Sensing systems. The concept is based on separated meter-in and meter-out valve elements in combination with several new technologies such as Valvistor, Anti-Saturation, Meter-in and Meter-out Pressure Control. The valve is microprocessor controlled, programmable and communicates via a CAN-Bus. The valve could easily be specified with an interactive Windows based configuration software.

This paper outlines the design philosophy and evaluation of the new “H” series variable displacement, medium pressure, open-circuit, axial piston hydraulic pumps. The “H” series is based on previously existing, technically successful, rotating group designs, but has significant design improvements affecting the areas of: Unit Weight Envelope Size Ease of Assembly, Disassembly, Repairability and Modification Alternate Fluid Capabilities The “H” series is a family of naturally aspirated pumps nominally rated at 250 or 275 bar (3625 or 4000 psig), depending on system operating parameters. The geometric displacements of the four units in the series are as follows: 57cc (3.5 cu. in./rev.) 74cc (4.5 cu. in./rev.) 98cc (6.0 cu. in./rev.) 131cc (8.0 cu. in./rev.)