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A family of logic-based radio-controlled components, engine speed sensors, and industrial magnetic pulleys suitable for the most severe applications found in the environmental management industries has been developed. The relay logic boards are user friendly and user ready for an unlimited array of output to match OEM's ever-changing demand. The speed sensors relieve the engine power plant and drive components of unnecessary abuse when the plant is under a heavy load. The industrial magnetic head pulleys are a “new breed” of ceramic magnet that create a unique magnetic field capable of removing a large percentage of ferrite metal from waste wood grinding.

An appropriate test procedure, based on a duty cycle representative of real in-use operation, is an essential tool for characterizing engine emissions. A study has been performed to develop and validate a snowmobile engine test procedure for measurement of exhaust emissions. Real-time operating data collected from four instrumented snowmobiles were combined into a composite database for analysis and formulation of a snowmobile engine duty cycle. One snowmobile from each of four manufacturers (Arctic Cat, Polaris, Ski-Doo, and Yamaha) was included in the data collection process. Snowmobiles were driven over various on- and off-trail segments representing five driving styles: aggressive (trail), moderate (trail), double (trail with operator and one passenger), freestyle (off trail), and lake driving. Statistical analysis of this database was performed, and a five-mode steady-state snowmobile engine duty cycle was developed.

In the last two decades we have literally became a global society in all aspects of technology. Unfortunately, this has caused us to “race” to stay competetive and consistent in our desires to remain in this technological race. Any time an accelerated pace is demanded, mundane things are often overlooked. This becomes the basis for many lost opportunities.

This paper will describe the history of gear oils and how they have evolved over the years to provide the protection required with the extended oil change intervals demanded in today's heavy-duty commercial vehicles. It will also highlight the development of an oil that satisfies the current needs of the axle for an extended length of time, and also meets the extremely demanding requirements of the manual transmission. This paper will provide a comparison of photos and test results obtained with this “single barrel” lubricant to those obtained with traditional gear oil formulations.

Noise emitted from the pump can be a major influence on the overall noise created by a power steering system. Dynamic simulation can aid the designer by showing the effect of the pump geometry and oil properties on noise before the prototype has been built. This paper discusses a simulation of suction port flow ripple in a power steering vane pump, which is validated against experimental data. Results show that the mean pressure in the delivery line affects the amplitude of suction port flow ripple. Internal leakage in the pump was found to have little effect on suction port flow ripple. The level of high-frequency flow ripple from the suction port was found to be comparable with or greater than that from the delivery port. The simulation is used to recommend the addition of relief grooves to reduce the high-frequency flow ripple.

Currently, the industry standard pump test which is used to evaluate the lubricating performance of hydraulic fluids is ASTM D-2882 [1,2]. This test, and others, utilizes the Vickers V-104 vane pump [3]. Although ASTM D-2882 has been an industry standard for many years, it does not provide the necessary correlation required for prediction of the lubricating properties of a hydraulic fluid in various piston pump operations. The objective of this paper is to detail the recently proposed Rexroth Piston Pump Test which is being proposed as an ASTM standard. A description of the proposed hardware, pump testing strategies and methods of standardized wear determination will be provided.

This paper addresses a common problem associated with data analysis when a 1st failure in n, Weibull analysis is used. This is known among Weibull practitioners as the method of “sudden death”. Weibull analysis is a widely used reliability assessment and prediction technique. The “sudden death” method was initially developed to help reduce test time. In a “sudden death” test, k groups of n parts each are tested. In each test group testing is halted when the first failure occurs. This is referred to as the “first failure in n” and is usually detected by periodic inspection or by automatic/electronic test shut-off when the first failure occurs. It may happen that the first failure is not detected and there are two or more failures found upon inspection. In such cases the first failure time is lost since there are now 2 or more failures. If the second or third failure time is used as if it were the first failure time, overestimation of the reliability will result.

For most rolling element bearings used in practical applications, the permissible speed is defined as the bearing speed corresponding to a certain assumed limiting operating temperature in the bearing. Prediction of bearing permissible speed requires a thermal balance analysis considering 1) bearing heat generation (or torque) and 2) the heat dissipation of the bearing system, which is a function of ambient temperature, housing material and geometry and its heat transfer parameters. Recent results of running torque measurement of needle roller bearings and other types of roller bearings have been reviewed and compared with the well known Palmgren's prediction. The experimentally based formula for bearing power loss for needle bearings is used in the heat balance analysis for determining bearing reference and permissible speed. The calculated reference speed is compared with the DIN calculated reference speed using Palmgren's formula.

To obtain the simplified formula of viscous rolling resistance in the roller-raceway contact of tapered roller bearings, full EHD analyses in line contacts have been carried out for a wide range of dimensionless EHD parameters and meniscus distances in the inlet region. The results show that the effects of G and W on the viscous rolling resistance under full flooded conditions are small. However, the effects of U, G and W are influenced by the meniscus distance. The formula for frictional torque taking into account the simplified formula has been compared to the frictional torque obtained from experiment.

A new test method has been developed that enables the resistance to through cracking of different bearing materials operating under the influence of hoop stress to be assessed. Using this method the resistance to through cracking of a new case hardened medium carbon bearing steel together with standard through hardened SAE 52100 and case hardened SAE 5120 bearing steels has been assessed. The results showed that the new case hardened medium carbon and SAE 5120 steels had a higher resistance to through ring cracking than the through hardened SAE 52100 steel at a given hoop stress. The results also showed that the resistance to through cracking of the new case hardened medium carbon steel was similar to that of SAE 5120 steel.

Cavitation is the dynamic process of gas cavity growth and collapse in a liquid. These cavities are due to the presence of dissolved gases or volatile liquids and they are formed at the point where the pressure is less than the saturation pressure of the gas (gaseous cavitation) or vapor pressure (vaporous cavitation). In this paper, various hydraulic system design factors and fluid properties affecting the cavitation process, and bubble collapse mechanisms will be discussed. In-situ generation of cavitation, examination of the cavitation process in model hydraulic systems, material effects and test methods will be reviewed.

Thermal distortions of friction disks caused by frictional heating modify pressure distribution on friction surfaces. Pressure distribution, in turn, determines distribution of generated frictional heat. These interdependencies create a complex thermoelastic system that, under some conditions, may become unstable and may lead to severe pressure concentrations with very high local temperature and stress. The phenomenon is responsible for many common thermal failure modes of friction elements and is known as frictionally excited thermoelastic instability (TEI). In the paper, one of the cases of TEI is investigated theoretically and experimentally. The study involves a two-disk structure with one fiction disk and one matching steel disk that have one friction interface. An unsteady heat conduction problem and an elastic contact problem are modeled as axisymmetric ones and are solved using the finite element method.

For vehicle transmissions, limited slip devices, and brakes employing wet friction elements, there are growing demands for improvements in reliability, performance and durability. In order to meet the requirements, it is essential to improve the paper type wet friction material applied to such mechanical devices. Remarkably, the durability of the paper is most important because it directly determines the life of the devices. This article presents advanced paper type wet friction materials which have achieved both greater heat resistance and the mechanical fatigue resistance strength, together. Additionally, this article refers to development of Non-paper type friction materials with three dimensional structure to meet the highest durability demands.

Under constant pressure through both national and EC-wide regulations as well as increased consumer awareness the automotive industry has become more and more concerned with improving the environmental profiles of its products. Namely the end-of-life aspects have been pushed into the center of interest. Trying to minimize disassembly cost and to increase potential revalorisation profits, companies strive to integrate environmental constraints early in the design phase. This paper describes how Life Cycle Assessment (LCA) and Design for the Environment (DFE) respectively contribute towards the objective of improved environmental profiles of automotives and especially the handling of end-of-life vehicules.

Cars cause a lot of pollutants during the utilization phase. Within the last years environmental legislation tried to reduce the emissions by the introduction of very tight laws. The results are impressive: Most of the car exhaust emissions like carbonmonoxid and nitrous oxides have been reduced. At this stage new emission reduction limits in Europe as well as in the United States can only be achieved if the formulation of the catalyst system is significantly changed. An increased use of precious metals and rare earth materials is the result of such a modification which succeeds in a more expensive design of the total catalyst systems. More expensive means not only cost aspects but also the environmental burdens related to the increased production of precious metals and other catalyst components. The Life Cycle Engineering (LCE) of the catalyst system which achieves the new legislation is demonstrated as well as the effects to the usage phase.

With the change of the state structure has also changed spending power, the development of private property and businesses, which had a big influence on the dimension and structure of the vehicle fleet. In Slovakia, where the average age of the road motor vehicles is higher than the projected durability, intensity of innovation can essentially lower the negative influences of motorism. In the paper there are analysed factors, mainly the possibility of lowering emissions through lowering the average age of vehicles, domestic possibilities and import of motor vehicles, solvency of the population and also through improving of technical conditions and holding on emission standards.

LCA. is becoming one of the main instruments for isolating environmentally winning alternatives in industrial decisions. It is also true that in the car industry decisions have to be taken more and more quickly since the time to market in the last years has been strongly reduced. This is one of the reasons that fast LCA. techniques are being taken in consideration. This work illustrates some guidelines for fast LCA. techniques to be used, in well defined situations, for evaluating different recycling opportunities.

One of the problems of a LCA is the complexity of the considered systems. Results depending strongly on the boundary conditions. More appropriate is to parameterise the LCA and enable it for variations. With that, the Life Cycle Modeling and Simulation leads to a deeper understanding of the examined system. Design parameters, like the geometry or the material of the part can be varied as well as the mass and energy flow in the process chain or methodological parameters. This is especially necessary in the early stage of the design process as a tool for sensitivity analysis and optimisation of products. A dominance analysis ensures that the complexity of the model is suitable for goal and scope of the study.

With regard to the development and quality control of slip-controlled multi-disc clutches, different test procedures were previously used in Europe. These employed test procedures are presented and the requirements for future systems outlined. A new test bench concept is presented, which allows all the necessary procedures previously performed on separate test benches to be performed on a single test bench. This allows considerable time and money savings to be made during development and quality control of slip-controlled multi-disc clutches and transmission oils. Suppliers are presented with the opportunity to perform all the required tests themselves.

A new PC-based hardware and software system has been developed to automate the data acquisition and analysis of brake noise and vibration. The system integrates advanced signal conditioning and software to acquire data rapidly in a consistent and objective manner that overcomes many testing problems. Once data has been acquired, a special algorithm is used to determine when brake noise or vibration occurs during a stop event and from which corner of the vehicle it originates. It also records speed, brake line pressures, temperatures on the pads, ambient temperature, and ambient relative humidity, so engineers will know under what operating conditions the brake noise events occurred. The system can be utilized both on vehicles running city traffic tests and on dynamometer applications.