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Multiple field trials and nearly a decade of laboratory studies have demonstrated that shear stable multigrade hydraulic fluids improve fuel economy. These studies have determined that fuel efficiency is dependent upon temperature, fluid viscosity and shear stability. This paper presents a viscosity classification system proposed by the National Fluid Power Association (NFPA) Fluids Technical Committee. This system is analogous to the SAE J300 viscosity classification system for engine oils. The letter “L” is used in place of “W” as the designation for the low temperature grade. Under this new classification system, NFPA 32L-68 fluids will provide the low temperature viscosity properties of an ISO VG 32 hydraulic fluid and the high temperature viscosity properties of an ISO VG 68. In addition, fluids that meet the requirements of the proposed NFPA Energy Efficient classification system increase fuel economy and productivity while reducing CO2 emissions.

Polyurethane (PU) foam is used for many automotive applications with the benefits of being lightweight, durable, and resistant to heat and noise. Applications of PU foams are increasing to include non-traditional purposes targeting consumer comfort. An example of this is the use of PU foam between the engine and engine cover of a vehicle for the purpose of noise abatement. This addition will provide a quieter ride for the consumer, however will have associated environmental impacts. The additional weight will cause an increase in fuel consumption and related emissions. More significant impacts may be realized at the end-of-life stage. Recycling PU foams presents several challenges; a lack of market for the recyclate, contamination of the foams, and lack of accessibility for removal of the material.

A sports car exhibits many challenges from an aerodynamic point of view: drag that limits top speed, lift - or down force - and balance that affects handling, brake cooling and insuring that the heat exchangers have enough air flowing through them under several vehicle speeds and ambient conditions. All of which must be balanced with a sports car styling and esthetic. Since this sports car applies two electric motors to drive front axle and a high-rev V6 turbo charged engine in series with a 9-speed double-clutch transmission and one electric motor to drive rear axle, additional cooling was required, yielding a total of ten air cooled-heat exchangers. It is also a challenge to introduce cooling air into the rear engine room to protect the car under severe thermal conditions. This paper focuses on the cooling and heat resistance concept.

Torque converters are used as coupling devices in automobile powertrains involving automatic transmissions. Efficient modeling of torque converters capturing various modes of operation is important for powertrain design and simulation, (Hroval and Tobler 1, Ishihara and Emori 2) optimization and control applications. Models of torque converters are available in various commercial simulation packages, Hadi et. al. 3. The information about the effect of model parameters on torque converter performance is valuable for any design operation. In this paper, a symbolic sensitivity analysis of a torque converter model will be presented. Direct differentiation (Serban and Freeman 4) is used to generate the sensitivity equations which results in equations in symbolic form. By solving the sensitivity equations, the effect of a perturbation of the model parameters on the behavior of the system is determined.

Off highways vehicles especially tractors are prone to operate on fields where tractors are exposed to dry crops, chaffs (the husks of corn or other seed separated by winnowing or threshing) and particles which can catch fire easily when it is exposed to surface/skin temperature of more than 200 degree Celsius. It will be a basic projection that tractor will be having vertical exhaust tube at a height but there are certain tractors and applications where exhaust pipe must be below certain height, and which will be close to the ground. In these scenarios the skin temperature of exposed exhaust tail pipe part must be within a limit and that must be within the existing design. Break firing point of chaffs and husk also experimented at different moisture level. Several options are being verified on different heat flow and geometry changes, additional air entry jet nozzle with double pipe arrangement.

One of the prominent representatives of heat-resistant polymers was the class of Polyethylene Terephthalate Glycol (PETG) with high-strength, but still lightweight. The carbon fiber with PETG (CFPETG) composites also gives even more resistance to heat and chemical, creating it a demandable choice of application in automotive and other industrial components. This paper aims to study the most significant process parameter of FDM technique for different infill density of 25%, 50%, 75%, and 100% at various sliding load condition and sliding distance on wear and friction characteristics of PETG and CFPETG under annealed condition was investigated via dry sliding tribometer apparatus. The trials were done by applying the load of 10N, 20N, 30N, 40N, with a sliding distance of 1000m, 2000m for the time period of 10 min at room temperature and responses such as wear rate and coefficient of friction were recorded for further analysis.

The advantages of the injection/compression molding process for thermoset composite materials will be addressed as follows: 1) Thermoset composite history and transition of compression molding to injection and injection/compression molding processes. 2) Advantages of automated injection/compression molding to reduce labor, scrap rate and product cost. 3) Machine design requirements for efficient and consistent injection/compression molding. 4) Mold design examples will include moveable core pins to eliminate weld lines, gate-cutters used to balance flow, and other standard injection/compression concepts. 5) Current and future under-hood applications for thermoset composite materials. Design engineers in the automotive industry have been in the forefront of the accelerating movement toward replacing machined and cast metal parts with molded plastic parts.

PC/ABS blends are being used in applications for automotive parts because of their good balance in heat resistance, impact strength, and dimensional stability. The weld line strength of the blends is, however, much inferior to that of each base polymer, and this poor strength sometimes causes trouble in the performace of the final product. A study was made on the composition of PC/ABS blends for improving this poor weld line strength. As the result of this study, it was found that a specific composition of ABS (high molecular weight SAN, higher rubber content, and high molecular weight PC) and an additive (modified polyolefine) could remarkably improve the weld line strength. Electron microscopic photographs and physical properties showed that the specific additive could improve the compatibility of PC and ABS resins. This paper focuses on the conclusion of the development effort of the improved PC/ABS blend.

A metal support has a potential to improve an engine output and the conversion efficiency. In order to satisfy both requirements, the back pressure drop should be reduced and the high-temperature use of the catalyst converter has to be a must. To develop such a metal support, a manifold converter without a retainer is the best choice. Removing a retainer resulted in joining the metal honeycomb-core to the jacket. Brazing was selected. Installing as a manifold converter led a metal support to the severe environment in which the high mechanical durability was required. The back pressure drop, the adhesion of the washcoat and the conversion performance have been investigated for the high-temperature use. To develop the brazed structure to meet the high mechanical durability, analyzing the temperature distribution and the fracture modes in a metal support has been conducted through the endurance engine-bench test.

A newly developed viscous-rubber damper, which employed an innovative structure and a new heat resistant rubber, solved some tough problems. This paper dealt more closely with the features of the new viscous-rubber damper and the new calculation method for the viscous-rubber damper. This damper has been employed for Hino new K13C (K-II) higher boost turbocharged and air to air charge-cooled diesel engine, which has extreme severity on the torsional vibration.

In response to the growing industry interest in environmentally acceptable (EA) lubricants, a hydraulic oil development program was initiated with these express objectives: Define the environmental impact and performance expectations for a lubricant used in applications where inadvertent leakage to the environment may occur. Develop a new product which degrades rapidly and is nontoxic to fish while providing satisfactory field performance in severe applications. This paper will first review the current regulatory initiatives and proposed ecotox test requirements for this class of lubricant. In addition, ecotox data for the candidate fluids will be presented along with recommendations aimed at more clearly defining the test requirements and limits. Lubricant performance data, including laboratory evaluation and field experience, for a vegetable-based hydraulic fluid will be presented, identifying both performance strengths and weaknesses.

There are several advantages in using plastic optical fiber in automobiles. Plastic optical fiber for automotive applications can be classified according to two types of applications: those for the passenger compartment and those for the engine room. The two types can be distinguished by their heat resistance and transmission loss properties. The two types of fiber should be installed in places where they would be suitable. In the passenger compartment, a 85°C to 105°C PMMA optical fiber should be used. In the engine room, fiber made of heat-resistant material such as polycarbonate would be ssstable. This paper will describe the properties of optical fibers which can be supplied commercially. It will also describe the properties of optical couplers made through photolithography. In order to incorporate LAN into automobiles, optical components, such as optical couplers, are becoming applicable.

In February of 1987, Dresser introduced a pair of new mechanical drive, off-highway trucks designed to operate in the 35 to 60 ton, rear-dump, classes. These trucks, designated 140M and 210M, replaced three previous models while covering the same payload range. One distinctive feature of these new vehicles was their hydraulic system and in particular the brake control portion of this system. This new hydraulic brake control system can be described as a closed-center arrangement using a pressure-compensated, variable displacement pump as an energy source with accumulator-based energy reserves for independent and redundant circuits. In the basic version, a pair of pressure regulating valves are used to control system pressure at the brakes. These valves can be actuated in tandem by a treadle (foot pedal) or separately by hydraulic pilot pressure. A single, filtered hydraulic fluid is used throughout the system and is stored in a single reservoir vented to atmosphere.

Effects of thermal cycle and irradiation on mechanical proreties of Carbon Fiber Reinforced Plastic (CFRP) and adhesives were experimentally investigated. The IM-6/6376, toughened epoxy composite and T800/PMR-15, heat-resistant polyimide composite, and typical nine types of epoxy adhesives were selected as candidate sturctural materials for the future space applications. These materials were subjected to up to 10 MGy irradiation and/or 3000 thermal cycle (-100 °C to 100 °C) which simulates the space environment. After these conditionings, specimens were mechanicaly tested over the temperature range of -100 °C to 100 °C. The results were that the IM-6/6376 was not affected by irradiation and/or thermal cycle. this material showed essentially good overall durability performance in space environments. T-800/PMR-15 was not affected by irradiation this material showed good durability against radiation. The other hands, the adhesives was greatly affected by irradiation and/or thermal cycle.

Hoses and assembies used in hydraulic applications are constantly being required to do more and more. The hydrostatic drives are becoming more sensitive to dirt and contamination. In addition, new hydraulic fluids are now being introduced that are more environmentally, safe. As a result, care must be taken in choosing the materials used and the processes of manufacturing in order to ensure that the assemblies provide long life and will not contribute to system failures.

The full potential of active suspension has not yet been realized because of the limitations of available actuators. Current active suspension systems use hydraulic rams with the flow of hydraulic fluid to the ram controlled by a servo-valve to exert the desired force. The objective of this paper is to describe an alternate arrangement of hydraulic actuator which combines great compliance with short reaction times. The heart of the arrangement is a set of hydraulic rams which are connected between the body of the vehicle and one wheel assembly. Each of the rams is connected via a separate three-way, two-position valve to an accumulator, kept at a constant pressure, or a reservoir depending on the position of its valve. The force exerted by the actuator depends on the piston areas of those rams connected to the accumulator.

An understanding of the nature of heat resistant expanded bead foam is necessary for designing instrument panel components using this material. This paper will focus on properties and design parameters of foam molded from high heat expanded styrene maleic anhydride copolymer.

A two-coat system has been developed showing some potential for application over engine component parts. This system consists of a non-chromate epoxy primer and an aluminized epoxy topcoat. Results of tests conducted show that this combination not only offers excellent corrosion, chemical and heat resistance but also excellent adhesion over aluminum and magnesium alloys. These two alloys are widely used as component parts of engines.

Like all industries, the fluid power industry is under increasing pressure to identify and use hydraulic fluids that offer higher performance, improved fire safety, and exhibit improved environmental and toxicological behavior. Recently a novel hydrolube composition has been developed that is capable of being used in hydraulic pumps at pressures of 34.4 MPa (5000 psi) and greater*. In addition to being a Group 1 Fire Resistant Hydraulic Fluid according to the new Factory Mutual Research Corporation's testing methodology, this high-performance hydrolube also exhibits excellent biodegradability and toxicology properties. The objective of this paper is to discuss pump performance, fire resistance, and environmental and toxicology properties of this fluid..

Electric power steering is a technology that will define the future. It eliminates the need for a power steering pump, hoses, hydraulic fluids, and a drive belt and pulley on the engine. As a result, electric power steering is energy efficient and environmentally compatible - while offering extras like simplified tuning, packaging flexibility and engine-off steering assist. With superior performance, electric power steering will be the technology that challenges the familiar, 50-year-old concepts of hydraulics.