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For the production of deep-drawn parts on single-acting presses, constructive tool variants are presented, by means of which the drawing result may be improved and the machine-related disadvantages may be compensated. For the new tool principle with a “locked tool”, connectable adjustment elements produce a direct form closure connection between the drawing die and the blank-holder, thus replacing the function of the die cushion. Due to an active control of the blank-holding force, these so-called Damping-Locking elements make it possible to directly influence the deep-drawing process. By means of the hydraulic drawing cylinders, the blank-holding force may, locally along the perimeter of the part and during the drawing process, be adapted to the process conditions required. The elastic blank-holder automatically adapts itself to the sheet thickness of the flange.

In temperate climatic conditions the water depths on wet roads are generally low, typically less than 1 mm. In this paper we examine the various types of road surface and the manner in which they can be classified in terms of macro and micro-texture. We propose a simplified representation of the tyre road interface in which the tyre footprint is divided into two zones, a dry zone in which dry road friction levels are obtained and an initial wet zone in which there is a water layer between the tyre and road and which gives no retardation. A generalised relation for the variation in the size of the wet zone with speed is proposed. The model is applied to published data for road surfaces of differing characteristics with fully treaded and smooth tyres. The model is shown to give a good representation of the variation in locked wheel retardation with speed and highlights the sensitivity of stopping distance to variations in road surface and tyre tread depth.

The Lockheed Martin Low-Speed Wind Tunnel (LSWT) is a closed-return wind tunnel with two solid-wall test sections. This facility originally entered into service in 1967 for aerodynamic research of aircraft in low-speed and vertical/short take-off and landing (V/STOL) flight. Since this time, the client base has evolved to include a significant level of automotive aerodynamic testing, and the needs of the automotive clientele have progressed to include acoustic testing capability. The LSWT was therefore acoustically upgraded in 2016 to reduce background noise levels and to minimize acoustic reflections within the low-speed test section (LSTS). The acoustic upgrade involved detailed analysis, design, specification, and installation of acoustically treated wall surfaces and turning vanes in the circuit as well as low self-noise acoustic wall and ceiling treatment in the solid-wall LSTS.

A brief description of the Lockheed-Georgia Co.’s low speed wind tunnel includes discussions of facility characteristics, such as the test section sizes, speed ranges, read-out system capability, balance system limits, and instrumentation hookup capability and versatility. Accessory equipment is also described as it can support wind tunnel testing of automotive vehicles.

This paper is concerned with the use of solid elements in sheet metal forming simulation, particularly springback prediction for flanging when the flanging radii are comparable with the metal thickness. It is demonstrated that appropriate solid elements must be used instead of shell elements in order to obtain adequate results. Numerical difficulties associated with development of suitable solid elements are discussed in detail, with emphasis on the volumetric locking and transverse shear locking phenomena respectively. The transverse shear locking arises from the incompatible deformation modes when the element is used for thin structure bending analysis. A four point bending testing problem is used to study the performances of different solid elements. A locking-free solid element based on assumed strain formulation is developed in Ford in-house program MTLFRM for accurate springback prediction, and a flanging example is given to demonstrate its application.

The objective of this project was to assess the effects of various blends of biodiesel on locomotive engine exhaust emissions. Systematic, credible, and carefully designed and executed locomotive fuel effect studies produce statistically significant conclusions are very scarce, and only cover a very limited number of locomotive models. Most locomotive biodiesel work has been limited to cursory demonstration programs. Of primary concern to railroads and regulators is understanding any exhaust emission associated with biodiesel use, especially NOX emissions. In this study, emissions tests were conducted on two locomotive models, a Tier 2 EMD SD70ACe and a Tier 1+ GE Dash9-44CW with two baseline fuels, conventional EPA ASTM No. 2-D S15 (commonly referred to as ultra-low sulfur diesel - ULSD) certification diesel fuel, and commercially available California Air Resource Board (CARB) ULSD fuel.

THE inherent simplicity of the gas turbine and its well-known success in aircraft applications is leading to its consideration for locomotive use. As a matter of fact, gas turbine locomotives have already found limited use by a few railroads throughout the world. The author discusses these applications and some of the lessons learned from them. He points out that, although the first gas turbine locomotive to be put in service was built in 1941 - the same year that the first commercial diesel locomotive was placed in service -the latter has forged rapidly ahead, so that today the railroads are about 75% dieselized. What, then, has held the gas turbine locomotive back? Mr. McGee points out that two of the most significant factors responsible are: 1. Metallurgical problems - the need for materials capable of withstanding the high temperatures encountered. 2. High fuel consumption.

The use of the radioactive ring technique to study variables affecting railroad diesel engine wear was first reported by the Southern Pacific Transportation Company and Standard Oil Company of California in 1961. Researchers from the same companies undertook new investigations in 1969 and 1970 using a current generation turbocharged locomotive. As in the previous program, operation was carried out in a stationary installation with the power generated absorbed by auxiliary air-cooled grids. New testing procedures and counting equipment were employed. Radioactive chromium was counted simultaneously with the measurement of irradiated iron particles in the oil. New and used lubricants with variations in alkalinity value were evaluated using distillate fuels with sulfur contents ranging from 0-1%. Two ring metallurgy combinations were evaluated.

With increased complexity of new equipment, introduced to the west coast logging industry, it has become necessary to reevaluate machinery control techniques. Proper coordination of clutch and brake application is very critical. The old methods of control are not adequate. Through the use of carefully designed logic systems, maintenance-free programmed controls may be produced to completely regulate all operating characteristics of the machines The operator will need little training. His work will be simplified and he will be required to make fewer decisions.

With the arrival of Industry 4.0 era, traditional manufacturing industries will convert to intelligent systems. In addition to the computerization of manufacturing systems, logistics system will require automatic and IT-controlled processes integrated with Industry 4.0. This paper presents an analysis of the scope, hierarchy, and principles of logistics planning with emphasis on the concepts required to achieve intelligent logistic system. Integrated logistics system will directly connect and manage the entire distribution chain visually from the material source to the end customer upwards and at the same time, connect to the warehouse of suppliers downwards. The logistics planning processes can be optimized by setting up mathematical models and logical relationship with virtual simulation and verification tools. Relying on big data and cloud computing for sales forecasts permits better adjustment of inventory levels across the entire supply chain.

Modern military ground vehicles are dependent not only on armor and munitions, but also on their electronic equipment. Advances in battlefield sensing, targeting, and communications devices have resulted in military vehicles with a wide array of electrical and electronic loads requiring power. These vehicles are typically designed to supply this power via a main internal combustion engine outfitted with a generator. Batteries are also incorporated to allow power to be supplied for a limited time when the engine is off. It is desirable to use a subset of the battlefield electronics in the vehicle while the engine is off, in a mode called “silent watch.” Operating time in this mode is limited, however, by battery capacity unless an auxiliary power unit (APU) is used or the main engines are restarted.

Zinc dialkylphosphate (ZP), a sulfur free analogue of Zinc dialkyldithiophosphate (ZDTP) has been synthesized and tested for engine oil application. The sulfur free engine oil based on ZP showed excellent TBN retention and engine cleanliness in several engine tests which were operated at low and high temperatures. A prototype low phosphorus (0.05%) and low sulfated ash (0.5%) engine oil exhibited even better longer drain performance than a fully synthetic engine oil containing 0.1% P and 1.1% sulfated ash. Thus, zinc dialkylphosphate can be a promising candidate as a ZDTP substitute for future catalyst system compatible engine oil.

Due to their excellent mechanical properties, glass fiber reinforced plastics are currently used in many applications. In polyurethanes, these fiber reinforced parts have been traditionally manufactured by RRIM, glass fiber mixed into the polyol, and by SRIM, glass mat placed in the tool and polyurethane is then poured or injected onto the mat. These processes are plagued with several manufacturing steps that are undesirable; such as handling glass fiber, trimming glass mat prior to molding, punching and trimming large holes in the finished part which wastes materials and time, manual handling of the mats or mold parts several times in the process, etc. Prompted by industry's wish to produce these articles more efficiently and cost-effectively, and to be able to employ long fibers Krauss-Maffei developed the Long Fiber Injection Process, named LFI. This revolutionary process introduces long fibers directly at the mixhead.

Since the introduction of injection moldable Long Fiber Reinforced Thermoplastic (LFRT) composites, continued improvements in both manufacturing technology and processing methods, mechanical performance has dramatically improved. Notably, the step increase in multi- axial impact has significantly differentiated these long glass fiber composites from short glass fiber materials and can place the impact performance commensurate with glass mat thermoplastics (GMTs). This paper will focus on the improvements in mechanical performance of polypropylene, polyamide, and polyphthalamide long glass fiber systems. Specific processing parameters as well as improved screw and tool designs have contributed and will be reviewed. These thermoplastic composites fit many processing modes in addition to injection molding.

Two models are presented for the long life (107 cycles) axial fatigue strength of four ferrous powder metal (PM) material series: sintered and heat-treated iron-carbon steel, iron-copper and copper steel, iron-nickel and nickel steel, and pre-alloyed steel. The materials are defined at ranges of carbon content and densities using the broad data available in the Metal Powder Industries Federation (MPIF) Standard 35 for PM structural parts. The first model evaluates 107 cycles axial fatigue strength as a function of ultimate strength and the second model as a function of hardness. For all 118 studied materials, both models are found to have a good correlation between calculated and 107 cycles axial fatigue strength with a high Pearson correlation coefficient of 0.97. The article provides details on the model development and the reasoning for selecting the ultimate strength and hardness as the best predictors for 107 cycles axial fatigue strength.

This paper investigates and describes the fatigue mechanism in bearings for automotive alternators. We have analyzed the peculiar microstructure change found in these bearings. We have also investigated the effects of grease properties, vibration, and elastic deformation of the outer ring. By analyzing the bearings used in actual engine tests and grease tests for fundamental characteristics, we were able to conclude that the fatigue causes were two-fold: load amplification caused by resonance and high bending stresses caused by elastic deformation of the outer ring. As a practical result, we were able to adopt a newly formulated grease which decreased the vibration level and the peak rolling element load. This led to the development of longer life bearings for automotive alternators.

Natural gas burning engines, both large and small, are being applied to an increasing number of installations where operating cost considerations show an advantage over purchased electric power. Air conditioning and refrigeration applications account for a large percentage of these installations. This paper reviews the consideration given to the development and application of a series of engines intended specifically for this type of service. The overall objective has been to reduce the cost of power by providing efficient operation, long service life, and unattended operation which fits the maintenance pattern of the other equipment in the installation.