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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.

Fuel economy, Emission regulation and extended oil drain intervals (ODI) are the three key driving forces for engine oil development. More and more attentions have been focused on long ODI diesel engine oil both from the domestic OEMs and oil suppliers, and the ODI was being periodically improved from a normal mileage of about 1×104 kilometers to 6/8/10×104 km or even 12×104 km just within several years on China market. Lots and lots of factors may affect the oil life including oil properties, engine technologies, after-treatment devices and engine working conditions and so on. While from the oil side, the main factors contribute to the oil drain intervals may be the oil nitration and oxidation, soot contamination, base number deterioration and sludge accumulation and etc. There are two strategies to extend the oil longevity applied currently.

An inhibitor package which is silicate-, nitrate-, borate- and phosphate-free has been developed as the basis for a world-wide automotive coolant formulation. The formulation contains aliphatic mono- and dicarboxylic acids and tolyltriazole as the sole inhibitors. Formulations containing carboxylic acid inhibitors have been studied in ASTM bench tests and found to sufficiently protect all prevalent cooling system metals. In addition, fleet tests have shown that carboxylic acid inhibitors deplete much more slowly than conventional inhibitors, making possible a much longer life coolant. Results from laboratory tests which simulate extended usage indicated that carboxylic acid-containing coolants have a significantly longer life span for the protection of all cooling system metals. Finally, the carboxylic acid/tolyltriazole inhibitor package is completely adaptable to a propylene glycol base.

Recently various kinds of position sensors have been used in automotive subsystems which include Electronic Fuel Injection, Active Suspension and Exhaust Gas Recirculation (EGR). Because a potentiometer has a simple structure in which a brush slides on a resistor surface, it has many advantages such as high temperature applications, low cost, high signal level and almost infinite resolution compared to other kinds of position sensors that are magnetic or optical in nature. The potentiometer is considered to have the highest potential for a position sensor. However, conventional potentiometers sometimes lose their linearity after use under severe conditions such as engine vibration (dither). They can endure only tens of millions of cycles of dither.

This paper summarizes a technology roadmap for completing advanced development of a Proton Exchange Membrane (PEM) Regenerative Fuel Cell (RFC) to meet long life (20,000 hrs at 50% duty cycle) mobile or portable power system applications on the surface of the Moon and Mars. Development of two different sized RFC power system modules is included in this plan (3 and 7.5 kWe). A conservative approach was taken which includes the development of a Ground Engineering System (GES), Qualification Unit (QU), and Flight Unit (FU). Development of a long life system was estimated to require about 7 years (through flight qualification). This development plan was formulated as part of a NASA Lewis task order contract (NAS3-25808) entitled “Mars Power System Concept Definition.” This paper includes a concept description, technology assessment, development issues, development tasks, and development schedule.

This paper shows that the analysis of factors such as costs, weights, fuel distribution logistics, etc. indicates that the replacement of internal combustion engines (ICE) by fuel cell/electric motor (FC/EM) systems, can be more attractive to aeronautical than to automotive applications. For long range airplanes especially, where the fuel represents an important fraction of the vehicle weight, the penalties from that replacement by a heavier system, can be overcome by the fuel weight reductions resulting from the higher fuel cell efficiencies. The necessity of FC/EM powered airplanes is also discussed in view of the eventual climate effects the air traffic may have, due to the injection of carbon dioxide and water vapor into the high troposphere.

A study is made of U.S. and worldwide aluminum supply/demand and issues which led to shortages of the recent past. Key economic factors and their impact on future availability of aluminum are discussed by constructing possible scenarios.

An analysis was made to determine which potential highway and motor vehicle safety activies were most deserving of further pursuit so as to obtain the greatest improvement in safety at the least cost. Criteria were established to guide in the rating and ranking of potential safety projects. The most significant national safety problems were identified and a description and schedule of the chosen safety projects to address those problems were prepared.