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1 One issue raised by the use of austenitic stainless steels in commercial vehicles is the increase in material costs. To reduce those material costs, a nitric acid electropolishing treatment was applied to SUS436L (18 Cr - 1.5 Mo - 0.4 Nb) and corrosion tests were conducted to compare its corrosion resistance to that of SUS316L(16 Cr - 12 Ni - 2 Mo). Compared to SUS316L, SUS436L subjected to nitric acid electropolishing indicated superior corrosion resistance. In addition, XPS and TEM analyses showed that while the SUS436L passivation film layer contained approximately twice as much chromium, its thickness was also generally reduced by approximately half, to 2 nm. These results suggest that electropolishing with nitric acid, which is highly oxidative, formed a fine passivation film.

Research activities in the development of reliable computational models for aftertreatment systems are constantly increasing in the automotive field. These investigations are essential in order to get a complete understanding of the main catalytic processes which clearly have a great impact on tailpipe emissions. In this work, a 1D chemical reaction model to simulate the catalytic activity of a Pd/Rh Three-Way Catalyst (TWC) for a Natural Gas heavy-duty engine is presented. An extensive database of tests carried out with the use of a Synthetic Gas Bench (SGB) has been collected to investigate the methane abatement pathways, linked to the lambda variation and oxide formation on palladium surface. Specific steady-state tests have shown a dynamics of the methane conversion even at fixed λ and temperature conditions, essentially due to the Pd/PdO ratio.

This SAE Standard provides a comprehensive list of requirements for the selection, identification, and control of metric and inch sized fasteners for use in shipboard applications for both shipbuilder installed joints and for use in shipboard components. The fastener selection requirements include the following: a Materials b Thread selection c Plating, coatings, and surface treatments d Locking devices and elements e Screw thread fastener inserts f Fastener part or identifying numbers g Identification markings

This Hydrospace Information Report (HIR) identifies the general environmental considerations for the design, development, evaluation, and testing of advanced surface craft, submersible vehicles, and other marine craft. This HIR provides criteria on the environmental limits within which marine vehicles, related components, and associated equipment should operate satisfactorily and reliably. This HIR is intended for use as a guide for the development of specific environmental requirements to be included in detailed specifications for marine vehicles and associated equipment. Specific requirements are in a state of continual change as our knowledge of the ocean environment increases. The ocean environment varies with location and time. Changes in the ocean environment can occur not only on a seasonal basis but also monthly, weekly, daily, and in some cases even hourly.

This Hydrospace Information Report (HIR) identifies the general environmental considerations for the design, development, evaluation, and testing of advanced surface craft, submersible vehicles, and other marine craft. This HIR provides criteria on the environmental limits within which marine vehicles, related components, and associated equipment should operate satisfactorily and reliably.

A number of oxidation catalysts have been prepared using different types of advanced support materials such as ceria-zirconia, silica-titania, spinels and perovskites. Active metals such as Pd and Au-Pd were loaded by conventional impregnation techniques and/or deposition-precipitation methods. A liquid hydrocarbon delivery system was designed and implemented for the catalyst test benches in order to simulate the diesel engine exhaust environment. The activity of fresh (no degreening) catalysts was evaluated with traditional CO and light hydrocarbons (C2H4, C3H6) as well as with heavy hydrocarbons such as C10 H22.

Durability and reliability performance is one of the most important concerns of a recently developed Thermal Regeneration Unit for Exhaust (T.R.U.E-Clean®) for exhaust emission control. Like other ground vehicle systems, the T.R.U.E-Clean® system experiences cyclic loadings due to road vibrations leading to fatigue failure over time. Creep and oxidation cause damage at high temperature conditions which further shortens the life of the system and makes fatigue life assessment even more complex. Great efforts have been made to develop the ability to accurately and quickly assess the durability/reliability of the system in the early development stage. However, reliable and validated simplified engineering methods with rigorous mathematical and physical bases are still urgently needed to accurately manage the margin of safety and decrease the cost, whereas iterative testing is expensive and time consuming.

Fatigue, creep, oxidation, or their combinations have long been recognized as the principal failure mechanisms in many high-temperature applications such as exhaust manifolds and thermal regeneration units used in commercial vehicle aftertreatment systems. Depending on the specific materials, loading, and temperature levels, the role of each damage mechanism may change significantly, ranging from independent development to competing and combined creep-fatigue, fatigue-oxidation, creep-fatigue-oxidation. Several multiple failure mechanisms based material damage models have been developed, and products to resist these failure mechanisms have been designed and produced. However, one of the key challenges posed to design engineers is to find a way to accelerate the durability and reliability tests of auto exhaust in component and system levels and to validate the product design within development cycle to satisfy customer and market's requirements.

With the increasing need for developing fuel-efficient and high-performance vehicles, light weighting has become a very important aspect in automotive industry. Hence conversion of the existing metal components to composites is gaining momentum. Composite materials are much lighter than metals and offer many advantages such as fuel efficiency, corrosion resistance and improved life which has resulted in the increased usage of composite materials. Front under-run protection device (FUPD) is a protective device which is fitted on the front side of a truck which prevents the vehicle in front from under-running below the truck and also absorbs impact energy in case of a collision. This paper discusses the design, development and certification from ARAI of the lightweight composite front under-run protection device (FUPD). It has resulted in 33.33% weight reduction compared to the earlier metal component.

For renewable fuels to displace petroleum, they must be compatible with emissions control devices. Pure biodiesel contains up to 5 ppm Na + K and 5 ppm Ca + Mg metals, which have the potential to degrade diesel emissions control systems. This study aims to address these concerns, identify deactivation mechanisms, and determine if a lower limit is needed. Accelerated aging of a production exhaust system was conducted on an engine test stand over 1001 h using 20% biodiesel blended into ultra-low sulfur diesel (B20) doped with 14 ppm Na. This Na level is equivalent to exposure to Na at the uppermost expected B100 value in a B20 blend for the system full-useful life. During the study, NOx emissions exceeded the engine certification limit of 0.33 g/bhp-hr before the 435,000-mile requirement.

Abstract Late-cycle soot oxidation in heavy-duty (HD) diesel engine low-swirl combustion was investigated using single-cylinder engine and spray chamber experiments together with engine combustion simulations. The in-cylinder flow during interactions between adjacent flames (flame-flame events) was shown to have a large impact on late-cycle combustion. To modify the flame-flame flow, a new piston bowl shape with a protrusion (wave) was designed to guide the near-wall flow. This design significantly reduced soot emissions and increased engine thermodynamic efficiency. The wave’s main effect was to enhance late-cycle mixing, as demonstrated by an increase in the apparent rate of heat release after the termination of fuel injection. Combustion simulations showed that the increased mixing is driven by enhanced flow re-circulation, which produces a radial mixing zone (RMZ).

This SAE standard covers minimum requirements for two types of metallic tubing and pipe as used in automotive air brake systems. It includes material and performance specifications, corrosion precautions, and installation recommendations. Copper tubing is designated Type 1, and galvanized steel pipe Type 2.

The scope of this Recommended Practice is to delineate groups of materials for which there is considerable fabrication and operating experience in the sea water environment. In addition, some of the more promising materials for possible future applications are covered.

The scope of this Recommended Practice is to delineate groups of materials for which there is considerable fabrication and operating experience in the sea water environment. In addition, some of the more promising materials for possible future applications are covered.

This SAE Part Standard covers selected machine screws manufactured in accordance with American Society for Mechanical Engineers dimensional standards. This SAE standard covers material most often used in ship systems and equipment but its use may be applied wherever fasteners of the covered materials are used. This document permits the fasteners to be identified and ordered by a part or identifying number (PIN) as defined in this document.

The effect of a novel particle oxidation catalyst (POC®) on diesel particle emissions is studied in heavy duty and light duty applications. Regulated particulate matter (PM) emission measurement is followed by analyzing either soluble organic fraction (SOF) or volatile organic (VOF) fraction. In addition, in heavy duty diesel application, size distributions are measured. Results show that PM reductions as high as 48-79% can be achieved when using POC in combination with a conventional diesel oxidation catalyst (DOC). As expected, the volatile fraction of the PM was very effectively reduced, but also the non-volatile fraction (i.e. soot) was reduced. In tested steady state driving modes soot reduction was found to be 31-55%.

Environmentally acceptable hydraulic fluids are increasingly specified for use in hydraulic equipment working in environmentally sensitive areas. This paper describes the research methodology that was used to develop a high performance synthetic, environmentally acceptable hydraulic fluid. Product development consisted of: (1) setting the standards for environmental acceptability, (2) screening base fluids and additives for technical performance and minimal impact on the environment, (3) designing a formulation to meet these targets and (4) field experience. Test results demonstrating the high performance and low environmental impact of the new fluid are discussed. A key challenge when formulating an environmentally acceptable hydraulic fluid is to achieve satisfactory oxidation stability. The absence of a suitable oxidation stability test, which can differentiate between environmentally acceptable fluids and correlate with field performance, has been an issue for several years.

Natural synthetic esters are nowadays often applied as lubricants for their advantageous characteristics such as good biodegradability, low toxicity and the fact that they enable safe operation under very low and high temperatures. There is a wide range of applications in which the natural synthetic esters are used for their good biodegradability characteristics. Currently, a number of investigations are done towards oxidation stability of the natural synthetic esters. The methods of assessing the oxidation stability, benchmarking results and the outcome of a study on the effect of anti-oxidants in natural synthetic esters are decribed.

The use of environmental friendly lubricants is driven by the emergence of regulations appearing in many countries. The absence of water toxicity is of prime importance. To meet the stringent toxicity requirements, it is important to minimize the amount of additives which are potentially toxic. Base stocks of stable fatty chemicals were selected because the inherent properties closely matched the fluid properties required. This would necessitate the use of a minimum amount of additives. Particular attention has been devoted to the following : low temperature stability, proper viscosity, elastomers swelling, resistance to oxidation and parking brake friction. Complex neopolyol esters based on blends of linear saturated fatty acids are good candidates since they closely match the requirements of hydraulic fluids meeting the ecolabel specification. Comparisons with unsaturated derivatives and synthetic petrochemical esters base oils show their advantages.

“Bio Fluids” have the remarkable property of rapidly degrading in natural environments. Unfortunately, the same fluid chemistry leading to biodegradation also leads to fluid instability in machine environments. This dilemma can be resolved through vigilant contamination control. Maintaining biodegradable fluids at extremely low levels of particulate contamination and extremely low levels of moisture discourages fluid deterioration, especially the breakdown mechanisms of oxidation and hydrolysis. Maintaining fluids clean and dry also achieves the additional benefits of limiting the wear and corrosion of mechanical components. The challenge is to control these contaminants in the fluid systems of heavy machinery operating in wet and dusty environments.