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Cast iron is generally thought of as a weak, dirty, cheap, brittle material that does not have a place in applications requiring high strength and defined engineering properties. While gray cast iron is relatively brittle by comparison with steel, ductile iron is not. In fact, ductile iron has strengths and toughness very similar to steel and the machinability advantages make an attractive opportunity for significant cost reductions. Gray and ductile iron bar stock is commercially available and can be used as a direct replacement in applications that are currently being made from carbon steel bar. Ductile iron bar stock conversions are very prevalent in many fluid power applications including glands and rod guides, cylinders, hydrostatic transmission barrels and in high-pressure manifolds. Automotive gears are being converted to ductile iron for its damping capacity and cost reductions.

Wear characteristics of four bearing materials have been investigated under different sliding conditions. The bearing materials used were CDA 954, CDA 863, CDA 932, and CDA 938. Using a Taber Wear Tester, a cylinder on a flat geometry was used as a tribo contact pair. All bearing materials in the form of a thick cylindrical disk were subjected to combined sliding-rolling motion against a rotating flat disk. The flat disk was either an abrasive disk, or a very soft steel disk, or a hardened steel disk with and without lubrication. Wear was measured as weight loss after several thousand cycles of rotation. Maximum wear of the bearing materials occurred when the counter body was a very soft steel disk. These results together with the wear rate of each bearing material sliding against four different counter bodies are presented. These results are found to be of practical importance in the design and application of journal bearings made of materials used in this investigation.

This standard specifies a procedure for approximating the volume of materials contained in the grapple of bucket linkage operated grapples mounted to excavators. The volume ratings are based on the inside dimensions of the grapple and representative volumes extending beyond the grapple. The method employs the technique of dividing the complex shape of the material in the grapple into simple geometric forms to allow volume calculations of different grapple configurations. The rating method is intended to provide a consistent means of comparing grapple capacities. It is not intended to define actual capacities that might be observed in any specific application.

Cylinder pressure-based combustion control is widely introduced for passenger cars. Benefits include enhanced emission robustness to fuel quality variation, reduced fuel consumption due to more accurate (multi-pulse) fuel injection, and minimized after treatment size. In addition, it enables the introduction of advanced, high-efficient combustion concepts. The application in truck engines is foreseen, but challenges need to be overcome related to durability, increased system costs, and impact on the cylinder head. In this paper, a new single cylinder pressure sensor concept for heavy-duty Diesel engines is presented. Compared to previous studies, this work focuses on heavy-duty Diesel powertrains, which are characterized by a relatively flexible crank shaft in contrast to the existing passenger car applications.

The solution to the problem of establishing the value of the maximum stress in a uniform cylinder with fixed ends, subjected to a unit step change in pressure is presented. It is shown that the ratio of the maximum transient stress to the steady-state stress is a monotonically decreasing function of the damping ratio of the shell. The stress ratio approaches a value of 2 as the damping ratio and the parameter ψ, defined as

The SAE J1939 communications network is developed for use in heavy-duty environments and suitable for horizontally integrated vehicle industries. The SAE J1939 communications network is applicable for light-duty, medium-duty, and heavy- duty vehicles used on-road or off-road, and for appropriate stationary applications which use vehicle derived components (e.g., generator sets). Vehicles of interest include, but are not limited to, on-highway and off-highway trucks and their trailers, construction equipment, and agricultural equipment and implements. SAE J1939-71 Vehicle Application Layer is the SAE J1939 reference document for the conventions and notations that specify parameter placement in PGN data fields, the conventions for ASCII parameters, and conventions for PGN transmission rates. This document previously contained the majority of the SAE J1939 data parameters and messages for information exchange between the ECU applications connected to the SAE J1939 communications network.

The SAE J1939 communications network is developed for use in heavy-duty environments and suitable for horizontally integrated vehicle industries. The SAE J1939 communications network is applicable for light-duty, medium-duty, and heavy-duty vehicles used on-road or off-road, and for appropriate stationary applications which use vehicle derived components (e.g., generator sets). Vehicles of interest include, but are not limited to, on-highway and off-highway trucks and their trailers, construction equipment, and agricultural equipment and implements. SAE J1939-71 is the SAE J1939 reference document for the conventions and notations used to specify the parameter (SP) placement in PG data, the conventions for ASCII parameters, and conventions for PG transmission rates. This document previously contained the majority of the SAE J1939 OSI application layer data parameters and messages for information exchange between the ECU applications connected to the SAE J1939 communications network.

A variable swirl inlet system with swirl control subport was developed with consideration of how to control the angular momentum of inlet flow into the cylinder. The effects of swirl on direct injection diesel engine performance and emissions are investigated with this variable swirl system. Basically, lower swirl level reduces the amount of initial stage burning, which is related to NOx emission, maximum cylinder pressure and rate of cylinder pressure rise, over the entire range of engine speed and load. As a result, in high speed range or partial load range, low swirl level simultaneously gives better BSFC and lower NOx level. An intercooled turbocharged engine with this variable swirl inlet system gave higher low-speed torque, higher brake horse power and better cold startability by selection of optimum swirl level for each engine condition.

This paper traces the historical development of the BICERI variable compression ratio piston and its use in a number of engines. In early petrol experiments a variable compression piston covering the range from 6.5:1 to 16.5:1 showed significant efficiency improvements on 70 octane petrol. In the diesel engine field, Teledyne Continental increased the power of a V12 direct injection tank engine from 550 hp (30 hp per litre) to 1475hp (80 hp per litre) retaining the original crankcase and structure. At BICERI the output of a supercharged research engine was increased to 40 bar bmep with a peak cylinder pressure of only 165 bar. Military application lapsed with the preference for gas turbine engines, but the time is now right to explore the capabilities of variable compression within the wider automotive scene. Volkswagen have been working on a variable compression engine and have shown fuel consumption improvements up to 13% together with lower emissions.

The paper presents the development of a novel approach to the solution of detailed chemistry in internal combustion engine simulations, which relies on the analytical computation of the ordinary differential equations (ODE) system Jacobian matrix in sparse form. Arbitrary reaction behaviors in either Arrhenius, third-body or fall-off formulations can be considered, and thermodynamic gas-phase mixture properties are evaluated according to the well-established 7-coefficient JANAF polynomial form. The current work presents a full validation of the new chemistry solver when coupled to the KIVA-4 code, through modeling of a single cylinder Caterpillar 3401 heavy-duty engine, running in two-stage combustion mode.

Reactivity Controlled Compression Ignition (RCCI) natural gas/diesel dual-fuel combustion has been shown to achieve high thermal efficiency with low NOX and PM emissions, but has traditionally been limited to low to medium loads. High BMEP operation typically requires high substitution rates (i.e., >90% NG), which can lead to high cylinder pressure, pressure rise rates, knock, and combustion loss. In previous studies, compression ratio was decreased to achieve higher load operation, but thermal efficiency was sacrificed. For this study, a multi-cylinder heavy-duty engine that has been modified for dual-fuel operation (diesel direct-injection and natural gas (NG) fumigated into the intake stream) was used to explore RCCI and other dual-fuel combustion modes at high compression ratio, while maintaining stock lug curve capability (i.e., extending dual-fuel operation to high loads where conventional diesel combustion traditionally had to be used).

An accurate air flow rate model is critical for high-quality air-fuel ratio control in Spark-Ignition engines using a Three-Way-Catalyst. Emerging Variable Valve Timing technology complicates cylinder air charge estimation by increasing the number of independent variables. In our previous study (SAE 2004-01-3054), an Artificial Neural Network (ANN) has been used successfully to represent the air flow rate as a function of four independent variables: intake camshaft position, exhaust camshaft position, engine speed and intake manifold pressure. However, in more general terms the air flow rate also depends on ambient temperature and pressure, the latter being largely a function of altitude. With arbitrary cam phasing combinations, the ambient pressure effects in particular can be very complex. In this study, we propose using a separate neural network to compensate the effects of altitude on the air flow rate.

The compression, combustion, and expansion portions of a two-stroke cycle, direct methanol injection engine was simulated using the CONCHAS-Spray computer code. The input and comparison data was supplied from a Detroit Diesel Allison production engine operating on methanol fuel. Calculated values of both cranking and firing chamber pressure were lower than reported from the engine. The injected fuel did not entirely evaporate which caused regions of fuel impinging on the cylinder walls and piston face. The simulation did predict the formation and accumulation of formaldehyde in the regions of unburned fuel and is consistent with the theory that the formaldehyde does not readily decompose at low temperatures and forms from the incomplete oxidation of the fuel.

In order to meet the stricter and stricter emission regulations, cleaner combustion concepts for Diesel engines are being progressively introduced. These new combustion approaches often requires closed loop control systems with real time information about combustion quality. The most important parameter for the evaluation of combustion quality in internal combustion engines is the in-cylinder pressure, but its direct measurement is very expensive and involves an intrusive approach to the cylinder. Previous researches demonstrated the direct relationship existing between in-cylinder pressure and engine block vibration signal and several authors tried to reconstruct the pressure cycle on the basis of information coming from accelerometers mounted on engine block. This paper proposes a method, based on the analysis of the engine vibration signal, for the diagnosis of combustion process in a Diesel engine.

This AIR points out that above a frequency called the “transition frequency,” variances associated with the shielding effectiveness measurements can become large. It includes the derivations to demonstrate this. This fact should be taken into account when designing shielding for use above the transition frequency.

An unconventional conceptual design of truck chassis with multi-functional cross-members is proposed, and an optimization framework is developed to optimize its structure to minimize mass while satisfying stiffness and modal frequency constraints. The side rails are C-sectional channels of variable height and were divided into six sections, each with different thickness distribution for the flanges and the web. The gearbox cross-member and the intermediate cross-members are compressed-air cylinders, and hence they act as multi-functional components. The dimensions and thickness of the side rails and the air-tank cross members are defined by a set of parameters which are considered as design variables in the optimization problem. The structure consists of three additional fixed cross-members which are modeled using beam elements. The limits of the design variables are decided while considering manufacturing limits.

This procedure covers ultrasonic inspection of tubular, centrifugally-cast, corrosion-resistant steel cylinders.