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“Today, wearing parts are regularly subjected to abnormal loading conditions. They must be able to accept these conditions without failure. In continuous operations, unscheduled downtime greatly increases maintenance costs, not to mention the cost of lost production. White iron castings offer premium abrasion resistance for many of these applications, but are often not used due to the possibility of brittle failure and the difficulty of mechanical attachment. This paper discusses the properties and applications of a composite of martensitic white iron and mild steel. This laminate will accept medium to high impact without loss of service failure, and can be installed by mechanical means or with welded attachment.”

The objective of this paper is to delineate the importance of pictures, i.e., graphical models, in documenting and communicating the high level functionality of a complex system, primarily for embedded software requirements and specifications. An overview is given of various graphical techniques and methodologies for modeling complex systems. The aspects (advantages and disadvantages) relating to different categories of modeling are outlined. Discussion of complex systems extends beyond the functional/software aspects of product design to both process and project modeling. The author shares personal observations and experiences with modeling, and tools used.

Effective requirements elicitation and management is a common need in supplier-OEM relationships, and continues to play a vital role in all aspects of the product development lifecycle. While traditional methods address the business goals for requirements and provide guidance in ensuring the accuracy of the “Descriptive-Prescriptive-Explanatory” outputs for requirements gathering and documentation, engineering organizations continue to encounter challenges with respect to capturing and communicating change, accommodating the addition of relevant design details and efficient propagation to inform development. These challenges become more difficult to overcome in mechatronic systems, which combine mechanical systems with integrated software. As software development can produce an overwhelming volume of information that requires accurate tracking and proliferation, it cannot be effectively managed using traditional hardware-centric systems.

A new Artificial Intelligence (AI) “Expert System” software technology has been developed which shows real promise as the core platform of the Decision Support System for Truck Repair. The “Expert system” consists of a Model Based reasoning mechanism, and a Rule Based shell along with an on-line documentation and graphics capability. This technology combines the development speed and accuracy of Model Based technology, the precision of Rule Based expert systems along with the ease-of-use associated with a “Hypertext” information system.

Low crew productivity and extension of service intervals past design limits are the two major reasons so many heavy equipment PM programs are ineffectual. ALPM, or Assembly Line Preventive Maintenance is an innovative system for equipment servicing, providing management scheduling tools and the necessary controls. The system has a successful track record in a number of severe applications.

This SAE Standard includes complete general and dimensional specifications for those types of pipe, filler, and drain plugs (shown in Figures 1 to 6 and Tables 1 to 4) commonly used in automotive and related industrial applications.

This standard includes complete general and dimensional specifications for those types of pipe, filler, and drain plugs (shown in Figs. 1-6 and Tables 2-4) commonly used in automotive and related industrial applications.

This SAE Standard includes complete general and dimensional specifications for those types of pipe, filler, and drain plugs (shown in Figures 1 to 6 and Tables 1 to 4) commonly used in automotive and related industrial applications.

Determining pre-impact acceleration and braking performance values is an important aspect of reconstructing collisions. Collision analysts may have to rely upon performance testing of an exemplar vehicle for reliable data to use in traffic collision reconstruction cases. These performance characteristics are well documented for many vehicle classes, but are limited when discussing urban transit style buses. The constant stop and go urban driving conditions in which they operate constantly challenge the vehicle components. Because of the heavy weights and operating conditions, auxiliary braking systems are often installed to prolong the life of the service brakes. A series of idle acceleration, maximum acceleration, and maximum braking tests were conducted using urban transit style buses that are currently in-service in a large metropolitan area. The initial braking target speed for these braking tests was 64 kph (40 mph).

This SAE Recommended Practice establishes minimum performance requirements for new pneumatic valves when tested in accordance with the test procedure outlined in SAE J1409. The performance requirements will include: a Input-output performance b Leakage characteristics c Low temperature performance d Elevated temperature performance e Corrosion resistance performance f Endurance testing g Structural integrity

This SAE Recommended Practice establishes minimum performance requirements for new pneumatic valves when tested in accordance with the test procedure outlined in SAE J1409. The performance requirements will include: a Input-output performance b Leakage characteristics c Low temperature performance d Elevated temperature performance e Corrosion resistance performance f Endurance testing g Structural integrity

This SAE Recommended Practice establishes minimum tolerance requirements for pilot operated and mechanically actuated modulating type valves, and through type valves used in the service brake control system when tested in accordance with the test procedure outlined in SAE J1859. This document applies to the nominal input-output characteristics as specified by vehicle original equipment manufacturer and labeled by the valve manufacturer as outlined in SAE J1860. The tolerance requirements will include: a Crack (opening) pressure or force. Crack pressure may be measured at the initial output pressure or as the pressure differential before output pressure exceeds 14 kPa (2 psi). Crack force may be measured at initial output pressure or before output pressure exceeds 14 kPa (2 psi). b Pressure differential (input-output)

This SAE Recommended Practice establishes minimum tolerance requirements for pilot operated and mechanically actuated modulating type valves, and through type valves used in the service brake control system when tested in accordance with the test procedure outlined in SAE J1859. This document applies to the nominal input-output characteristics as specified by vehicle original equipment manufacturer and labeled by the valve manufacturer as outlined in SAE J1860. The tolerance requirements will include: a Crack (opening) pressure or force. Crack pressure may be measured at the initial output pressure or as the pressure differential before output pressure exceeds 14 kPa (2 psi). Crack force may be measured at initial output pressure or before output pressure exceeds 14 kPa (2 psi). b Pressure differential (input-output)

This SAE Recommended Practice establishes performance guidelines of the air reservoir systems used on trucks, towing trucks, truck-tractors, trailers, and converter dollies with GVWRs over 10 000 lb designed to be used on the highway. NOTE: Compliance with this document does not guarantee compliance with the air reservoir requirements of FMVSS 121.

This book provides property and performance data for all types of aluminum alloy castings and reviews and describes the factors that contribute to and affect those properties, including composition, microstructure, casting process, heat treatment, and quality assurance. The electronic publication features extensive collections of property and performance data, including previously unpublished aging response curves, growth curves, and fatigue curves, presented in consistent formats to enable easy comparisons among different alloys and tempers. The authors have endeavored to address all of the casting process technologies available for aluminum alloys. Engineering information is included for expendable mold, permanent mold, and pressure die casting processes and their variations. The focus of the process coverage is to review the effects of process selection and process variables on casting properties and performance.

To compete with the current market trends there is always a need to arrive at a cost effective and light weight designs. For Commercial Vehicles, an attempt is made to replace existing Gear Shift Fork from FC Iron (Ferro Cast Iron) to ADC (Aluminum Die Casting) without compromising its strength & stiffness, considering/bearing all the worst road load cases and severe environmental conditions. ADC has good mechanical and thermal properties compared to FC Iron. Feasible design has been Optimized within the given design space with an extra supporting pad for load distribution. Optimization, Stiffness, Contact pattern has been done using OptiStruct, Nastran & Ansys for CAE evaluation. A 6-speed manual transmission is used as an example to illustrate the simulation and validation of the optimized design. Advanced linear topology optimization methods have been addressed as the most promising techniques for light weighting and performance design of Powertrain structures.

There is a growing emphasis on the transfer of testing from the proving ground to the laboratory. The rapid evolution of test technology has been a key to making such transfers possible. This paper presents a description of the methods, including the critical data acquisition and the control parameter generation processes, developed to efficiently perform the move from the proving ground to the laboratory. Software tools are described that permit the user to collect vehicle control and response inputs on the road and convert these to test system control parameters. The process of collecting data is shown to be straight forward with a great deal of flexibility in terms of the type and number of channels to be collected. The conversion of these data to control parameters is described with examples. Parameters included in these studies include speeds, loads, vehicle inclination, accelerations, temperatures, torques, pedal positions, pedal force, time and distance.

Utilizing public domain information sources and personal contacts with manufacturers, the National Highway Traffic Safety Administration has developed a computerized data base of corporate and product related information on the truck, truck-tractor chassis and trailer manufacturing segments of the trucking industry. This paper documents the development of this unique data base and presents an overview of the commercial truck and trailer manufacturing industry on the basis of data for model years 1982-1984.

Production cost saving is the main subject of process control of all automobile industries. Recently introduced ADI is a suitable material for those issues, but usefulness is restricted because of its poor fracture toughness. In the study, the effect of casting and austempering conditions on the fracture toughness of ADI were determined in order to develop a suitable material which can replace forged alloy steel. For casting of DCI, sandwitch method was conducted as inoculation process involving spheroldizing treatment with calballoy. Austempering was carried out in a salt bath with a composition of 50% KNO3 and 50% NaNO3 and then cooled in air. Two main parameters, namely austempering temperature and time, were selected as variables and structural changes of ADI with initial casting conditions was monitored with them. According to the casting results, it was confirmed that the mechanical properties of ADI, especially fracture toughness, depends strongly on casting conditions of DCI.

IQ Technologies Inc (IQT) of Akron, Ohio, conducted extensive experimental and computational studies to demonstrate the benefits of intensive water quenching techniques for steel parts developed by Dr. Kobasko of the Ukraine. Two intensive quenching methods were applied: “direct convection cooling” (IQ-3 technique) and nucleate boiling (IQ-2 technique). Experiments and calculations were performed for a variety of steel products including automotive parts (coil springs, kingpins, torsion bars, bearing products, etc.), fasteners of different types including automotive bolts, tool products (punches, dies, die-casting machine parts, etc.). Experiments were conducted in 500-gallon experimental intensive quenching systems installed at Akron Steel Treating Co.'s facilities and in the 6000-gallon full-scale intensive quenching system installed at Summit Heat Treating Co.'s facilities.