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The experience accumulated with a prototype 1000 HP diesel electric tractor since 1969 is described. The new 1500 HP V220 diesel electric tractors are described along with some of the initial operation of these two units. Experience with the initial 1000 HP unit and the two 1500 HP tractors confirm the necessity of additional testing and experimentation to refine the design to get greater productivity with reduced operator fatigue. The unpredictability of the load and operating surface are major problems that present a real challenge to the engineer.

The potential contributions of acoustical technology to manufacturing companies pervade nearly all of its functions from marketing and product planning to design engineering and quality control. Despite this, however, companies generally feel uneasy when they embark on programs to use acoustics in their operations because the technology seems complicated and somehow harder to “get a handle on” than it is in other cases. But the issues of product sound, and the benefits of acoustics on a diagnostic tool are too important to ignore, so in this paper we discuss these issues in a “20 questions” format to help planners, engineers and managers as they proceed to implement acoustical technology in their organizations.

Parameters like brake mean effective pressure, mean velocity of the piston, hardness of the wear surface, oil film thickness, and surface areas of critical wear parts are similar for all the diesel engines. The mean piston velocity at the rated speed is nearly the same for all the diesel engines. The mechanical efficiency normalized to an arbitrary brake mean effective pressure (bmep) is dependent on the size of the engine. The engine life seems to be proportional directly to the square of a characteristic dimension namely, cylinder bore of the engine and inversely to speed and load factor for engines varying widely in sizes and ratings.

A pin and disc machine has been modified for the evaluation of silver-steel lubrication characteristics of railroad diesel oils. Use of silver pins on polished steel discs at selected loads and rubbing speeds allows good correlation with known engine behavior. In comparison with wear and friction data obtained by the four ball method, this pin and disc test gives better correlation with engine tests than the Modified Four Ball Test.

A braking force distribution strategy in integrated braking system composed of the main braking system and the auxiliary braking system based on braking pad wear control and hitch force control under non-emergency braking condition is proposed based on the Electronically Controlled Braking System (EBS) to reduce the difference in braking pad wear between different axles and to decrease hitch force between tractors and trailers. The proposed strategy distributes the braking force based on the desired braking intensity, the degree of the braking pad wear and the limits of certain braking regulations to solve the coupling problems between braking safety, economical efficiency of braking and the comfort of drivers. Computer co-simulations of the proposed strategy are performed.

A cartridge type pivotal pin and bushing joint has been patented and is being tested and refined both in the laboratory and on construction machinery. It features “dry lubricated” (Teflon) bearings which are assembled and sealed prior to installation. It is suitable for heavy unit loads and use under severe wear conditions, such as in crawler track chains and loader bucket pivotal pin joints. A brief history of U. S. manufactured track pin joints is included to show the progress in extending the service life of these devices.

Current trends in application technology indicate an increasing realization on the part of manufacturers and users of agricultural chemicals of the important role that application techniques and/or equipment play in the overall success of pesticide application. The trends that are most significantly influencing the way chemicals are currently applied include: increased emphasis on improving the accuracy of application increased use of low volume application (3-8 GPA) renewed interest in use of granular application increased use of conservation tillage increased emphasis on reduction in environmental contamination, both within and outside the target area increased use of highly active cam-pounds

Close-range photogrammetry (CRP) is traditionally based on a network captured with the camera lens at a fixed focal length. A zoom lens is not desirable without solving the intrinsic camera parameters for varying focal length and lens distortion. When using a zoom lens camera, multiple focal lengths can be used if the camera is calibrated for each varying focal length, but most consumer grade lenses are not designed to accurately return to (or stay at) mid-range focal lengths. Similarly, using close-range photogrammetric software systems to accurately recover three-dimensional (XYZ) data from Point and Shoot (PAS) digital cameras has been problematic when the images were not intended for CRP. PAS cameras are automatically refocused and easily zoomed so the focal length and lens distortion are typically unknown for CRP mensuration purposes. In such circumstances, traditional CRP analysis can be both laborious and difficult without the correct camera parameters.

The objective of this paper is to demonstrate that frequency domain methods for calculating structural response and fatigue damage can be more widely applicable than previously thought. This will be demonstrated by comparing results of time domain vs. frequency domain approaches for a series of fatigue/durability problems with increasing complexity. These problems involve both static and dynamic behavior. Also, both single input and multiple correlated inputs are considered. And most important of all, a variety of non-stationary loading types have been used. All of the example problems investigated are typically found in the automotive industry, with measured loads from the field or from the proving ground.

To date, no definitive work to quantify and compare the braking rating horsepower relationships between vehicles equipped with brake assemblies containing asbestos, non-asbestos, and semi-metallic friction material has been completed. This paper will report the results of a brake fade evaluation performed on a 34,000-lb. GVW vehicle in accordance with SAE J880 Brake System Rating Test Code Procedures and has quantified braking horsepower, fade temperature resistance, thermal response temperature rise, lining wear, and drum wear.

This paper focus on some of the fatigue methodologies based on the frequency domain and how they can be used on the heavy vehicle industry. A calculation flow was developed which consist of two steps. At first the stresses on the desired frequency bandwidth are calculated using a finite element software and those are then used as inputs on a Matlab script that estimate the expected life using two different theories, Bendat’s narrow band and Dirlik. The proposed methodology is then compared with more established time domain calculations. At first a plain hand calculation with a simpler input is performed on both domains before evaluating the differences with a more complex random stress signal input. Finally, test data from a rig test is used to validate the frequency domain fatigue methods using real life data.

Frequency domain testing has had limited use in the past for durability evaluations of automotive components. Recent advances and new perspectives now make it a viable option. Using frequency domain testing for components, test times can be greatly reduced, resulting in considerable savings of time, money, and resources. Quality can be built into the component, thus making real-time subsystem and full vehicle testing and development more meaningful. Time domain testing historically started with block cycle histogram tests. Improved capabilities of computers, controllers, math procedures, and algorithms have led to real time simulation in the laboratory. Real time simulation is a time domain technique for duplicating real world environments using computer controlled multi-axial load inputs. It contains all phase information as in the recorded proving ground data. However, normal equipment limitations prevent the operation at higher frequencies.

This paper describes the results of a series of fatigue studies relating the lives of several weld geometries. Rotating beam and axially loaded specimens were used. A comparison between steel and plastic (polyvinylchloride scale models is made. Using plastic scale models of welded structures for fatigue life determination is the ultimate goal of this work.

Regulatory requirements in the European Union (EU) for off-road machines and road vehicles are different. Vehicles which transport passengers and goods, along with attached trailers, as well as road motorcycles must meet EEC type-approval requirements. All other types of self-propelled machines must meet the requirements of the Machinery Directive (Council Directive 98/37/EC), and the Electromagnetic Compatibility (EMC) Directive (Council Directive 89/336/EEC) and possibly other directives. This includes such categories as agriculture and forestry machines, construction machines, industrial trucks and similar products. The various directives outline the different processes for demonstrating compliance with the EU requirements. The intent of this paper is to summarize a few of the requirements that are of interest to off-highway equipment manufacturers and to identify some sources of information about the regulatory requirements.

“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.”

Predicting fatigue performance in concentrated contacts under thin film (or mixed) lubrication conditions has historically involved various empirical approaches. Typically a lubrication parameter is used in an experimentally derived equation to predict the expected rolling contact performance. However, this model doesn't explain the performance improvements. Enhanced finish bearings have exhibited longer life than standard finish bearings, especially when bearings are operated with thin EHL film. In this paper, the contact surfaces of test bearings were analyzed by using a micro-macro contact model in which the macro-contact was elastic contact, and the micro-contact was elastic-plastic contact. The interior subsurface stress maps were calculated from the real contact surfaces, which included the effects of roughnesses, waviness, and profiles.

A software tool has been developed to aid designers and process engineers in the development and improvement of heat treat processes. This tool, DANTE™, combines metallurgical phase transformation models with mass diffusion, thermal and mechanical models to simulate the heating, carburization, quenching and tempering of steel parts. The technology behind the DANTE software and some applications are presented in this paper.

On January 10th, 1972, an S. A. E. Paper “Lighting System Performance and the Computer as a Maintenance Tool” (720087) was presented by Charles J. Owen. This was a paper presented on the causes, effects, corrections and a study in good and bad electrical wiring, presented pictorially as well as editorially. We recommend that paper to you for reading. On November 4th, 1974, S. A. E. Paper “A Case for Standardization” (741143) was presented by Charles J. Owen. The purpose of this paper was intent on “improving the breed”. The recommendations and specifications were very specific. In view of the two previous papers, this paper is presented specifically for the designer with back-up data involving recommendations that the industry have generally accepted as applied to the electrical wiring systems The practical data included, is a first in relating indexes of performance and indexes to cost comparisons. The usefulness of this paper in aiding a Designer is the target of the authors.

Diesel powered vehicles are characterized by two distinctives, of particulate, sensed by sight, and odor, sensed by smell. Dramatically reducing these distinctives would result in a “clean diesel”. A joint program of Yellow Freight System, Inc. (YFS) and the author's employer (DCI) has addressed one distinctive (particulate) and has resulted in an exhaust filtering system for the diesel forklift trucks YFS use to move freight at their terminals. This paper covers design, installation, and testing of the system to filter the particulate emissions emanating from these forklifts. The filters, designed to operate for one programmed maintenance (PM) cycle, are then cleaned in off-board equipment and returned to service for another cycle. All filter materials utilized are compatible with the 200°C normal maximum operating temperature, although short excursions to 260°C have not been detrimental.

Aiming at achieving the economy and safety of downhill brake process (running downward along a long slope at a constant velocity) of commercial vehicles, an integrated control strategy of the main brake system and auxiliary brake systems is proposed. Based on Electronic Controlled Braking System (EBS), the strategy distributes braking force to each brake system and each axle according to the thermodynamic feature of them and the wear loss of each brake lining, in order to achieve economy at the premise of safety. A simulation is conducted based on MATLAB/Simulink and TruckSim. Simulation results show that the strategy proposed could control the temperature of each brake system at a rational value, and the balanced wear loss of brake linings is facilitated, thus, the safety and economy of downhill brake is ensured.