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Technical Paper

Utility Trucks, Cabs, Bodies and Auxiliary Equipment

BY means of representative cases this paper shows some of the marked developments in utility fleets in the past 41 years. Among the examples discussed are a horse-powered truck of 1896, one of the first motor trucks used for the purpose in 1910, a number of light modern “mosquito-fleet” units adapted for special applications from light-weight passenger cars, heavier units with five- or seven-man cabs, and highly specialized units for erecting poles and pulling-in underground cables with their trailers and auxiliary equipment. Considerable technical information on the design and construction of these special bodies and their auxiliary equipment is presented. In conclusion the author recommends four general objectives for consideration in rebuilding a fleet.
Technical Paper

Utility Construction-A Growing Industry

Involved in implementing environmental programs such as the one established by the 1972 Federal Water Pollution Control Act, utility contractors are part of a growing industry which already accounts for annual equipment purchases worth millions of dollars. The problems encountered in this type of contracting and how they are affected by equipment design and maintenance are discussed. The major ways in which equipment manufacturers could improve their products and services to better provide for the needs of this industry are also outlined.
Technical Paper

Using Personal Computers in the Hydraulics Test Lab

Low cost personal computers provide a sophisticated and flexible tool for applications in a hydrostatic development laboratory. These microprocessor based computers can provide increased productivity in clerical tasks as well as providing logical intelligence to electronic control, data acquisition and safety monitoring of hydraulic test stands. This paper presents an overview of computer interfacing and discusses some applications that are now being used in a hydrostatic development lab.
Technical Paper

User's Perspective-Equipment Maintenance and Repair Management

Some concepts and methods of Equipment Maintenance and Repair Management have been defined, which include resulting management information, its evaluation and use, and the philosophy underlying the theory of centralized control in Equipment Maintenance Management. The environment of centralized control not only provides for a high degree of measurable accountability but also establishes a structure of proper incentives for managers. The effectiveness of such a system is directly related to the accuracy and selectivity of the methods employed to gather and report data. A successful Equipment Maintenance and Repair Management program will help the dealer and manufacturer if they support the end user by utilizing the data available to improve their operations.
Technical Paper

Use of the Hydraulic Ohm to Determine Flow Distribution

Determination of flow distribution is important in many types of fluid power machines. The life and proper operation of engines, transmissions, and fluid power equipment is dependent on satisfactory flow distribution of oil in the passages of the circuitry. Use of the hydraulic ohm provides a simplified and accurate method for determination of flow distribution and associated pressure values. The method provides a rapid solution and eliminates the need for the iterative type procedures commonly used.
Technical Paper

Use of Tractor Equipment on the Mississippi River Levees

MAGNITUDE of the Mississippi River flood-control work and the huge quantities of earth that must be moved in the building of levees in the South require tractors of the largest commercial sizes and varied dirt-moving machines and wagons to perform the work expeditiously and economically. The author describes briefly the types of tractor and tractor-operated equipment used by the contractors as he observed them at work on two visits to the South. How several hundred tractors are regularly used for hauling crawler-track dump wagons, pulling blade graders and elevating graders, pushing bulldozers and supplementing tower machines and drag-lines is described, and the author pictures vividly the severity of the work, which requires continuous operation for 20 to 22 hr. per day, seven days per week, and the crude provisions for and methods of maintenance, as a consequence of which the machine casualties are heavy.
Technical Paper

Use & Benefits of Inexpensive Diagnostic Tools

The heavy vehicle industry has become more complex due to amount and capability of the Electronic Control Units (ECUs) used on a vehicle. Today's ECUs require the use of diagnostic tools to perform various tasks such as troubleshooting, configuring, enabling features, and downloading firmware. There are a wide variety of diagnostic devices, from the simple easy to use low cost versions, to the more complex higher cost variants. Some of the lower cost diagnostic tools offer distinct advantages in their simplicity and usability, compared to the complexity of the higher cost devices.
Technical Paper

Urea-SCR-Technology - Performance of Structured Metallic Substrates

SCR technology has proven its ability to significantly reduce NOX emissions to fulfill future emission legislations. The key to this technology is the generation of ammonia on-board to reduce the NOX. Ammonia generation catalyst systems need to be highly efficient in a limited packaging space. The influence of physical parameters of the catalyst's substrate such as thermal mass, hydraulic diameter and geometric surface area on catalyst's efficiency is well known, but the transport processes in structured metallic substrates are still an object of investigation. A numerical study for 3 structured substrates was carried out, and the results were compared with experimental data. An increase of the volumetric efficiency was found when structured substrates were applied. The numerical results are in good accordance with the experimental data and therefore proven to be an excellent tool for channel design optimization.
Technical Paper

Update on the Comprehensive Truck Size and Weight Study

This paper describes the analytical framework underlying the U.S. Department of Transportation's (DOT's) 1998 Comprehensive Truck Size and Weight (TS&W) Study. The purpose of the Study is to provide a policy architecture within which the Nation's current body of TS&W laws may be assessed. The analytical framework provides a structure for assessing the impact of alternative TS&W policy options. Data and analytical tools have been developed to evaluate critical impact areas: highway agency costs (pavement preservation, bridge protection and geometric requirements), safety of the system, environmental quality, energy consumption, traffic flow, rail and shipper costs. The DOT identified a set of illustrative core scenarios for initial evaluation. Scenarios were specified using a building block approach which includes configuration, highway network and geographic options.
Technical Paper

Unified System for Compactor Performance Specification

A comparison of expected performance of the vast number of different compactors available today cannot be made using data normally given on equipment specification sheets. A unified system is presented for combining the essential information into expressions for compactive effort, productivity, and power requirements. This approach is practical and may be used now by designers or users of the compactors, but further development of the system is also encouraged.
Technical Paper

Understanding Software Process

How shall we improve the quality and reliability of the software we produce? We believe that the critical factor is an understanding how software is constructed, and why it is constructed in that way. Once something is understood, we can begin to build better tools to support and mold the process. This paper outlines a view of how the software process proceeds, why it proceeds that way, and how we can use this perspective to build better tools.
Technical Paper

Unattended System for Recording Machinery Transients and for Validation of Trending Algorithms

A digital data acquisition system was developed for unattended data collection and reduction for use aboard US Navy vessels. Data obtained will be used for performance evaluations, validation of trending algorithms, equipment failure analysis, and generation of operating profiles. The system consists of a shipboard data acquisition unit and a desk-top data reduction processor/report generator. Both units are portable. The shipboard unit operates unattended (except for periodic replacement of the data storage media), is user-configurable, contains a 20-minute uninterruptible power supply, and can monitor up to 64 channels, 32 boolean and 32 analog. Software was developed to support periodic data logging, cumulative signal level versus time profiles, high sample rate look-back for out-of-limit conditions, CRT displays, and interactive system configuration by the user. An application of the system for long terra profiling is described.
Technical Paper

Trucks as of 19-

THE first part of this paper is given over to Mr. Bachman's reply, as a truckmaker, to the paper by Mr. Laurie, which gave the operators' requirements for post-war trucks. After discussing the operators' requirements for cooling systems, electrical equipment, unit replacement, and cabs, Mr. Bachman indulges in some crystal gazing. In general, it may be said that Mr. Bachman does not anticipate any sudden changes in trucks, regardless of how passenger-car development proceeds.
Technical Paper

Truck/Mobile Equipment Performance Monitoring Management Information Systems (MIS)

Truck/Mobile Equipment Performance Monitoring is a vital part of every mining operation. Performance Monitoring identifies current performance baselines for use in analyzing, refining, and improving equipment performance levels. Further, to be meaningful, equipment monitoring requires real time data collection. Equipment Performance Monitoring is the key to building a Management Information System leading to Computer Integrated Mining.
Technical Paper

Truck Mounted Utility Winches and Drive Installations

Utility winches are reliable and durable pieces of equipment. Their installation on the truck chassis frame is not difficult to accomplish. However, as pure mechanical drives become more complex, the problem of proper location and configuration is intensified. In this connection, hydraulic motor drives offer improved flexibility and reduced installation problems at the sacrifice of some power loss. Although considerable progress has been made in the technical development and application of constant load utility winches and hydraulic drive installations, important advances are still to be realized, especially with regard to achieving higher efficiency and more compact design units.
Technical Paper

Truck Driver Selected Seat Position Model

A truck driver selected seat position tool has been developed to describe where certain percentages of truck drivers position horizontally adjustable seats in various workspace arrangements. The curves describe the 2.5th, 5th, 10th, 50th, 90th, 95th, and 97.5th percentile accommodation levels expressed as H point locations aft of the Accommodation Heel Reference Point as a function of vehicle H-point height (H30). Separate equations describe the accommodation level for driver populations with male/female percentages of 50/50, 75/25 and from 90/10 to 95/5. The equations can be used as a design tool to estimate the location and length of horizontal seat travel to provide accommodation of target percentages of truck drivers. The equations can also be used as a checking tool to estimate the level of accommodation provided by a given horizontally adjustable seat track.