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This paper outlines what a large company is doing on a corporate staff basis to help combat Product Liability problems. Eaton Corporation is multi-national and serves a variety of markets. The extensive and complex line of products dictates the need for a well organized, corporate Product Assurance Program. The program is made up of five thrusts: 1) Corporate Policy, 2) Guidelines, 3) Divisional Committees, 4) Surveys and 5) Training. Utilizing a product development project, the implementation of several elements of Product Quality Assurance are explained. The program was designed for flexibility and emphasizes the chairman's motto to “DO IT RIGHT THE FIRST TIME, EVERY TIME.”

The material presented in this paper addresses the following questions of the engineer of the ‘80’s: 1. How can an (earthmoving) engineer be successful in the ‘80’s? 2. Should he isolate himself in his work? 3. Are there special needs in the ‘80’s? 4. What should he do-personally-to succeed and to improve the world in which we live? 5. Can the engineer help solve specific problems facing us now? 6. Can today’s problems-unemployment, inflation, world unrest, competition from new sources around the world, social unrest, energy limitations, pollution, and others, be met directly by the engineer with any success?

In order to predict the fatigue life of thrust rod heavy duty commercial vehicle balanced suspension, based on the continuum mechanics theory, the fatigue life prediction model of rubber with equivalent effect as damage parameter is established. Based on the equivalent stress and fatigue cumulative damage theory, the fatigue damage evolution equation of rubber material expressed by stress is derived by using the strain energy function. The general fatigue life model is established by using the maximum logarithmic principal strain as the damage parameter. The finite element model of the thrust rod is established, and the stress distribution of the spherical hinge rubber layer and the easy damage area are analyzed. Based on the equivalent stress calculation results and the axial tension stress and strain data of the rubber material, the accuracy of the results of the finite element calculation is verified.

Among the excitation sources of vibration for the marine propeller shafting, the propeller itself plays a significant role. It is the main source of excitation for the axial vibrations and a major contributor among the excitation sources for torsional vibrations. Thus, the possibility to predict the harmonic structure of the torque and thrust, in the design stage of the propeller system has a great importance for the designer. In this direction, the paper presents an analytical method of calculation for the propeller torque and thrust based only on the propeller series diagrams and general empirical formula for the wake and suction coefficients. A vortex model of the marine propeller, based on Prandtl lifting-line theory, has been developed. Considering the system of bounded and free vortices representing the propeller blade and its interaction with the incipient wake generated by hull motion, the velocity field around the blade profile is determined.

In order to study the static and dynamic characteristics of the thrust rod. Based on the multi-body dynamics theory, the dynamic model of the thrust rod and the vehicle system is established by using ADAMS software. The limit braking condition is simulated, and the limit braking load of the thrust rod is obtained. Thrust rod finite element model is established, the load calculation value and rubber test data as a finite element analysis of input conditions, using ABAQUS software to carry on the stiffness and strength analysis, analysis results show that the strength meets the requirement, and the stiffness and strength calculation result is in good agreement with the sample test, accurately describes the finite element model. The analytical method used can be used to predict the stiffness of the thrust rod.

A hybrid (hydrostatic and hydrodynamic) model applicable to thrust bearing and hydraulic machine port plate is presented here. The model is based on Reynolds equation and variable viscosity effect is considered. Assumptions made are listed. Regardless of the assumptions, the model agrees with experimental results and can be used with minor restrictions for new hydraulic machines' and bearing design. Balance factor as a function of speed of rotation, gap height, barrel inclination and fluid viscosity is presented. The variable viscosity effect makes analysis more accurate for certain conditions when port plates' failures are likely.

The concept of Design Engineers having “Constituents” and the framework for responding to those constituents through the design phase of machinery is developed. A liberal arts complement to the Engineering profession and the complications brought on by time and change are examined. The characteristics of a rational approach involving leadership, diversity, and self-doubt are explored. Author concludes that the Design Engineer must remain an entrepreneurial person.

Filtering the road unevenness, i.e. comfortable ride for passengers, and vibration and shock isolation for freight, is one of the main thrusts behind the development of active and semi-active suspensions. For control of these systems, a variety of different schemes, mainly from the linear stochastic control area, have been proposed by researchers: and 1/4-car active and semi-active suspension models are used to simulate these schemes. Besides the main input an exogenous input is also considered, namely a velocity disturbance originating from the road unevenness. In most of the literature in this area, this disturbance is considered as white noise, which it hardly is. This a-priori statistical description of the disturbances, is necessary for using stochastic control techniques. In this paper, a comparison of some of these control schemes is performed.

The axial load carrying capacity of cylindrical roller bearings is not primarily related to the fatigue strength of the material, but to the lubrication conditions, and consequently the contact conditions between the roller ends and the guiding surface of the flange. Therefore, friction and attendant heat generation should be as low as possible at these contact positions. Analysis and testing have enabled the optimum geometric form for the roller end/flange contact to be defined with respect to minimum friction.

Now as never before electrical engineering is an exciting, fast-paced, and dynamic profession requiring life-long study for continued practice. University programs must provide the educational basis for each electrical engineering graduate's continuning professional development. Yet these programs are themselves experiencing forces and accelerations of crisis proportions during this present period of rapid change. This paper examines some aspects of our educational system that are rooted in the past, have served the profession well, but now are contributing undesirable force components. It also outlines the circumstances associated with the present expanding sphere of professional education, educational delivery systems, and explores the multi-facted impact of emerging microelectronics technology on electrical engineering education. Targeted are areas in need of streamlining, responsibilities of the profession in this time of challenge and ideas concerning industry support.

The contact fatigue life of a roller thrust bearing depends on the roller load distribution, which is dependent on the shape of the raceway surfaces under load. This presentation will show a finite element method of calculating the deflections of a partially backed up thrust race with nonuniform loading. This loading can be the result of an eccentric thrust load, or nonparallel raceway surfaces. A brief discussion of the theory will be presented along with a typical application.

The study of Leadership embraces three main phases: 1) Trait theories, 2) Style theories, and 3) Situational theories. Each of these positions is reviewed in this paper. It is suggested that leadership is a process of using skills to analyze each situation to determine the appropriate leadership style. Suggestions are given to help the manager with this analysis to develop better leadership skills.

To remain competitive the United States must change its way of doing business. We must learn to produce the highest quality product at a competitive cost. There are many things that must be done to attain this goal. This paper addresses only one - measurements. The role of measurements in the decision making process will be addressed. The main thrust is the discussion of the elements of a measurement, modeling a measurement and error analysis.

Incorporating tapered roller bearings in finite element and other structural analyses requires special considerations. Tapered roller bearing properties such as induced thrust, induced moment, load zone, and bearing stiffness can substantially affect the results of such analyses. This paper will discuss pertinent tapered roller bearing structural properties, two potential modeling techniques, and several examples on how bearing models were incorporated into structural analyses.

The material in this paper presents many facets of new technology which are becoming available, with a discussion of the subsequent effects on people in the Earthmoving Industry. Particular emphasis is placed on technological change as it relates to individual opportunity and professional growth for engineers.

For a growing number Friday is the day employees clear out their desks and move to a new job in a new organization. In many cases a result of unclear career orientation leading to frustration and dissatisfaction with their present status. Excessive attrition is expensive. This presentation will focus on a simple, visible communication tool HRD personnel and company supervisors can use to help subordinates access personal strengths and weaknesses, understand feedback on present performance, gain insights into the organizational structure, discover dysfunctional executions in the present work environment and match proper training with needs. First, we will examine a dual career path ladder and the resume base that supports both lateral and vertical career growth. Then we will explore why task performance and behavioral performance must be separated and how each can be used to help the employee prepare a plan for career development.

In this paper, the basic tractive characteristics and the optimization of the performance of four-wheel-drive off-road vehicles are analyzed from the point of view of tractive efficiency. It is found that the distribution of thrust and slip between the front and rear wheels has considerable effect on the efficiency of operation. Differences in theoretical speed and the type of coupling between the front and rear axles generally affect the thrust and slip distribution. It is shown that the optimum thrust distribution is that which can make the slips of the front and rear wheels equal. Only under such circumstances will the tractive efficiency of a four-wheel-drive vehicle be a maximum. This requires that the thrust distribution should vary with the weight distribution of the vehicle as well as terrain and other conditions. It is pointed out that the inefficient distribution of thrust and slip also causes excessive tire wear.

As new information-age technologies are developed and applied by the Earthmoving Industry, standards are increasing in importance. The keys to long-term competitiveness in today's global marketplace are products of better quality, produced at lower prices, delivered in record time. Manufacturers are constantly being urged to produce better products cheaper, faster and at a higher quality than ever before. In fact, measuring quality has become the benchmark for many products. A company must have, to survive and prosper, an in-depth quality system; one that will meet and exceed the demands of customers. The International Standards Organization (ISO) has developed standards by such a quality system can be developed. These standards help guide the companies, who become certified against them, to increasingly higher levels of quality. Smaller manufacturers need to pursue this certification but cannot do it alone.

Three case studies are presented which show how the finite element method can be used along with a general purpose bearing analysis program to better predict bearing stress and performance. The first case is a spherical roller thrust bearing where the objective was to determine the effect of shoulder diameter on the grind relief stress. In the second case a four point angular contact ball bearing was analysed to determine the effect of a circular cut-out section on the bearing stress and life. The third case is the study of the effects of housing clearance on the life of a cylindrical roller bearing. In all three cases, distortions calculated by the finite element program were input into the bearing analysis program to determine the effect of structural deformations on the stress and life of a bearing. A number of iterations between the finite element program and the bearing analysis program were required in order to reach convergence on roller loads.

In this paper some design aspects related to external gear pumps balancing surfaces are studied, and some useful guidelines for designing bearing blocks balancing surfaces are suggested. In order to study bearing blocks axial balance, a numerical procedure for the determination of the pressure distribution inside the clearance bounded by gears sides and bearing blocks internal surfaces is firstly presented and applied. After, the influence of bearing blocks geometry and pump operating conditions on the widening thrust is highlighted, considering both constant and variable lateral clearance heights. Then, the computations are performed to evaluate the widening thrust variation as a function of bearing blocks relative tilt with respect to gears lateral sides, and both positive and negative bearing blocks tilts are evidenced and discussed.