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Utilizing suitable techniques and equipment, job operating conditions can be measured on an earthmoving machine. Recordings of these measurements are a guide to establishing laboratory test procedures and aid evaluation of the results for predicting component life expectancy. With such information, the engineer has an effective tool for designing a reliable product.

A method of reducing cumulative trauma injuries based on ergonomic job rotation In today's growing global market many companies are implementing activities to improve productivity and employee performance in order to produce more saleable value per employee. Because of increased performance many of these improvement activities have led to higher injury rates based on repetitive cumulative trauma. This session will deal with understanding the role and effects of ergonomics on the shop floor. It will demonstrate how to analyze each job based on ergonomic effects, categorize those jobs and develop a job rotation schedule based on simple ergonomics, which will allow operators recovery time from cumulative repetitive motion.

A computer simulation method of assembling parts of a mechanical assembly has been developed by Deere & Company to statistically analyze tolerance stack-up of complex two-dimensional and three-dimensional assemblies. It is called Assembly Variation Simulation System (AVSS). AVSS offers a way to predict the impact of design tolerance and manufacturing variation on assembly quality of a John Deere Crawler Track Chain/Shoe Assembly. This method identified both the amount of variation relative to specifications and the percent contribution of the major contributors to the variation. In addition. AVSS has been used on a variety of other assembly applications. It is a proprietary system presently being marketed.

New 75 and 90 kilowatt rubber tired log skidders have been recently introduced by John Deere. These machines have increased power and durability over the previous models to meet the increasing demands of the logging industry. This paper presents the major design features and components of these machines.

An eight speed, hydraulically controlled, stepped transmission was found to be the closest practical approach to the ideal for agricultural and industrial tractors. This paper describes the means used to obtain maximum reliability and operator acceptance. Proper spacing of speed ratios, automatic programing of modulated shift pressures, and close attention to minimizing torque loss during shifts were found to be of prime importance.

This paper discusses the Quad-Range transmission and Perma-Clutch power train components available on 1973 John Deere Row Crop tractors. It presents the design and explores some of the development aspects of the Perma-Clutch, powershifted planetary and gear train, transmission oiling system and control valves, and the unique gear shifting arrangement all which comprise the Quad-Range transmission.

A simple, open, post and index system is used for final alignment and joining of the fuselage and wings of a new passenger business jet. 19 manually actuated axes precisely move the wings, forward, and rear fuselage sections into position. Movement is accomplished with industrial jacking screws and positions recorded with precision linear potentiometers. Wing sweep, angle of attack, and dihedral are monitored and controlled. The axes positions are downloaded to data files for verification and data archiving. The Gulfstream G150 Join Cell's open architecture enhances access to fasten the main aircraft structure while maintaining flight critical geometry.

RESISTANCE WELDING IS the major process used for the mass production of sheet metal components but, when used on aluminium, problems arise because of the conductivity of the sheet, the rapid degradation of the copper electrodes and the tendency to solidification cracking of some alloys. It would therefore be advantageous if MIG spot welding could be applied under mass production operating conditions. This paper describes work conducted to try and understand some of the factors influencing the resistance and MIG spot welding of aluminium alloys and thereby develop simple operating procedures and equipment to permit their implementation in areas such as the vehicle fabrication.

Over the past several decades, significant gains in automobile fuel efficiency have been achieved through down-sizing, aerodynamic design and drive train improvements. As performance limits are approached in these areas, aluminum is being used to further reduce body weight by up to 40% compared to steel. In anticipation of the continued demand for more fuel efficient automobiles, aluminum sheet component unibody and extrusion and cast component space frame designs have been studied to address joining and structural performance. Joint geometries unique to specific body designs clearly illustrate the need for close linkage of the design and assembly functions. Joining and assembly methods that provide static and dynamic structural integrity, 15 to 20 year durability and that can be integrated into robust manufacturing systems are key to aluminum usage for auto body structure.

An experimental study was conducted to investigate the potential of spot joining aluminum with nylon using frictional heat. The process utilizes the heat generated by friction between a rotating tool surface and the aluminum sheet surface to melt nylon locally in the joining area and create a mechanical interlock between the aluminum and nylon sheets. Lap shear joint specimens were prepared using this process to investigate the effect of several parameters such as tool geometry, tool RPM, tool hold time, tool plunge depth and tool feed rate. Tensile tests were conducted to evaluate the joint strength and to investigate the failure mechanisms of the joint. Furthermore, the effects of cleaning the aluminum surface and baking of the nylon on the joint strength were also studied in this paper. Finally, friction heat generated joints were compared with adhesively bonded joints between aluminum and nylon.

The high performance, efficiency, and integrity demanded in advanced aerospace materials applications frequently require the matallurgical union of aluminum alloys to stainless steels. Salt-bath dip brazing and various plating techniques are currently used, but continuing research and development programs will undoubtedly produce other reliable methods of joining the two intrinsically dissimilar metals. The limitations of this bimetallic couple have been overcome, and satisfactory bonding has been achieved.

1006 steel clad aluminum has been used as a transition material to directly spot weld steel to aluminum. Advantages of the clad metal transition include the ability to spot weld with existing equipment and reduction of dissimilar metal crevice corrosion at the steel-aluminum interface. Sheet steel between 0.8mm and 2.0mm has been spot welded to aluminum between 0.8mm and 3.0mm in a variety of combinations with the transition material. This paper contains specific spot welding parameters for a variety of joints containing steel and aluminum at thicknesses normally encountered in body applications. The mechanism of weld nugget formation for aluminum-transition-steel joints is evaluated. Weld lobes established according to SAE and Aluminum Association guidelines are presented. The effect of electrode design on joint strength and heat balance are discussed.

In this study, a proposed new 3-in-1 process using the magnetic pulse welding (MPW) for welding similar and dissimilar metals and for hybrid joining between FRC and metals is developed. Welding between (a) AA1199 sheets and XES, (b) AA1199 and XSG which is zinc coated steel, (c) 5754-aluminum alloy and XES were performed and (d) hybrid joint between PA66-glass-FRC and 5754-aluminum was achieved. SEM observations and EDX analysis for the weld interface between aluminum and steel showed where detectable very thin layers of intermetallics and the wavy interface pattern typical for impact welding was identified. X-Ray microtomography observation for the joining region in the FRC showed the good state of the composite structure after joining. 3D numerical simulation using LS-Dyna was used for the selection of the welding parameters. Quasi-static lap shear testing for the welds revealed a failure in the weak metal sheet and not in the weld.

Galvanic corrosion and mechanical properties are major design considerations for bimetallic assemblies. Galvanic corrosion can lead to rapid degradation while welding of dissimilar metals such as steel and aluminum can lead to reduced structural stability. This paper describes a new concept in joining dissimilar metals involving the use of transition materials. The clad transition materials is composed of the dissimilar metals to be joined and effectively reduces the corrosion and mechanical problems associated with the system. Results of galvanic corrosion field tests and welding studies for transition materials are presented and several examples of automotive applications are cited.

Automotive anti-corrosion goals are being satisfied with the use of galvanized and galvannealed steels. The trend towards the zinc coated steel usage has necessitated major modifications in joining processes. It is the intent of this paper to describe and discuss how both the Arc and Resistance Spot Welding processes are being modified to successfully join these coated steels in today's automobiles. Zinc coated steels are being production welded with changes in the Gas Metal Arc welding electrode materials (flux core and silicon bronze consumable electrodes) and equipment. Also, changes in Resistance Spot Welding weld schedules and equipment are discussed.

As automotive companies increasingly incorporate lightweight materials into the new vehicles to improve fuel economy, development of joining technologies for different material combinations is also required. As a key mechanical fastening technology for dissimilar materials, self-piercing riveting (SPR) has been well established in joining aluminum and steel. However, the application of SPR on magnesium alloys was impeded mainly by the cracking issue resulting from its limited slip-systems at room temperature when magnesium was restricted to be on the bottom due to galvanic corrosion concern. To solve this issue without much modification on existing process, a concept of adding a layer of ductile material underneath of the bottom magnesium to receive the rivet is proposed. An experiment was designed to investigate this concept by joining a mild steel and a magnesium die casting with a ductile aluminum as a rivet receiver.

The experimental research vehicle ES3 body was realized by using various aluminum-joining technologies: MIG welding, laser welding, self-piercing riveting. These technologies were applied selectively to make full use of their individual characteristics, according to the body structure and joined materials. Of these technologies, self-piercing riveting is advantageous in several respects. Aiming to expand the application range of riveting technology, we developed a die that prevents cracks in joining aluminum casting, and a method to improve rivet driving in thick, multi-pile portion. We further studied the feasibility of aluminum rivets. This paper outlines the ES3 body structure and it's joining technologies used and introduces the further improvements we developed concerning self-piercing riveting.

During the last decades one of the main challenge in the automotive field has been weight reduction to satisfy the EU's demands concerning fuel consumption and environmental aspects. Consequently, various materials are being considered. Using different materials for different automotive parts requires advanced joining techniques. The present work deals with the most frequently used joining technique, namely resistance spot welding. Additionally, laser welding is being considered, since it is obvious that this technique is being used for more and more parts. Since the welds of the dissimilar joints have to fulfill demands concerning formability, corrosion resistance and fatigue, the overall goal of this investigation is to find the best welding or joining parameters to achieve optimal joint performance in terms of structural integrity and part requirement.