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Weldability study has been performed on Polypropylene (PP) and PC/ABS samples to investigate how the paint layer along the weld joint affects the vibration weldability. The plastic used for this study were PP representing semicrystalline thermoplastics and PC/ABS representing amorphous thermoplastics. Both resins were molded to generate sample plaques for the study. Design of Experiment (DOE) studies were initially conducted with unpainted plaques and then repeated with the painted plaques for comparison. Optimal welding parameters were determined through DOE and the maximum weld strength under optimized welding conditions were determined and compared. Following each DOE, a regression analysis, using the weld strength as a response, was performed.

An experimental evaluation to systematically study a hot air cold stake joining process was conducted with injection molded samples. Twelve material combinations consisting of six stud plate materials were matched with two hole plate materials (GDT 6400 and 18% talc filled PP). Seven stud designs with variations in size and geometry were used for each material combination. A proper heating temperature was first determined by heat characterization trials. Different heating times and stake heights were studied in the staking experiments. Pull tests were conducted to determine the strength of the joints and their failure mode. Results showed that material characteristics, material combinations, and process parameters all could contribute to variations in pull strength and different failure modes.

In automotive assembly facilities worldwide, many critical vehicle systems such as brakes, power steering, radiator, and air conditioning require the appropriate fluid to function. In order to insure that these critical vehicle systems receive the correct amount of properly treated fluid, automotive manufacturers employ a method called Evacuation and Fill. Due to their closed-loop design, many critical vehicle systems must be first exposed to vacuum prior to being flooded with fluid. Only after the evacuation and fill process is complete will the critical vehicle system be able to perform as specified. It has long been thought, but never proven, that humidity and entrenched fluid were major hindrances to the Evacuation and Fill process. Consequently, Ford Motor Company Advanced Manufacturing Technology Development, Sandalwood Enterprises, Kettering University, and Dominion Tool & Die conducted a detailed project on this subject.

A design framework based on the principles of lean manufacturing and axiomatic design was used as a guideline for designing an automotive component manufacturing system. A brief overview of this design decomposition is given to review its structure and usefulness. Examples are examined to demonstrate how this design framework was applied to the design of a gear manufacturing system. These examples demonstrate the impact that low-level design decisions can have on high-level system objectives and the need for a systems-thinking approach in manufacturing system design. Results are presented to show the estimated performance improvements resulting from the new system design.

A simulation study was undertaken to help design a material delivery system to support lean manufacturing in an automotive body shop. Since this was a greenfield facility, simulation analysis was employed in the very early design phase of the system to determine and quantify the limiting parameters of the proposed lean material delivery system. The simulation analysis evolved with the changes in the design parameters and assumptions of the facility. The updated information from the simulation model helped the designers to evaluate alternate concepts and understand some parameters better such as, traffic congestion, manpower, and storage area requirement.

Plastics are largely regarded as commodity materials. However, they differ considerably from the materials which we became acquainted with during our college education. Although one can proceed to design plastic components and manufacture them without seriously considering a training program, the consequences can be substantial sacrifices to quality, development cost, part cost, and time to market, as well as adding a great deal of unnecessary stress to the workplace. This presentation explains why plastics are different and recommends a training curriculum that should be a part of strategic planning.

The engineering community is becoming increasingly aware of the significant benefits of performing error proofing on product and tooling designs. If a part or tooling can be designed or redesigned to allow for one-way assembly, the option of incorrect assembly at the plant is eliminated, making the process more robust. The goal of the error proofing exercise is to reduce operator decisions, eliminate misbuilds, and improve quality. Through participation in this type of exercise, all key stakeholders, including product, process, tooling, and production personnel, have greater opportunity to identify, prevent, and resolve potential production issues well in advance of launch.

The linked cell system gives both reduced cost and volume flexibility. The characteristics of the linked cell system are a consequence of decoupling the operators from the machines, using standard work in process between the cells and by integrating the information system with the cell and system design. By decoupling the operators from the machines the capacity can be increased/decreased in small increments by using more or fewer operators in the cell. The information system is integrated with the linked cell design by the use of a Heijunka box. The Heijunka is used to level production and to initiate the pace of production as a result of pulling withdrawal kanban at a standard time interval. This standard time interval is called the pitch of production. The kanban cards give information about what to produce, when to produce, when to make changeovers but they also give information to control the material replenishment.

Lean production has greatly influenced the way manufacturing systems should be designed. One important aspect of lean production is takt time. Takt time relates customer demand to available production time and is used to pace the production. This paper applies the manufacturing system design and deployment framework to describe the impact of takt time on both the design and the operation of a manufacturing system. The goal of this paper is to illustrate the relevant relationships of takt time to overall system design.

This paper provides twelve rules to help reduce four key ergonomic risk factors (force, frequency, posture and mechanical stress). These rules were developed to assist individuals who may not have received extensive ergonomic training but who are involved in implementing any changes (major or minor) to manufacturing work stations. This includes changes in task and/or changes in equipment. A complete ergonomic analysis of a work situation is a good idea in most cases, but these rules will avoid many of the commonly occurring problems if applied early in the design or modification of a workplace.

There are many analogies between the development of education and industrial development in the United States during the 1900s. In both segments of our society the emphasis on quantity of output led to the use of ever more specialized tools and concepts with sub-optimization often reducing the overall output quality. More recently both education and industry, especially the manufacturing sector, have recognized the value added concepts of integration, i.e., applying a holistic approach to their operations. In so doing a new workplace has been defined, the “High Performance Work Organization” (HPWO) (1). The discussion of the effects this development has had on manufacturing of goods and services is left to other presentations in this conference. This presentation focuses on an example from education which illustrates how integration of experiential and academic activities has been set as the cornerstone of a new construct for engineering education.

This paper discusses the evolution of graduate education in manufacturing engineering and the curriculum needed to educate manufacturing engineers in the automotive industry. This paper examines the master's and doctoral curriculum in manufacturing engineering at the University of Michigan-Dearborn. Finally, it proposes future direction for graduate education in manufacturing that will be needed for the automotive industry of the future.

Plastics manufacturing technology is rapidly changing. The use of process simulation to increase competitiveness has proliferated. Visteon Automotive Systems is committed to developing competent workforce and niche capabilities in plastics processing simulation. In this paper the current capabilities and future development plan for plastic process simulation are discussed. An integrated concurrent engineering process has been developed and implemented to deliver high quality robust plastics automotive products and systems. This paper highlights the technological advancements achieved by Visteon in the field of analytical simulation of common manufacturing processes. In addition, future development initiatives towards the technical competency in plastics manufacturing simulation are discussed throughout the manuscript.

Gasolines and diesel fuels of wide source were analyzed with the aim to predict the quality through the mid infrared spectroscopy and the algorithms PCA-PCR and PLS. The results revealed that octane number, cetane number, MTBE, benzene, aromatics and specific gravity could be predicted with good reliability. The other relevant fuel physical-chemical characteristics were beyond the precision of the standard test methods.

The Coordinating Research Council conducted a program to measure the reversibility of fuel sulfur effects on emissions from California Low Emission Vehicles (LEVs). Six LEV models were tested using two non-oxygenated conventional Federal fuels with 30 and 630 ppm sulfur. The following emission test sequence was used: 30 ppm fuel to establish a baseline, 630 ppm fuel, and return to 30 ppm fuel. A series of emission tests were run after return to 30 ppm to ensure that emissions had stabilized. The effect of the driving cycle on reversibility was evaluated by using both the LA4 and US06 driving cycles for mileage accumulation between emission tests after return to 30-ppm sulfur fuel. The reversibility of sulfur effects was dependent on the vehicle, driving cycle, and the pollutant. For the test fleet as a whole most but not all of the sulfur effects were reversible.

FTP-UDDS (urban dynamometer driving schedule) exhaust particulate matter (PM) emission rates were determined for 361 light-duty gasoline (LDGV) and 49 diesel passenger vehicles ranging in model year (MY) from 1965 to 1997. LDGVs were recruited into four MY categories. In addition, special effort was made to recruit LDGVs with visible smoke emissions, since these vehicles may be significant contributors to the mobile source PM emission inventory. Both light and heavy-duty diesels where included in the passenger diesel test fleet, which was insufficient in size to separate into the same MY categories as the LDGVs. Vehicles were tested as-received in three areas: Denver, Colorado; San Antonio, Texas; and the South Coast Air Quality Management District, California. The average PM emission rates were 3.3, 79.9, 384 and 558 mg/mi for 1991-97 MY LDGVs, pre-1981 LDGVs, smoking LDGVs and the diesel vehicles, respectively.

Shoebox catalytic converter design to securely mount thinwall substrates with uniform mounting mat Gap Bulk Density (GBD) around the substrate is developed and validated. Computational Fluid Dynamic (CFD) analysis, using heat transfer predictions with and without chemical reaction, allows to carefully select the mounting mat material for the targeted shell skin temperature. CFD analysis enables to design the converter inlet and outlet cones to obtain uniform exhaust gas flow to achieve maximum converter performance and reduce mat erosion. Finite Element Analysis (FEA) is used to design and optimize manufacturing tool geometry and control process. FEA gives insight to simulate the canning process using displacement control to identify and optimize the closing speed and load to achieve uniform mat Gap Bulk Density between the shell and the substrate.

In this study, feasibility tests of secondary air injection technology and lean A/F control technology were performed for LEV program using the FTP75 test on a 2.0 DOHC A/T vehicle. Second-by-second emissions and temperatures were evaluated. The temperatures of exhaust gas were measured at exhaust manifold, front of warm up, and the center of warm up converter. At first, amount of secondary air injection was determined with a bench aged warm up converter and a fresh UCC. And then, the performances of secondary air injection and lean A/F control strategy were compared with 80,000km vehicle aged converters(warm up converter, UCC). Both secondary air injection and lean A/F control technologies satisfied the ULEV regulation. This study shows that the lean A/F control strategy can be one of the potential technologies to meet the LEV/ULEV regulations without an active system that need a cost up.

The shape of unit cell of catalytic converter has great influence on the conversion efficiency and pressure drop characteristics. Therefore, the properties of design parameters of catalyst monolith were analyzed and the parameters of various cell shapes of catalyst were compared. Also, the numerical study of a three dimensional compressible flow in a Close-coupled Catalyst Converter (CCC) system was performed to investigate the flow characteristics and the flow distribution of exhaust gases. Unsteady flow analysis shows that severe interferences of each pulsating exhaust gas flow as well as geometric factors (junction, mixing pipe, cell shape etc.) influence greatly on the flow uniformity and flow characteristic in substrate. The results can be applied for the catalytic converter design.

Although the intent of the SHED test (Sealed Housing for Evaporative Determination) is to measure evaporative fuel losses, the SHED sampling methodology in fact measures hydrocarbons from all vehicle and test equipment sources. Leakage of air conditioning (AC) refrigerant is one possible non-fuel source contributing to the SHED hydrocarbon measurement. This report describes a quick and relatively simple method to identify the contribution of AC refrigerant to the SHED analyzer reading. R134A (CH2FCF3), the hydrofluorocarbon refrigerant used in all current automotive AC systems, as well as its predecessor, the chlorofluorocarbon R12, can be detected using the gas chromatography methods currently in place at many emissions labs for the speciation of exhaust and evaporative hydrocarbon emissions.