Search Results

Robustness encompasses every aspect of the way in which a 2K (two-part) structural automotive adhesive is made and used, from manufacturing and storage to dispensability, adaptability to different substrates and stamping lubricants, cure characteristics, strength, and durability. Illustration of the many facets of adhesive robustness are made using primarily 3M #5047, a 2K epoxy hem flange adhesive developed for bonding oily untreated metals. Areas of robustness covered include storage stability, surface oil accommodation, open time, and performance under various curing conditions. The recent introduction of adhesives having unique mix ratio control and NDT capabilities heralds new levels of adhesive robustness.

Global manufacturing has the individual automotive component plants, on virtually all continents, scrambling for the “edge” to be the most competitive manufacturer and thus be the producer of choice. To be competitive in price and quality and that over “the long haul” is a tall order, indeed. A lot depends on the machining processes producing the components that, assembled, make up the powertrain. While outsourcing other automotive parts might be the right economical and technological choice, to produce ones own engines and transmissions is still one of the areas of true “value adding” and also a matter of the manufacturer's image. Hence the industry's effort to offer ever better, more potent families of engines and transmissions. New, advanced machining processes have evolved recently, that make manufacturing more productive and predictable. The three areas most promising are: One-pass finish-machining High-speed machining (Near) Dry-machining

The use of vibro-acoustics measurements during manufacturing testing as an approach for detecting defects has been steadily gaining acceptance in the automotive industry. Several studies performed by Hughes and others have demonstrated that signature analysis of vibro-acoustic spectra can be a sensitive measure of product quality. However, the implementation of a vibro-acoustic test system in a production environment is not always straightforward. Additionally, test system implementation and support requires knowledge in instrumentation, signal processing, spectral analysis, and statistical analysis. The latter skill is especially important in the development and maintenance of templates that provide pass/fail criteria. Template generation has been recognized as an engineering intensive process. This article discusses an approach to developing a robust vibro-acoustic manufacturing test, issues typically encountered, and some selected case studies.

The challenge was to have small, machined fuel-control components with cross-holes absolutely burr-free; to the extent that any loose particulate would cause the final assembly to fail. Parts are produced on multi-station Rotary Transfer Machining Centers and must be deburred at the rate of 3,600 per hour. Electro Chemical Deburring (ECD) was chosen because of its ability to selectively deburr features while leaving critical sealing surfaces untouched. The goal was to automate the ECD process to achieve maximum efficiency with minimum operator input, while maintaining extremely close control.

The purpose of this paper is to outline a new approach for production outsourcing of complex cast metal parts. The paper details the steps in providing a smooth transition from a CAD file through production. The key to this transition is the successful creation of the production tooling on the first attempt. Significantly shortened lead times and proper implementation of concurrent engineering are the consequent results. The inability to produce production tooling (patterns and core boxes) prior to creating a first article part is the main weakness of traditional casting processes. Creating production tooling is an expensive process that requires long lead times. The foundry, in order to minimize its financial risk, seeks to avoid total fiscal responsibility for the many required steps in converting a CAD design into serial production, and therefore charges the customer accordingly.

Manufacturing problems frequently originate years earlier in new product development. Examples include products that are hard to build or don't fit the production process; too many or too few products; unprofitable products that consume a disproportionate share of overhead; and products that were simply too late for their markets. The problem is well understood; the difficulty is knowing what to do about it, and how to make effective changes that the entire organization will support. This paper presents a comprehensive yet practical approach to improving the new product development process. The emphasis is on an integrated approach that leads naturally to implementation of the improved process throughout the organization. The approach is to recognize that effective product development spans three dimensions: the process, the technology, and the organization.

This paper describes the development and validation of a Lagrangian-based finite element model for the aluminum extrusion process used to produce thin sections which are characteristic of tubing used in automotive air conditioners. Due to the large reduction involved in producing such tubing, extrusion ratios are between 500 and 2000. In order to study metal flow and establish baseline strains and strain rates in the process, a finite element model based on non-isothermal plane strain deformation was developed. Effective strain rates were predicted to be as high as 1500 s-1 in the weld chamber with effective strains reaching 4.0 in each wall. Billet cooling on the order of 20 °C occurs in the container and portholes of the die while significant adiabatic heating occurs as a result of deformation in the weld chamber.

As a process that enables the high-speed and continuous forming of lengthy materials with a constant cross-sectional configuration, roll forming offers much higher productivity than the stamping process. However, in case a change must be made to the shape of the cross section, the material must normally be stamped or joined with a part containing a separate shape. This affects productivity, increases the number of pieces, and degrades the material's appearance. This report describes the roll-forming technology that we developed, in which the cross section of the material can be changed gradually. This method adopts a system which uses a movable and rotatable roll-stand that enables high-speed, continuous roll-forming processes.

Owing to the complexities inherent in Stamping Operations, the research aimed at developing a better understanding of Stamping Operations, particularly within the Automotive Industry, has taken many different approaches with varying degrees of success. This paper focuses on the Black Box approach where it is accepted that the application of deformation theory governing the process to complex parts are not fully understood, merely that the process is a medium governing the interaction between the inputs and outputs of the process. A series of Factorial Design of Experiments were conducted on a large structural component of a current model automobile which had in the past shown itself to be relatively difficult to manufacture.

As automotive electronic systems advance, the wire harness is the mainstream for necessary wiring in resin-made motor-driven actuators with wire connection labor and purchased-parts accounting for the majority of costs. As a means to eliminating the harness, there is a method of forming the conductive material on the inside, but this method leads to cost increases when there is a comparatively large number of wires because the required die insertion time becomes longer and automatic insertion equipment becomes necessary. The following paper reports on an integrated high-speed process that combines stamping and injection molding into a single process.

Manual Materials Handling has been historically recognized as one of the more prevalent causes for work related lost time injuries. Many manufacturing facilities use Material Handling Systems (lift/ tilt tables, hoists, articulated arms), often to alleviate ‘ergonomic’ stressors as well as to optimize production. If not used appropriately, Material Handling Systems can create new ergonomic concerns, or in some cases increase the physical demands of a job. A strategy designed to optimize the fit between the operator, the appropriate equipment and the operation is addressed in this paper.

Relating costs to risk factors has long been the ideal in providing for proposed ergonomic solutions. Utilizing the theory that all processes can be described in terms of cost, and likewise, in terms of ergonomic risk factors, then one should be able to correlate ergonomic risk factors to cost for a specific process or activity. Systems Engineering and Activity Based Costing Methods should be utilized to attribute costs to their respective source. The application of ergonomic risk factors are often activity dependent. The correlation of ergonomic risk factors to costs are displayed via case study.

Using the latest technologies, manufacturers have developed new compact PLCs which work hand-in-hand with low-cost operator interfaces, offering machinery manufacturers a practical control solution for simple automation processes. Operator interfaces with out-of-the-box functionality create simplicity for the developer and greatly reduce start-up time. Other advances have decreased the size of the operator interface, allowing installation in a small space. Additional advances in size have been used in PLC design to create controllers that fit in the palm of your hand. The latest advances in Windows-based configuration allow easy addition of more comprehensive operator interface functionality.

Concurrent Engineering needs both: a series of measurement criteria that are distinct to each process, and a set of metrics to check (and validate) the outcome when two or more of the processes are overlapped or required to be executed in parallel. Since product realization involves concurrent processes that occur across multiple disciplines and organizations, appropriate metrics and the methods of qualifying them are essential. The paper describes these life-cycle measures and metrics and how those could be used for gaining operational excellence.

The autoignition delay time and location of a n-heptane fueled high pressure and high temperature spray combustion chamber under Diesel engine conditions has been investigated numerically. The conservation equations for the fluid dynamics of sprays have been solved using the KIVA-II code with its standard spray models. A detailed chemical mechanism of 81 elementary reactions and 37 chemical species has been applied to describe the ignition and combustion of n-heptane. The coupling between complex chemistry and turbulence is treated by employing the Representative Interactive Flamelet (RIF) concept. Unsteady flamelets are computed using a separate flamelet code that interacts with the CFD solver at each time step. The scalar dissipation rate, which is an important parameter for the flamelet, has been studied numerically under different conditions.

Steady-state temperature measurements were made at two locations on the back surface of the intake valves of one of the cylinders of a Saturn 1.9-L DOHC engine. The temperature locations were such that in the upstream location the thermocouple is subjected to the impingement of the fuel spray during the injection process, whereas in the downstream location the thermocouple is out of the main fuel spray. The measured intake valve temperature at the upstream location was significantly lower than that at the downstream location, which was attributed to the spray cooling effect. The intake valve temperature was found to increase with increasing load, speed and coolant temperature. As the air-fuel ratio changes the valve temperature exhibits a maximum at near stoichiometric compositions, which is attributed to convective heat transfer from the backflow of combustion gases during the valve-overlap period.

The restraint usage and seating location of children in crash-involved passenger cars were estimated using National Accident Sampling System (NASS) data. Whether drivers of cars were restrained or not appears to play a dominant role in whether child passengers were likewise restrained or not. Most infant passengers were restrained irrespective of driver restraint usage. In contrast, the restraint usage of older children was dramatically influenced by the driver's restraint usage. If the driver was restrained, restraint usage by children dropped only slightly. If, however, the driver was unrestrained, restraint usage by children dropped by an order of magnitude This precipitous drop in restraint usage appears to have occurred by the age of five or six. Thereafter, the restraint usage of children riding with unrestrained drivers remained low and relatively constant.

The Space Shuttle Lightweight Mission Specialist Seat (LWS-MS) is a crew seat used by mission specialists who fly aboard the Space Shuttle. A team of NASA and Lockheed-Martin engineers from the Johnson Space Center (JSC) in Houston, Texas, redesigned the MS seats and reduced the weight of the seats by 52%. In addition to weight reduction, the seats were designed to tolerate stringent load conditions, inspired by new FAA regulations requiring new seats to undergo dynamic testing and floor warping demonstrations. This paper describes the analysis methods used to predict the behavior of the seat. Detailed finite element models, developed using MSC/NASTRAN, and dynamic models using finite element and rigid-body information combined in a program called DADS, were used to accurately characterize the behavior of the seat before testing even began. This analysis technique led to significant weight reductions, as well as safety improvements in the seat.

Experimental investigations relating to the performance and emission characteristics under idling conditions of a three cylinder passenger car spark ignition engine operating on a conventional carburettor and a developed single point gasoline fuel injection system are described in this paper. The idling performance at different engine speeds was studied by carrying out comprehensive engine testing on a test bed in two phases. In the first phase, experiments were conducted on an engine fitted with a conventional carburettor whilst they were extended to the engine provided with a developed electronic single point fuel injection (SPI) system, whose fuel spray was directed against the direction of air flow. The injection timing of the SPI system was varied from 82 deg. before inlet valve opening (or 98 deg. before top dead center) to 42 deg. after inlet valve opening (or 26 deg. after top dead center).

Uncertainty about future costs and operating attributes of electric drive vehicles (EVs and HEVs) has contributed to considerable debate regarding the market viability of such vehicles. One way to deal with such uncertainty, common to most emerging technologies, is to pool the judgments of experts in the field. Data from a two-stage Delphi study are used to project the future costs and operating characteristics of electric drive vehicles. The experts projected basic vehicle characteristics for EVs and HEVs for the period 2000-2020. They projected the mean EV range at 179 km in 2000, 270 km in 2010, and 358 km in 2020. The mean HEV range on battery power was projected as 145 km in 2000, 212 km in 2010, and 244 km in 2020. Experts' opinions on 10 battery technologies are analyzed and characteristics of initial battery packs for the mean power requirements are presented.