Mechanical Engineering Commons^™

Additive Metal Deposition Feedback Optimization For The 3d Hybrid Metal Printer, Andrew James Wyman

Dissertations

In the additive manufacturing realm, explicitly the direct energy deposition method, there continues to be numerous advancements along with advantages to control print quality of the component and the ability to apply the successful repetition of metallic layers consecutively. Metal additive printed components have the capacity to directly use the component for the desired application or intended purpose from which the three-dimensional model was created. In contrast, plastic printers that produce components that would not hold to the physical conditions required such as a metallic component could withstand.

Research exertions were focused on improving the present Western Michigan University patented …

Advancing The Use Of Quality Control Tools For High-Density Data In Modern Manufacturing, Romina Dastoorian

Dissertations

In modern manufacturing, advanced metrology systems are continually being incorporated into quality control (QC) systems to provide high-density (HD) datasets. These datasets can contain millions of measurements that can be used to represent a part’s whole geometry. While integrating HD datasets into QC systems has brought several opportunities to enhance the performance of QC systems, it has resulted in new challenges in this area as well. While significant amounts of research have been performed in this area, the QC research community still strives to tackle these challenges. This study identifies key challenges regarding incorporating HD datasets into QC systems. Specifically, …

Development Of A Finite Element Model Of The Stamping Process To Predict The Natural Frequencies Of Dimpled Beams, Varad Vasudeo Pendse

Masters Theses

Creating dimples on beams has been proven to be an effective way of altering their vibrational behavior. The objective of this research is to simulate the process of stamping using the finite element (FE) method to create a model of a dimpled beam. This dimple has non-uniform thickness, so it shows close agreement with its real-life counterpart.

ANSYS® Parametric Design Language (APDL) is used to build a three-dimensional (3-D) finite element model and simulate the process of stamping used to create the dimple. The structural simulation is validated by calculating the thickness and width of the deformed geometry of the …

A Framework Towards Technology Creation In Africa: Focusing On Ghana, Martin Yao Donani, Hannatu Abue Kugblenu, Azindow Bawa Fuseini

International Journal of African Development

Underdevelopment in Africa has been historical and a global concern coupled with the quest for good governance. Several efforts have been made in academia, national governments, the international community, and other institutional arrangements to reverse the trend. These efforts however are yet to produce a lasting result as Africa is still characterized by low productivity output, poverty and a widening technology gap when compared to other developing regions of the world. Conventional approaches used to address the African problem have consistently been devoid of indigenous technology development. Technology is here seen as paramount to every form of production on which …

Quality Improvement In Drilling Silicon By Using Micro Laser Assisted Drilling, Barkin Bakir

The Hilltop Review

The micro-laser assisted drilling (µ-LAD) of monocrystalline silicon (100), using a diamond cutting tool coupled with a laser, was tested in order to improve the cutting edge quality of a drilled samples. The laser beam is transmitted through an optically transparent diamond drill bit and focused precisely at the tool-workpiece interface, where the material is under high pressure induced by the diamond tool. The influence of the laser power on the quality and the inner surface finish of the drilled materials is investigated. Different laser powers were used to carry out the experiments. The experimental results indicated that the µ-LAD …

Loss On Ignition Using Infrared Heating, Benjamin J. Binoniemi

Masters Theses

The focus of this study is a proof of concept that infrared heating can be used to produce a reliable and rapid method of performing the loss on ignition test. The loss on ignition test is a foundry industry standard test that requires all moisture and volatile organic compounds be vaporized from a sample of foundry sand. The standard test as recommended by the American Foundry Society uses a muffle oven and requires nearly four hours to perform. This new concept performs the same test in approximately ten minutes. The biggest issues with the loss on ignition test are time …

Simulation Of An Intake Manifold Pre-Heater For Cold Diesel Engine Startup, Patrick K. Kreun

Masters Theses

Ensuring consistent, reliable diesel engine startups in cold temperatures is of utmost importance in a number of applications. Under extreme temperatures, the use of glow plugs is complemented by intake manifold heaters. In these, the energy released from combustion increases the intake air temperature before the air enters the main combustion chamber. Since the process also alters the stoichiometry of the fuel-air mixture at the intake ports, the preheater operation must be optimized in order to guarantee successful and reliable in-cylinder combustion during engine startups. This paper describes the development of an intake manifold model incorporating an air pre-heater for …

Development Of A Task Assignment Tool To Customize Job Descriptions And Close Person-Job Fit Gaps, Bryan W. Booker

Dissertations

Does the knowledge worker fit the job or should the job fit the knowledge worker? This research developed a methodology and a tool to customize a knowledge worker’s job design to better fit their knowledge, skills, abilities and characteristics. The research outcomes support the customization of the job design to improve person-job fit, the documentation of the customized job design as a position description, and the use of a structured person-task assignment process. The recommended task assignment process includes a job aid that uses multivariate equations to predict expected task performance. Data were collected from two knowledge worker sub-groups: lean …

A Practical Guideline For Establishing Non-Return Valve Specification And Performance Criteria, Eric W. Dawkins

Masters Theses

The non-return valve has been a standard piece of equipment in the injection molding industry since the reciprocating screw was developed. Most molders understand the role of the non-return valve in the molding process. But few understand the functional problems of the non-return valve. Because of this, the non-return valve has been considered a nuisance item for injection molders.

Wear of the non-return valve is another problem that molders are faced with. The factors contributing toward wear are not entirely understood. Material, temperatures, hours and machine size, etc., all effect the life of a valve. Consequently, most worn valves are …

Development Of A Statistical Model For Process Control To Eliminate Sink Marks In Injection Molded Products, Kurt Frederick Hayden

Masters Theses

Customer demands for high-quality, defect-free injection-molded products are ever increasing. In order to satisfy these quality requirements, much effort is spent monitoring and controlling variable data such as cycle time, part weight, and dimensions. Attribute defects such as sink or splay are often overlooked in the development of process control systems. However, customers reject products because of these attribute defects. Industrial control systems based upon process variables and product design variables can detect conditions that may result in the molding of products with attribute defects. The systems can then correct the process prior to the molding of these defective products. …

Comparing Refractory Coatings On Shell Sand Utilizing Elevated Temperature And Collapsibility Testing, Suet Fong Cheah

Masters Theses

This research study examines the effects of refractory coatings on a shell sand using laboratory testing equipment as opposed to the more laborious and time consuming processes of molding, melting, filling, shakeout, and obtaining dimensions of actual castings. As of today, there have not been any such laboratory test methods. This research project focused on quantifying distortion, mass change, and impact strength found in refractory coated shell sand. The equipment used was the thermal distortion tester (TDT) and a modified impact tester. The thermal distortion curves (TDC), mass change, and impact strength are provided and compared for all systems studied. …

Using Stiffeners For Improved Geometric Fidelity Of Flexible Elements, Ankit Kapoor

Masters Theses

Flexible hoses play an important role in safe operation of a transportation vehicle in automotive and aerospace field. Due to lack of accurate and efficient modeling techniques for such flexible elements with large deformation, most Computer Aided Engineering system do not address the problem in their solution methods.

In this thesis a method is presented to improve the geometric fidelity of flexible element models by using off-axis bi-linear stiffeners (spring) into a discrete linear beam model. Resulting deflection of a hose were compared with the digital scans of an actual deflection of the hose. Though the method is computationally expensive, …

A Study Of Kanban Based Production System In Cellular Manufacturing Environment, Sanjay Bhargava

Masters Theses

The study of effects of production data variabilities on Kanban based cellular manufacturing system is vital before its design and implementation because it would give better understanding of their uncertain behavior.

In this research, a detailed analysis of a Kanban system, with subcell scenario, under dynamic operating conditions is performed. The Control variables considered were number of Kanbans, processing time variability, demand variability and machine breakdown. The performance parameters considered were profit, production lead time, machine utilization and material processing lead time.

Approximately 200 simulation runs were made with 3 replications each by varying one control variable at a time. …

An Empirical Study Of Just-In-Time And Total Quality Management Principles Implementation In Manufacturing Firms In The U.S., Loknath Sriparavastu

Masters Theses

Literature in vogue points out that, in the last decade, American manufacturing companies came a long way in their renewed emphasis on the quality process. Justin- Time (JIT) and Total Quality Management (TQM) are the two magical phrases that are being frequently used in almost all the articles published on quality and productivity. Nevertheless, the literature does not provide any satisfactory explanation as to how JIT and TQM principles are implemented in the manufacturing industries.

This research, through a nationwide empirical survey, analyzed the effects of JIT and TQM strategies implementation. Survey results showed that implementing both JIT and TQM …

An Empirical Investigation Of Quality And Productivity Management Practices In Manufacturing Firms, Kiran Vuppalapati

Masters Theses

A growing number of firms are implementing the concept of Just In Time (JlT) manufacturing and Total Quality Management (TQM). This research examines the impact of these management philosophies in manufacturing firms.

This research identifies a set of critical organizational variables necessary for a successful . implementation and the organizational problems faced during their implementation. The major object is to test the performance of firms implementing both JlT and TQM against firms implementing none of these philosophies. Results show that JIT-TQM firms are more customer focused and have better employee relations than traditional firms. This study also compares the performance …

An Experimental Study Into The Role Of Routing Flexibility In The Justification Of Advanced Manufacturing Systems, Sanjay Pathak

Masters Theses

Increased competition in manufacturing has focused attention on advanced technologies. These costly technologies lead to difficulty in purchase justification using traditional methods. New methods quantify attributes relating to the flexibility of advanced systems. One such attribute is routing flexibility.

This thesis presents results of experiments into evaluation of routing flexibility. The performance of conventional dedicated machinery when compared with that of machines having routing flexibility indicates an advantage of flexible machinery. The thesis indicates a procedure for evaluation of different flexibilities and their comparison with conventional machinery in reality.

An empirical formula is developed that helps in quantifying routing flexibility …