Sunday, February 26, 2012

Tolga ASA_030070177_1stWeek


1.     Opitz System (Classification)


The Opitz System: The Opitz Coding system is probably the best known coding system. This code uses a hybrid code structure. However, except for the first digit, it resembles a chain structure more closely.
The Opitz form code uses five digitsi representing (1) component class, (2) basic shape, (3) rotational-surface machining, (4) plane-surface machining, and (5) auxilary holes, gear teeth and forming. Primary, secondary, and auxilary shapes can be represented using the five geometric digits.
(Computer Aided Manufacturing Second Edition, Chang T.C., Wysk R.A, Wang H., 1998, Pages: 485,486)

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Opitz System
The Opitz code is a nine-digit coding system that uses a geometirc code for first five digits and a supplementary code for the last four digits. The can can be used to classify rotational or non-rotational parts. Rotational parts are classified by their lenght/diameter ratio and non-rotational parts are classified by their lenght/width and lengthheight ratios.
The first five digits of the Opitz code represent:  (1) part class, (2) external shape, external shape elements, (3) internal shape, internal shape elements, (4) plane surface machining, and (5) auxiliary holes and gear teeth. The last four digits represent (1) diameter d or edge lenght A, (2) material, (3) initial form, and (4) diameter D or edge lenght A (Accuracy)
(Computerized manufacturing process planning systems, Hong-Chao Zhang,Leo Alting, p. 97)

2.     Outsourcing (Logistic)


Outsourcing:
Outsourcing has been an issue of major attention, notably in the popular media. Undoubtedly, it will continue to be a significant concern. Low labor costs (such as those in China, India, Mexico, and Pacific Rim countries) can be countered effectively, in the West and in the Japan by improving productivity, reducing the labor component of products, and further improving the efficiency and manufacturing operations. The economic justification for outsourcing is complex and controversial.
(Kalpakjian, S., Schmid, S. R., Manufacturing Engineering and Technology, 5th ed., p. 1264)

New Answer (better)

Outsourcing is the act of transferring some of an organization’s recurring internal activities and decision rights to outside providers, as set forth in a contract. Because the activities are recurring and a contract is used, out-sourcing goes beyond the use of consultants. As a matter of practice, not only are the activities transferred, but the factors of production and decision rights often are, too. Factors of production are the resources that make the activities occur and include people, facilities, equipment, technology, and other assets. Decision right are the responsibilities for making decisions over certain elements of the activities transferred.
(Strategic outsourcing: a structured approach to outsourcing decisions and initiatives, Maurice F. Greaver, p. 3)

3.     Soliform System (Manufacturing )


Soliform Systems (better)
The Soliform creates models from photo-curable resins. The resin developed by Teijin is an acrylic - urethane resin with a viscosity of 40 000 centapoise and a flexural modulus of 52.3 MPa as compared to 9.6 MPa for a grade used to produce conventional prototype models. The properties of the resin and the accuracy of the laser beam are considered more significant.
The Soliform has been used in many areas, such as injection molding (low cost die), vacuum molding, casting and lost wax molding.
Teijin Seiki Co. Ltd., originally founded in 1994, is a diversified industrial components. Its Soliform system is based on the SOMOS (Solid Modeling System) laser curing process developed by Du Pont Imaging Systems. The company acquired exclusive Asian rights to the equipment aspects of this technoloy in 1991 under its Solid Imaging Department, with its first machine shipped in 1992. Since 2001, Teijin Seiki has merged with CMET Inc. under one umbrella. The CMET's company address is Kamata Tsukimura Building, 5-15-8, Kamata, Ohta-cu, Tokyo 144-0052, Japan.
Teijin Seiki Co. Ltd. produces two main series (250 and 500 series) of the Soliform system.
The Soliform system has several technological advantages:
1. Fast and accurate scanning.
2. Good accuracy.
3. Photo resins.
The Soliform system has the following disadvantages:
1. Requires support structures.
2. Requires post - processing.
3. Requires post - curing.
The soliform system contains the following hardware: a SUN-EWS workstation, an argon ion laser, a controller, a scanner to control the laser trace of scanning and a tank which contains the photopolymer resin.
(Chua C. K, Leong K. F and Lim C. S, Rapid Prototyping - Principles and Applications, Second Edition, p. 74-77)

New Answer

Teijin Seiki’s Soliform
The Soliform creates models from photo-curable resins based essentially on the princibles described in SLA. The resin developed by Teijin is an acrylic-urethane resin with a viscosity of 40 000 centipoise and a flexural modulus of 52.3 Mpa, compared to 9.6 Mpa for a grade used to produce conventiondal prototype models.
Parameters that influence performance and function are generally similar to the SLA, but for Soliform, the properties of the resin and the accuracy of the laser beam are considered more significant.
(Computer Aided and Integrated Manufacturing Systems: Optimization methods, Cornelius T. Leondes, p. 169)

4.     Three Dimensional Printing (Manufacturing )


Three-Dimensional Printing: 24.03.2011 00.40
This RP technology was developed at Massachusetts In­stitute of Technology. Three-dimensional printing (3DP) builds the part in the usual layer-by-layer fashion using an ink-jet printer to eject an adhesive bonding material onto successive layers of powders. The binder is deposited in areas corresponding to the cross sections of the solid part, as determined by slicing the CAD geometric model into lay­ers. The binder holds the powders together to form the solid part, while the unbonded powders remain loose to be removed later. While the loose powders are in place during the build process, they provide support for overhanging and fragile features of the part. When the build process is completed, the part is heat treated to strengthen the bonding, followed by removal of the loose powders, To further strengthen the part, a sintering step can be applied to bond the individual powders.
The part is built on a platform whose level is controlled by a piston. A layer of powder is spread on the existing part-in-process. An ink-jet printing head moves across the surface, ejecting droplets of binder on those regions that are to become the solid part. When the printing of the current layer is completed, the piston lowers the platform for the next layer.
(Mikell P. Groover,Fundamentals of Modern Manufacturing,4th Edition,pg.793)

New Answer (better)

Three dimensional printing(3DP) is a highly versatile additive fabrication process involving the repeated deposition and selective binding of powder layers using a printhead-deposited liquid. The unbound powder remains in the print bed throught the printing process and supports the creation of overhangs and internal features that may not be possible through other fabrication methods. 3DP is one of a number of manufactoring processes in the larger field of Rapid Protyping. (RP). But is unique amongst the various RP systems in its inherent flexibility. One of the major benefits of 3DP is the considerable variety in material selection since any material that can be deposited as a powder provides a good candidate for 3DP fabrication. 3D printin of metals and ceramics is particularly successful since powder processinf of such materials is well understood, but almost any material is printable given the various processing options available to create powders with depositable particle sizes.
(Development and application of new material systems for three dimensional printing, Ben Utela,University of Washington, p. 1)

5.     Paper Lamination Technology (Manufacturing )

 


Paper Lamination Technology (PLT)

This technique is a variation on LOM and was developed by Kira Corporation. Paper Lamination Technology (PLT) uses a knife to cut each layer instead of a laser and applies adhesive to bond layers using the xerographic process. The Paper Lamination Technology (PLT) uses an additive/subtractive process by which layers of paper (for use with copy machine) are bonded together by high heat and pressure and then uses computerised cutter to cut to desired profiles. Similar to the LOM technology, the part does not go through a phrase change. Products are made by paper lamination as follows:
Paper Feed Unit: A sheet feed mechanism orients the one sheet on the target block.
Hot Press System: Using high pressure, the hot press moves the target block with sheet up a hot plate. All the area of the sheet is applied adheres to the target block. The amount of movement up to the hot plate is measured. If deviation in sheet and resin thickness is identified, automatic compensation is made to insure dimensional integrity of the completed 3D model.
Cutting Process: The PC generates plotting data based on section data of the target shape. A mechanical cutter cuts the top layer of the target block along the contour of the section.
Processes are repeated rapidly and accurately. Unnecessary partions are removed.
 (Miltiadis A. Boboulos; CAD-CAM & Rapid Prototyping Application Evaluation; Page: 157,158)

New Answer (better)
Manufacturing (SSM) by Beijing Yinhua, Chna, (b) Zippy RP Systems by Kinergy PTE Ltd., Singapore; and (c) Paper Lamination Technology (PLT) by Kira Corp. Ltd., Japan. The PLT system makes use of plain paper (no adhesive) as the build material, and a laser printer is used to apply a proprietary resin powder on top of the previosly deposited layer or subsrate in the regions where bonding is desired. Because the support material is not adhesively bonded, unlike in LOM, the support removal process is easier.
(Additive Manufacturing Technologies: Rapid Prototyping to Direct Digital Manufacturing,  Ian Gibson,David W. Rosen, p.  209)

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