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)
New Answer (better)
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
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
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
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
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.
New Answer
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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