1)Spin Forming (old)
In this sheet metal forming process , a sheet metal disk is rotated in a special type of lathe tool , while a special forming tool is pressed against the rotating disk of metal in a rotary swaging operation , thus forming or spin drawing the part to the required shape against ist forming pattern. The process is limited to metal sections which are of a symemetrical , rotated section , such as bell shapes , cones parabolic sections and cylinders
(Electromechanical design handbook ; Ronald A. Walsh ,pg .12 3rd edition)
Spin forming (new-better) (manufacturing method)
Spinning involves forming sheet metal or tub-
ing into seamless, circular shapes (hollow cylin-
ders, hemispheres, cones, domes, etc.) by a
combination of rotation and force. The forming
can be done by either manual spinning or by
power spinning. Manual spinning results in no
appreciable thinning and involves relatively lit-
tle force. It is normally done on a lathe and con-
sists of pressing a spinning tool against a circu-
lar sheet (blank) that is forced against a shaped
mandrel. which is attached to and rotated by the
headstock. The workpiece is clamped to the
mandrel by a follower block that is attached to
the tail stock. Two spinning setups are illustrated
in Fig. 20.27 . Simple shapes.
where dimensional tolerances are not critical.
may not require a mandrel. In
power (shear) spinning. the metal is intentionally
thinned by shear forces. Spin forming can gen-
erally be performed without heating the metal.
Exceptions are for metals having low dttctilities.
such as beryllium. and for large-thickness blanks
used with power spinning. Because of low tool-
ing costs. manual spinning is often used for
prototype runs and for relatively small produc-
tion runs.
(Beryllium chemistry and processing, Kenneth A. Walsh, 2009, page:327)
2)pallets: (old)
pallets and pallet systems have greatly increased the number of individual parts that can be machined.
these systems, while widely used with newer machining centers,are available for older centers as well.the
two major forms of pallet system are manual and automatic.
manual pallet systems usually reauire the machine operator to perform the pallet chanchover.automatic
pallet systems conversely work in conjunction with the machine tool,which loads and unloads them automatically.in either case the use of pallets has greatly reduced the time required to change from one operation to the other.
( Edward G. Hoffman,Jig and fixture design,p.313)
Pallets (new better) (method of supporting a unit load)
The most common method of supporting a unit load is with the use of a pallet.
Pallets have provided a useful service in industry since fork trucks were developed.
They have withstood the test of time and allow for ease and eflicient movement
of unit loads by forklift trucks. Pallets are produced in various materials, sizes,
and designs. The most common materials include wood, corrugated paper, plastic,
steel, and aluminum.
Pallets provide a useful fimction in many material handling systems, but there
are many issues to consider. When considering the use of pallets, one should be
aware of the following concerns:
* Pallets can be costly. The prices depend on the vendor, type of material, design, time of year,
and quantity purchased.
* Unless pallets are only used internally getting them returned once they are
shipped is sometimes diflicult.
* Pallets are hard to clean and hard to keep clean.
* Pallets provide an excellent harbor for insects and rodents.
* Most pallets are made of flammable materials and present a potential fire
hazard when in storage.
* Pallets take up space that could be used for product in the warehouse and in transit.
* Empty pallets take up warehouse space.
* Damage to pallets can cause product damage and unstable loads.
* Repair and maintenance of pallets can be costly.
* Pallets add extra weight to pallet stacks and product shipment.
(Warehouse Management Handbook, James A. Tompkins, Jerry D. Smith, 1998, page:776)
3)Laser Additive Manufacturing:(old-better)
The laser additive manufacturing process (LAMP) is a large scale manufacturing capabilty developed and operated in AeroMet Corporation in Eden Prairie, MN. The LAMP process uses a laser to sinter deposited titanium powder much like the LENS and POM processes. The key difference with LAMP is the high deposition capability and large working envelope: the system deposites 10 to 12 pounds of metal per minute, at a 95% or better powder usage rate, and has an expandable working area of a minimum 4'x4'x4'. The laser system is very large, and the laser beam is actually piped in through a wall using fiber optic tubing. LAMP parts are typically built with about 0.050" tolerances, which are then final machined to meet dimensional requirements.
(Kenneth G. Cooper, Rapid Prototyping Technology: Selection and Application, p. 129)
The laser additive manufacturing process (LAMP) is a large scale manufacturing capabilty developed and operated in AeroMet Corporation in Eden Prairie, MN. The LAMP process uses a laser to sinter deposited titanium powder much like the LENS and POM processes. The key difference with LAMP is the high deposition capability and large working envelope: the system deposites 10 to 12 pounds of metal per minute, at a 95% or better powder usage rate, and has an expandable working area of a minimum 4'x4'x4'. The laser system is very large, and the laser beam is actually piped in through a wall using fiber optic tubing. LAMP parts are typically built with about 0.050" tolerances, which are then final machined to meet dimensional requirements.
(Kenneth G. Cooper, Rapid Prototyping Technology: Selection and Application, p. 129)
Laser Additive Manufacturing(new) (manufacturing method)
The Laser Additive Manufacturing (LAM) project. a joint Army/Air Force/DLA
project, contributed to an entirely new manufacturing process for titanium structure
fabrication. This process was recently applied to aluminum F-15 Strike Eagle pylon ribs
that were failing prematurely. Action in the Iraq war had depleted the inventory. Ship
sets made from titanium replaced the failed components in only two months and have a
life extension of five times that of aluminum, thereby significantly increasing the safety
of the structure and increasing the mission availability of the aircraft.
LAM is based on a stereo lithography approach to manufacturing. Using
software to convert a computer-aided design file to a sliced format, parts with properties
in the class of forgings are built one layer at a time, making LAM a true manufacturing-om
demand process. Cycle time is reduced by up to 80 percent: the cost of many
components is reduced by ten to 30 percent; and the process is environmentally
friendly and provides tremendous surge capability.
This project also exemplifies the “jointness" aspect of the ManTech program.
demonstrating the impact that can be realized through joint investment. The Army
lunded the development of the production system for LAM. The Air Force lunded the
refinement of the process and the development of aviation applications. The Navy
provided funding for application to F/A-18 components. DLA funding is supporting lull
qualification of weapon system applications irom all Senricss and the development oi a
next generation capability. And, finally, most of the work was cost shared by the
companies involved.
(Annual Industrial Capabilities Report to Congress, 2006, page: 46)
4)A Layered Structure(old)
A Layered Structure has been considered by many investigators. A variety of tecniques has been introduced. Among these normal incidence longitudinal waves can be applied in the low frequency regime, and the transmitted and/or reflected signals can be used for the evaluation of a layered medium. A referenced signal has to be introduced in order to calibrate the evaluation. A self-compensating tecnique has been proposed to evaluate a layered structure, in that a ratio of transmission and reflection coefficients has been used. In order to effectively deduce the parameters of a layered structure, the sensitivity of the ratio of transmission and reflection coefficients of a layered structure to variation of the parameters and the distirbution of minima in an error surface.
(Chenng A., Achenbach J. D., Rewiev of Progress in Quantitative Nondestructive Evaluation,2002,p.1815)
A Layered Structure(new-better) (operating system arrangement)
The TSB and its work environment can be described with a layered structure. As
Fig. 3 illustrates, the structure may be divided into five layers, which are Hardware
Layer, Basic Layer, Core Layer. System Layer and Application Layer respectively
from the bottom to the top. The Hardware Layer and the Application Layer represent
the work environment the TSB is in. They do not belong to the TSB in reality. The
Basic Layer and the Core Layer fall into the Kernel Space of the system, while the
System Layer and the Application Layer into the User Space.
The bottom level Hardware Layer comprises the TPCM and other hardware on the
computing platform. They provide hardware support to trusted execution of the TSB.
The top level Application Layer contains application programs and users. They are
targets the TSB is planed to support. The TSB provides them with support of trusted
functions.
The TSB is located in the Basic Layer, Core Layer and System Layer. The TSB
components in the Basic Layer are the Primary Trust Base and the Trusted Hardware
Abstraction. The Trusted Hardware Abstraction instructs the TPCM and other trusted
hardware to work. It presents convenient methods for higher layer software to exploit
trusted hardware functions by masking manufacturer-related operation details of
trusted hardware. The TSB components in the Core Layer are the Baseline Reposi-
tory, Control Mechanism, Measurement Mechanism, Decision Mechanism and Un-
derpinning Mechanism. The TSB components in the System Layer are presented in
the styles of TSB Library Routine (TSBLR), TSB System Utility (TSBSU) and TSB
Graphic User Interface (TSBGUI).
The TSB software lives across the Kernel Space and the User Space. The TSB
components in these different spaces are connected by TSB System Call (TSBSC).
TSBSC also links application programs to trusted functions given by the TSB compo-
nents in the Kernel Space.
Trust support functions offered by the TSB software and the TPCM hardware are
transferred to the System Layer via TSBSC interface by the TSB Underpinning
Mechanism. They are further presented to users and application programs by the TSB
components in the System Layer. Users usually enjoy TSB trust support functions
through application programs. They may also utilize TSB trust support functions
through TSBSU or TSBGUI. They can administer and maintain the TSB through
TSBGUI as well. Application programs may obtain TSB trust support functions by
calling TSBSC or TSBLR. In addition, they can obtain TSB trust support functions by
using TSBSU.
(Trusted Systems:
First International Conference, INTRUST 2009, Beijing, China, December 17-19, 2009. Proceedings, Liqun Chen, page: 11,12 )
5)Artificial Aging(old)
(Donald R. Askeland, The Science and Engineering of Materials, p.307-308)
Artificial Aging(new-better) (heat treatment)
Artificial aging practiees are again chosen based on the
specific alloy and desired set of final properties. but the typical
range of aging temperattmes is from 121°C-204°C (250°F-400°?)
for times of a few minutes to 24 hours. The purpose of artificial
aging is to funher precipitate alloying elements from solid
solutionandalso inereasethesizeofthe preeipitatessotbatthey
may become more effective strengtheners. when the alloy has
been exposed to the combination of aging time and temperature
that produces the maximum level of properties, the alloy is said
to be peak aged and is designated with the Aluminum
Association temper designation of “-T6”. (ln the ease of an alloy
which has had a deformation treatment between the quench and
age, the corresponding peak aged temper designation is “-T8”.)
For some alloys, further aging beyond peak aging is desirable to
improve the combination of pmperties, for example when high
levels of corrosion resistance arc desired for the 7XXX alloys or
improved ductility and stability during elevated temperanue
service are desired for aluminum alloy castings. Further aflng
beyond the peak-aged condition is termed over-aging and the
Aluminum Association temper designation for an overaged
temper is ''-T7''.
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