The essential role of tool management is the timely
scheduling of tools to satisfy a short to medium term
man-ring task. The heart of a typical tool
management system is the tool list which is derived
from the machining schedule, the starting point and
controlling factor of all the cells’ activities and events.
The machining schedule or list, at the highest level,
consists of or&r numbers, due dates, priorities and
required quantities. The machining list may be
subdivided into partial orders (individual workpieces)
and stored in the form of or&r waiting queues or work
schedules. These schedules exist for every machine in
the cell, and specify the sequence of operations for a
particular wrkpiece, and the required tool sequence
(the tool list). The tool lists not only determine the
schedules for tool transfer and tool changing but also
the gross tool requirement. A net tool requirement is
established by examining tool store contents for the
appropriate tools which have adequate residual tool
life; and introducing new tools where necessary, to
service the machining schedule. The generated tooling
requirement is placed in the tool room, which is
responsible for supplying the required tools. The
organization of the tool rwm to manage these required
tools depends upon the facilities supplied and the
manpower used. As orders are being processed, the
currently completed number of workpieces is recorded
and updated. The consequences of these completed
vvorkpieces on the lists is an indication of which tools
are no longer required or can no longer be used due to
reaching their life limit. This in turn activates the tool
transfer schedule and new tools may be introduced into
the system.
(
Part and tool flow management in multi-cell flexible manufacturing system, Mustafa Özbayrak,A. Kürşad Türker, 1997, Page: 810
)
Tool Management (old)
Tool Management: Tool Management is a vital activity that is frequently neglected by the manufacturing engineer. It deals with tracking of tool location, cutting elapsed time, times for reconditioning, and so on. Minimizing tool breakage is a critical task of this control module.
(Computer Aided Manufacturing Second Edition, Chang T.C., Wysk R.A, Wang H., 1998, Page: 8)
2- Component reuse (new-better)
Component reuse techniques have been a recent focus of research because they are seen as the
next-generation techniques to handle increasing system complexities. However, there are several
unresolved issues to be addressed and prominent among them is the issue of component matching.
As the number of reusable components in a component database grows, the task of manually
matching a component to the user requirements becomes infeasible. Automating this matching
can help in rapid system prototyping, improving quality and reducing cost. In addition, if the
matching algorithm is sound, this approach can also reduce precious validation effort.
(Forced simulation: A technique for automating component reuse in embedded systems
Partha S. Roop, A. Sowmya, S. Ramesh, 2001, page: 602)
Component Reuse (old)
Taking time and money to create a low-cost component maybe of value to other teams designing similar products. In general, this value is not explicitly accounted for in manufaturing cost estimates. The team may choose to take an action that is actualy more costly for their product because of the positive cost implications for other projects.
(Kalpakjian S., Schmid S.R.,Manufacturing Engineering and Technology, 5th Edition, pg.229)
3- Casting terminology (new-better) (manufacturing method)
Before we proceed to the process fundamentals, it is helpful to first become familiar with a bit of casting vocabulary. Figure 11-2 shows a two-part mold, its cross section,
and a variety of features or components that are presented in a typical casting process. To
produce a casting, we begin by constructing a pattern, an approximate duplicate of the final casting. Molding material will then be paked around the pattern and the pattern is
removed to create all or part of the mold cavity. The rigid metal or wood frame that
holds the molding aggregate is called a flask. In a horizontally parted two-part mold,
the top half of the pattern, flask, mold, or core is called the cope.The bottom half of any
of these features is called the drag. A core is a sand (or metal) shape that is inserted into
a mold to produce the internal features of a casting, such as holes or passages. Cores are
produced in wood, metal or plastic tooling, known as core boxes. A core print is a fea-
ture that is added to a pattern, core, or mold and is used to locate and support a core
within the mold. The mold material and the cores then combine to produce a completed
mold cavity, a shaped hole into which the molten metal is poured and solidified to pro-
duce the desired casting. A riser is an additional void in the mold that also fills with
molten metal. Its purpose is to provide a reservoir of additional liquid that can flow into
the mold cavity to compensate for any shrinkage that occurs during solidification. By
designing so the riser contains the last material to solidify, shrinkage voids should be
located in the riser and not the final casting.
The network of connected channels used to deliver the molten metal to the mold
cavity is known as the gating system. The pouring cup (or pouring basin) is the portion
of the gating system that receives the molten metal from the pouring vessel and controls
its delivery to the rest of the mold. From the pouring cup, the metal travels down a sprue
(the vertical portion of the gating system), then along horizontal channels, called
runners, and finally through controlled entrances, or gates, into the mold cavity. Addi-
tional channels, known as vents, may be included in a mold or core to provide an escape
for the gases that are originally present in the mold or are generated during the pour.
The parting line or parting surface is the interface that separates the cope and drag
halves of a mold, flask, or pattern and also the halves of a core in some core-making
procees. Drat is the term used to describe the taper on a pattern or casting that per-
mits it to be withdrawn from the mold. The draft usually expands toward the parting
line. Finally, the term casting is used to describe both the proceess and the product when
molten metal is poured and solidified in a mold.
(Degarmo's Materials and Processes in Manufacturing, E. Paul DeGarmo, J. T. Black, Ronald A. Kohser, 2011, page: 270-271)
Casting terminology (old)
The casting starts with the construction of a pattern, an approximate duplicate of the final casting. The modeling material is then packed around the pattern, and the pattern is removed to produce a mold cavity. The flask is the box that contains the molding aggregate. In a two-part mold, the cope is the top half of the pattern, flask , mold or core. The drag is the bottom half of any of these features. A core is a sand shape that is inserted into the mold to produce internal features on a casting , such as holes or passages for water cooling. A core print is the region added to the pattern, core or mold that is used to locate and support the core within the mold. The mold material and the core then combine to form the mold cavity, the void into which the molten metal will be poured and solidified to produce the desired casting .A riser is an extra void created in the mold that will be filled with molten metal. It provides a reservoir of molten metal that can flow into the mold cavity to compensate for any material shrinkage that occurs during solidification. Any shrinkage voids should then be in the riser and not in the final casting.
(MATERIALS AND PROCESSES IN MANUFACTURING 7th edition E.PAUL DEGARMO P.309)
4- Unisurf (new-better) (computerized system)
In the middle of the l960’s. a system for designing and manufacturing cars
using free-form curves and surfaces was developed by P. Bézier at the Renault
automobile company. This computerized system, named UNISURF, provides
a general mathematical framework for defining arbitrarily shaped curves and
surfaces.
UNISURF proved to be a highly successful system. The essence of its success
was that it combined modern approximation theory and geometry in a way that
provides the designers with computerized analogs of their conventional design
and drafting tools. Due to his great contribution to the newly established branch of
applied mathematics and computer science known as computer-aided geometric
design. Professor Bézier has been recognized widely as one of the pioneers in this
field. 'l‘he curve and surface definitions which his UNISURF system popularized
have come to be known as Bézier curves and surfaces. Bézier curves are available
in most current drawing programs.
(Over and Over Again, Gengzhe Chang, Thomas W. Sederberg, 1997, page: 176)
UNISURF(old)
In the middle of 1960s a system for designing and manufacturing cars using free form curves and surfaces was developed by P.Bezier at the Renault automabile company This computerized system named UNISUF, provides a genreral mathematical framework for defining arbitarily shaped curves and surfaces.
Gengzhe Chang,Thomas W. Sederberg, Over and Over Again, P.176
5- Euro Emission Standarts(new-better)
Vehicle emission limits for NO,“ C0 and particulate matter have been made more
stringent, in line with EU requirements (Table 2.10). Emissions are regulated by the EU
for most vehicle types, including cars, lorries, buses, trains, tractors, barges, excluding
seagoing ships and airplanes. ln 1996 Euro 2 introduced different emission limits for
diesel and gasoline vehicles. Diesels have more stringent C0 standards but are allowed
higher NO, emissions. Gasoline-powered vehicles are exempt from particulate matter
standards, but vehicles with direct injection engines will be subject to a limit of
0.005 g/km for Euro 5 and Euro 6. Euro 5 and Euro 6 standards for passenger cars,
which will come into force on 1 September 2009 and I September 20l4, emphasise
further reductions of emissions of particulates and N0," especially for diesel vehicles.
With regard to heavy-duly vehicles, Euro III. IV and V standards include voluntary,
stricter emission limits for extra low emission vehicles, known as “enhanced
environmentally friendly vehicles” (EEVs). In December 2008, the Commission’s
proposed Euro VI standards were agreed upon, which will become effective from 2013
and are closer in stringency to the US 2010 standards.
OECD environmental performance reviews:Finland, Organisation for Economic Co-operation and Development, 2009,page: 47) |
Euro Emission Standarts
The European Union is introducing stricter limits on pollutant emissions from light road vehicles, particularly for emissions of nitrogen particulates and oxides. The Regulation also includes measures concerning access to information on vehicles and their components and the possibility of introducing tax incentives.
In order to limit pollution caused by road vehicles, this Regulation introduces common requirements for emissions from motor vehicles and their specific replacement parts (Euro 5 and Euro 6 standards). It also lays down measures improving access to information on vehicle repairs and promoting the rapid production of vehicles in compliance with the provisions of the Regulation.
Regulation (EC) No 715/2007 of the European Parliament
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