2. For example, in the science of thermodynamics, the concept
of work, energy, and thermal efficiency are clearly defined (using
mathematics) and the relationships between variables and processes
are governed by laws and principles. From Carnot's principle, a
theoretical maximum thermal efficiency can be calculated for any
heat engine operating between two heat reservoirs. As a result of
this limiting condition, the efficiency of many common power
producing devices is based not on an absolute scale but instead
relative to the Carnot efficiency. Advances in technology may
enable engineers to design products which approach the Carnot
efficiency, but the limit will not be exceeded.
In manufacturing, it might also be possible to calculate
optimum theoretical efficiency. However the number of variables
associated with machining a complex part through a series of
operations would make such an analysis extremely difficult and
involve so many uncertainties that any calculated limit would be
virtually meaningless. Manufacturing processes are a combination
of science, technology, and the creativity of the manufacturing
engineer. For this reason, manufacturing is a very dynamic,
exciting, and sometimes unpredictable field.
When analyzing a manufacturing problem and planning
solutions, a few basic principles must be recognized. These
principles are:
• the variables are usually dependent, not independent;
• there is no such thing as unlimited resources -- including time;
• problem definition is always the first step in problem solving;
• there is always a decision, although it may be to do nothing;
• inertia exists in people's minds as well as in physical objects;
• knowledge without communication is valueless;
• miracles may in fact be possible, but are not probable.
These are a few of the basic principles we all know, but all
too often they remain in our subconscious when we develop a
strategy for improvement. Recognizing this, we went back to these
basic principles to develop theorems around which to design and
build our manufacturing strategic plan.
I will touch on a few of these theorems beginning with
problem definition. Consistent with conventional wisdom, we
decided our objective was to improve quality, cost, and delivery. In
deciding how to do this, however, we recognized that these
characteristics are dependent variables that traditionally were
attacked independently. What we needed to manage and improve
was the total, not the individual elements. This seemingly simple
conclusion was a major break-through in our thinking because it
explained many of the physical and organizational roadblocks we
experienced in the past. We recognized that we had become experts
at improving specific elements, but that in manufacturing, the sum
of the elemental gain independently derived will not necessarily
produce the optimum result. This simple realization led us to a
conclusion that group technology, in its broadest terms, would be
the primary concept applied in developing our strategic plan.
Another basic theorem that we formulated our plan around
is: concept selection is important, technology used is interesting,
but implementation is absolutely critical. Based on this theorem, we
decided to use predominantly existing technology and not push the
state-of-the-art unless absolutely necessary. This allowed us to
focus our efforts on implementation and avoid the temptation to
modify our strategy to suit each new technological advancement that
appeared on the horizon. As Sir Robert Watson Watt said, "Give
me the third best technology. The second best won't be ready in
time. The best will never be ready."
Having agreed on the principles, theorems and concepts, and
having chosen group technology as our basic framework, we began
by segregating our engine parts based on similarity of resources
required for their manufacture. One of our six manufacturing plants
or our purchasing department was designated as the source
responsible for each group of parts. We refer to part groupings for
which delivery responsibility has been designated to a particular
source as that source's "Charter Parts." We then separated the
strategic programs group into teams. One team was assigned to
each source, with core teams established to provide overall technical
support in areas such as simulation, systems, metallurgy, quality,
data acquisition, financial, etc. Each source team analyzed and
selected alternatives, prepared a proposed implementation plan,
including a schedule, and determined the magnitude and timing of
resources required for implementation. When considered
independently, the implementation of each plan was found to be
possible. However, when combined they exceeded the technical
resources available. Priorities were set for the various plans and a
combined implementation strategy and schedule was established.
This combined strategy resulted in a decision which began
with fully implementing the plans at two of the plants and segments
of the plan at the other plants. Those plans not selected for initial
implementation were fully documented, thus ensuring the overall
view for the future was not lost, and that current actions would not
preclude later implementation of these plans. This was one of the
more important lessons learned. A clear view of the end objective is
required, whether working at the macro or micro level to ensure
focus and avoid painting yourself into a corner.
The Southington plant was one of the sources selected for
full implementation and approximately 30 employees from the
strategic programs group were transferred to the plant. They, with
selected key personnel from the plant, were used to form the "core
group" for implementation which reported to the plant manager.
Southington's charter parts were to consist of disks, hubs, drum
rotors and spacers. These are rotating parts that form the heart of a
jet engine and are required to operate in a very hostile environment,
including high temperatures and stresses. This necessitates the use
of very sophisticated materials, such as titanium and nickel-based
alloys which are machined to extremely close tolerances. In addition
to providing the normal dimensional and visual characteristics, the
manufacturing processes must be consistent to ensure that the
mechanical properties of the material are not changed inadvertently.
THE SOUTHINGTON PLANT AS IT EXISTED
In order to understand the magnitude of the task at hand, it is
necessary to discuss briefly the Southington plant as it existed when
the thirty person implementation team arrived in November, 1985.
The plant employed 1100 hourly and 325 salaried personnel.
It was approximately 550,000 square feet in size and had about 400
major pieces of production equipment with an average age of 22
years. Most machines lacked such features as tool changers and
probing capability and only about 50 included numerical control or
computer numerical control. While the plant produced a number of
disks, hubs and spacers, the majority of manufacturing space was
devoted to a wide variety of parts such as gear box housings, cases,
shrouds, seals, rings and other miscellaneous parts. Although the
product mix was considerably different than what was planned for
the future, a highly skilled and experienced workforce was in place
to support the upcoming changes.
As with all Pratt & Whitney manufacturing plants at the time,
the plant used a functional organization, with equipment located by
machine type. In other words, there were turning areas, milling
areas, etc. The parts travelled from area to area around the plant,
with each area responsible only for its segment of the manufacturing
process. With this manufacturing approach, the average disk moved
approximately 3 1/2 miles during a 12 to 15 week manufacturing
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3. cycle and with operations performed by perhaps a dozen different
departments. Each area was supervised by foremen who reported to
general foremen working for area superintendents, who in turn
reported to the plant manager. Support managers of manufacturing
engineering, finance, materials, plant engineering, etc., also
reported to the plant manager. At the time, the plant also had two
main quality department areas. With a focus mainly on inspection of
the finished product, these areas were staffed and supervised as
separate entities under the quality department.
The quality assurance manager assigned to Southington
reported for both administrative and technical direction to the
manufacturing division's vice president of quality assurance, who
was located at the East Hartford, Connecticut facility. Therefore,
the quality assurance manager's operating and manpower budgets,
as well as his operating strategy, were largely established
independent of the Southington plant. Obviously, there was
communication with the plant manager, but the final decisions on
quality policy were external to the Plant.
The organizational approach, practices and procedures of the
quality department at that time resulted in an underlying culture
which suggested that the quality department was responsible for part
quality. The substantial use of final or "tail gate" inspection, while
providing tight control of out-going product quality, resulted in a
time span between origination and detection of deviations, which
made problem identification and solution, at best, difficult.
Manufacturing engineering, as a separate function, supported the
shop from a central office physically separated from the factory
floor. Processes for new parts were individually assigned to
manufacturing engineers, with each Engineer determining and
documenting the process required, including the issuance of tooling
requests to the tool design unit. The processes were therefore
optimized at the part level and could vary based upon the preferences
and judgements of the individual manufacturing engineer
responsible for the part.
Strategic Plan for the Plant
As cited above, it was obvious that the implementation team
and the existing plant personnel had their work cut out for them.
Recognizing that manufacturing excellence is not a point on a map,
but a goal which is dynamic and driven by changes in technology
and market forces, we selected a combination of strategic initiatives.
Individually, each only contributed incrementally. However, in
whole they resulted in a quantum leap forward while allowing
flexibility for the unexpected.
While assured of management's continued commitment, we
were careful to schedule the implementation of initiatives such that
recognizable results would be attained as early as possible. This
also served to motivate everyone involved based on our theorem that
"success breeds success, and everyone wants to be with and support
a winner."
As stated earlier, the initiatives developed to produce disks,
hubs, drum rotors and spacers were based on group technology in
its broadest terms. The initiatives included changes to equipment,
factory layouts, processes and procedures, as well as a restructuring
of the organization. The group technology concept primarily derives
power from two sources: leverage and focus. Simply stated,
leverage is the ability to magnify the benefits that can be achieved by
the resources applied. Focus is the ability to concentrate on, and
limit deviation from, a specific goal. The concept's attributes of
leverage and focus, applied equally well to both physical and
organizational elements of the Southington plan.
The main aspect of what we termed physical changes,
consisted of the decision to incorporate the use of flowlines for disk,
hub and spacer manufacture and the use of cellular manufacturing
areas for the drum rotors. Organizationally, the business unit
concept was the main feature, with each business unit having
responsibility for specific families of part types, which are identified
as their charter parts. The physical and organizational changes made
are explained more fully as follows:
Physical Changes
It was understood at the outset that the objectives for the
Southington plant could not be realized without a major commitment
to upgrade manufacturing equipment. As a result, approximately
$173 million dollars were expended over a five year period for new
and refurbished machine tools and equipment. In general, these
machines represented the latest in machine technology. Some of
these machines were purchased to obtain the capacity and or
capability needed to manufacture new parts or features and not to
upgrade existing equipment. In addition to machine tools, another
$50 million had been spent to improve the facility and upgrade the
resources used in the various s,4pport functions. Typical examples
of these expenditures include a new waste treatment facility, an
automated storage and retrieval system, an air conditioning system
for the entire facility, new or refurbished machines for the tool
room, diagnostic equipment for machine repair, and computer
systems to improve operations such as tool design, parts
processing, scheduling, and planning.
The "generic" machines purchased and installed in
Southington included horizontal and vertical turning centers,
drilling/boring machines, broaches, grinders, shapers and milling
machines. Typically, these machines are operated via a DNC
system and CNC controls and include tool changers, tool and part
probing capability, and in some cases table or pallet changers.
Several "process specific" machines were also purchased, including
electron beam welders, inertia bonders, automatic clean lines,
automated nondestructive inspection systems and vacuum furnaces.
Picture, if you will, a plant with on-going delivery
requirements for a wide variety of products, in which you plan to
replace, rebuild or move almost 100 percent of the equipment. Add
to that picture, the logistics involved in having to "out-source" the
manufacture of most of the existing product (mainly to other Pratt
facilities) and "in-source" the new charter part product line. On top
of all this, add the need to simultaneously implement the
organizational changes required by the strategic plan. The approach
used in facing this challenge was to institute both the physical and
organizational changes in parallel, with physical changes
determining the schedule.
Flowlines and Cellular Areas
The focus on charter part responsibility and the heavy
investment in new equipment provided an opportunity to re-examine
and optimize the manufacturing schemes for relatively narrow
families of parts. As stated earlier, up until this time the shop was
organized in a classic job shop format with all turning in one
department, all milling in another, and so on. It was not uncommon
for a part to travel many miles from start to finish.
Employees who performed the various operations on parts
were generally in separate groups and may well have been at
opposite ends of the plant. Information concerning the effects of
one process on another was communicated through paperwork
systems or third parties (if at all). Obviously, this environment
offered limited opportunity for real process improvement. When the
decision was made to move toward cellular manufacturing, it was
decided to do so with an added twist. In cellular manufacturing, the
part or part family can move in a rather random or flexible motion
from one machine to another within the cell until completion. In
order to provide maximum control and visibility of the process and
maximize throughput, Pratt & Whitney decided to change the cell
into U-shaped flowlines in which the machines were arranged in the
same order as the manufacturing process. Thus, the parts would
enter a flowline, pass from machine to machine down the line, and
eventually exit as a finished part. Every effort was made to preserve
the "purity" of this concept -- the only exception being some of the
surface treat operations and nondestructive inspection systems
which had to be located away from the flowlines due to
environmental or safety considerations. Excluding these operations,
part flow is essentially a continuous path, and parts travel through
the process without retracing steps or leaving the flowline. In the
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4. flowlines, one-on-one discussions between employees who could
see the whole process and view the results of their contributions,
dramatically accelerated productivity and part quality improvements.
To enhance communications, conference rooms were provided
within each business unit. These rooms are available for use at any
time to discuss challenges or concerns of the employees or
supervision.
Twelve disk and hub flowlines and a spacer line were
installed in Southington, producing approximately 150 different part
numbers. Using group technology, these parts were divided into
part families based on geometry, material, and process
requirements. Each flowline was then designed to match the
specific requirements of the part family, and generic processes and
tooling were established accordingly. Computer simulations were
utilized to determine the number of each machine type and its
location within the line to balance the flow. This is similar to the
technique used to balance a belt-driven assembly line.
A flowline, when properly implemented, enjoys several
advantages over a typical job shop or a conventional cell. First, the
flowline is, in essence, a mini-factory with all the necessary
resources within its domain. Second, process deficiencies or errors
are typically caught and corrected immediately, since the operators
can now see the process from start to finish. Third, focus on a
single part family provides leveraged opportunities for process
improvement. Fourth, economies of scale, based on volume of the
entire part family along with commonality of tools and fixtures, are
realized since similar parts are processed in a similar manner.
The raw material forgings for disks, hubs and spacers are
very costly because of the unique alloys required for jet engines.
Based on this fact, and the realization that it is mandatory to control
the total process, i.e.; quality, cost and delivery, the flowlines were
designed based on the principle that it is better to have the machine
wait for the part rather than the part wait for the machine. This is a
classic example of a conflict between what had become accepted as a
basic truism and what is sometimes needed for today's
manufacturing requirements.
In the past, our manufacturing engineers, foremen,
accountants and others involved in manufacturing had learned that
"maximum utilization of equipment is goodness." We now realize
"optimization of total resources is goodness." This type of conflict
during implementation confirmed another basic principle: people
inertia is one of the most difficult problems to overcome.
Surprisingly, people historically considered the best contributors are
often the most difficult to change. Perhaps that is not so surprising
since self-confidence in one's convictions is usually an attribute of a
good contributor. Overcoming the belief that it is mandatory to
maximize machine utilization, was perhaps one of the major
challenges in selling the flowline concept. Also, when we
challenged another learned principle, by requiring that "process
simplification" must be based on the effect it has on all the parts in a
family, and not on any one specific part, we found we had to take
the time to prove it to our manufacturing engineers. This is a major
issue since the motivation of the people involved is a critical factor in
implementing change.
Cellular areas allow more flexibility in the event of radical
changes in product design or process technology than do flowlines.
On the other hand, changes within family limits can be made faster
and at lower cost in a flowline. Drum rotors are fabricated using
either inertia bonding or electron beam welding, and, therefore,
form two distinct families. Since both families were undergoing
rapid technological change in part design and manufacturing process
when the strategic plan was being implemented, the decision was
made not to use flowlines but instead establish a separate cellular
area and business unit for each drum rotor family.
Organizational Change
Concurrent with these physical changes, a new and
compatible organizational structure, the business unit, was
implemented. The business unit operates in a condominium-like
environment, sharing some resources while maintaining dedicated
resources where appropriate and cost effective. Each business unit
has responsibility for a specific family of part types, its charter
parts. The units are self-contained (mini) factories. The manager is
responsible for the entire manufacturing process, including quality,
cost, schedule and employee development. We believe the physical
and organizational approaches enhance each other, since both are
designed to increase effective communication and move decision-
making as close as possible to the actual production point: the
operation.
To ensure the success of the business units, the physical
size, number of direct labor employees, and similarity of processes
had to be balanced in the design so a team approach was practical.
Reporting to the unit manager on the operations side were six to
seven foremen spread over three shifts. Each unit was designed for
approximately 150 direct and 10 indirect hourly employees. Also
reporting to the Unit Manager is a group of dedicated manufacturing
engineers, programmers and material planners. These employees
are located with the unit manager and his operational people on the
factory floor adjacent to the flowlines, enabling them to work as
team members and focus on continuous process improvement. Two
business units, one for each of the drum rotor types, were formed.
The twelve disk and hub flowlines were separated into three
business units each consisting of four flowlines. The spacer
flowline and an area which produced parts not included in the
plant's charter parts (scheduled for later transfer to another source)
were combined to form the plant's sixth business unit.
The grouping of four U-shaped disk and hub flowlines into
a Business Unit not only satisfied the manpower and control criteria,
it provided a physical benefit. By having outgoing legs of adjoining
lines side by side within a unit, the establishment of commonly
shared areas such as deburring and quality audit became feasible.
(Note: I said "quality audit," not "inspection.") We have disbanded
the two final inspection areas in the plant. They have been replaced
by quality areas in each business unit as we shifted responsibility for
inspection to the machinist. This was accomplished using two
initiatives: operator certification and point of origin process control,
which will be covered later. Although the inspectors still
organizationally report to the quality department, they are now
permanently assigned to a particular unit, are included in all group
meetings and problem solving sessions, and are considered an
integral part of the unit team.
The quality organization also has been modified. Although
the quality assurance manager still has a solid line to the vice
president of quality assurance, he now has a dotted line
responsibility to the plant manager. He receives technical direction
from the quality assurance vice president, but administrative
guidance such as operating and manpower budgets are directed by
the plant manager. This initiative is indicative of the removal of the
old walls between functional organizations. Each organization
maintains sufficient authority to ensure the attainment of its required
objectives but works jointly to maximize their total contribution.
Functional managers in areas such as manufacturing
engineering, materials and support services continue to report to the
plant manager. They have dotted line responsibility for their
individuals assigned to the units, as well as a solid line
responsibility for a small "core group" operation. This provides
technical coordination and unique expertise for unit support.
Operators Certification
Machine operators at Pratt & Whitney inspect their own
work. In the past, however, the same dimensions or characteristics
were checked a second time by inspection, usually at a later stage of
the operation or when the part was finished. Form the viewpoint of
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5. the operators, this approach tended to diminish the importance of
their inspection, since they knew they could rely on the quality
inspectors to prevent "escapes." Under this approach, control of
quality tended to be viewed as the province of the quality
department. In order to dramatically change this misconception and
place responsibility for product quality more directly on the
shoulders of the individuals best able to control and influence it, a
joint manufacturing/quality program called "Operator Certification"
was implemented throughout the Plant. This program was designed
to control quality at the operation level and to reduce inspection of
the finished part from 100 percent to a statistically-based audit.
Machine operations are now given the training and tools
necessary to perform essentially all inspections. The operator is
then put through a formal qualification program and, once qualified,
is continuously monitored by the quality department in order to
sustain qualification. In addition, the fixtures, tools and gauges are
qualified and the process is monitored to continuously ensure
process capability. The operators enter their measurement data into
a computer system which is audited by the quality department based
on sampling plans to ensure compliance. Operators are subject to
decertification if they fail to perform to required standards. An
added benefit found with this approach is that operators will not
hesitate to speak up regarding concerns with the adequacy of tools,
gauging or instructions. This provides a strong incentive for rapid
corrective action.
A logical extension of the Operator Certification program is
now being implemented and is called Point of Origin Process
Control. As the transition has been made from manual machines to
numerical control and computer numerical control equipment, the
capability of the machine tool, fixtures and cutting tools play a larger
and larger role in governing the quality of the product. Point of
Origin Process Control uses statistical methods to isolate, identify
and control the many variables that impact the repeatability of the
process. This initiative also is compatible with our concept of
broadened group technology. Since we have separated the parts into
families and have used generic processes and tooling on specific
groups of machines, we have expanded the population and increased
the availability of samples. In other words, since we generate
specific characteristics in a family with the same process, tooling
and machines, we are not limited to a specific part number when
collecting data for analysis. It is also true that when we implement
corrective or improvement action, it applies to all of the parts in a
family -- not just one.
Family Of Parts Processes
As alluded to earlier, group technology was used extensively
to consolidate a large number of parts into a few part families. To
realize the potential benefits of similarity, family processing must be
implemented. Family processing is the use of generic or master
systems that group common or similar elements into a single
program. The master program is a permanent base that designs
processes consistently. It selects the machines, tooling and gauging
as well as provides detail instructions on how and in what sequence
they are to be applied. The system may or may not be
computerized, but must contain fixed logic. It is this logic that
modifies the output using variable data input to describe individual
parts which comprise the family. The output can be in the form of
planning sheets, numerical control tapes, drawings or any
combination thereof, required by the particular application. The
fixed logic ensures similar parts are processed in the same manner
using consistent tools and fixtures. The objective is to optimize an
entire family and improvements to one part are transferred to others.
The introduction time for new parts can be dramatically reduced as
well as the costs associated with tooling, gauging and the operator
learning curve.
The implementation of family of parts processes provides a
quantum step over the normal method of developing a unique
process for each part. This approach, however, requires the typical
manufacturing engineer to undergo a rather extensive cultural
change. With conventional parts processing, the manufacturing
engineer's natural inclination is to optimize the process for his
particular part irrespective of the parts in the family. The cultural
change required is not limited to manufacturing engineers.
schedulers, tool designers, foremen, operators, and every other
employee in the plant are directly affected. If they do not modify the
way they perform their function, the benefits will not be realized.
To overcome this hurdle and turn around what is often an ingrained
mindset, a stepped approach was taken for implementation for the
family of parts processing philosophy.
The first step was to install flowlines with the assignment of
parts by family. The second step was to modify the part process by
taking advantage of obvious similarities while reducing the number
of cutting tools utilized. Since most of the flowlines have more than
one family, the next step was to assign a manufacturing engineer
from each flowline with the responsibility to adjust the process so
that one common set of cutting tools could be used. By direction,
the number of tools could not exceed the tool storage capacity of the
machines used. Controlling the number of tools forced the use of
more generic processing and fostered collaboration with design
engineering.
These actions led to the standardization of some of the part
holding fixtures, all of which greatly reduced the time required to
change from one part to another. Perhaps a more important result is
that such actions physically demonstrate to the Manufacturing
Engineers and others the benefits the family process will provide
when applied. As new parts are added to a flowline, they are
immediately incorporated into a family of parts.
Rule-based Manufacturing and Design
The next phase is a natural evolution and involves the
computerized generation of the generic process instructions,
computer numeric control tapes, fixtures design, gauge design, and
forging design, for the families of parts. We call these steps "rule-
based manufacturing." When combined with computer-generated
product design, called "rule-based engineering," we will have
attained a truly total improvement -- the benefits of which are
obvious.
Rule-based manufacturing is not a dream of the future
awaiting a major technological breakthrough. It is the application of
common sense and today's technology. We have implemented
programs of each type mentioned above, with the exception of the
generation of generic process instructions. We are modifying our
computer-aided process planning software to add logic capability,
while using the existing system with manual interaction to produce
generic instructions to test logic elements prior to beginning full
development. I do not wish to mislead you into believing we are
near completion in this area. We have only scratched the surface of
rule-based manufacturing. We are, however, in the implementation
stages and learning daily.
Engineeringeering Integration
I will only touch briefly on this subject. It should be
intuitively evident that the application of our group technology
concept would be impossible, or at least seriously limited, without
the full cooperation of product design engineering. As with other
organizational barriers, we have instituted programs to knock down
the walls between manufacturing and design.
Pratt & Whitney has instituted a series of teams, called
charter part councils, comprised of experts from marketing, finance,
engineering, production, customer support, quality and even
suppliers. The charter part councils review engine segments such as
compressors, turbines, etc., using a group technology approach.
Integrated product teams, again comprised of people from various
functions, receive guidance from these councils as well as strategic
business sources, to evaluate new designs. A primary objective of
these and other similar teams is to shorten the lead time required to
design, develop and build new engines or incorporate product
improvements.
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6. Support Groups
As these initiatives were implemented, the role of the various
support groups increased in importance. Most impacted were the
machine service and tool room groups who maintain the machines,
fixtures and gauges used by both manufacturing and inspection.
Since process capability depends on continuous preventive
maintenance, these groups play an ever-increasing role in
manufacturing's success.
The financial group also takes on added responsibility.
Traditional accounting methods can lead to decision (or indecisions)
which can literally stifle all efforts for improvement. Fortunately,
outdated accounting and financial control systems are now being
changed to more fully recognized financial indicators that are more
consistent with long-term manufacturing profitability and
competitiveness.
RESULTS
Were our efforts rewarded? The answer is a resounding
YES! The items below identify some of the operating improvements
realized at the Southington plant since the implementation of
business units, flowlines and the other initiatives discussed herein.
Our work load has grown by nearly 45 percent, yet our
performance continues to improve. Business units 1, 2, 3 and 4
have essentially achieved 100 percent on-time delivery for several
years, and the plant is presently exceeding 90 percent delivery to
schedule requirements. Part lead times have been reduced by about
50 percent with an obvious favorable impact on the work-in-process
inventory levels.
Units 1 and 4 achieved the first division triple. A triple is
when a business unit achieves 100 percent on-time delivery, has less
than 2% scrap rework and repair, and attains the asset management
goals set for the unit.
The Plant's efficiency measurement for direct labor has
improved nearly 20 percent since 1987. This improvement has been
made despite ongoing plant rearrangements and new product
introductions. Not only has efficiency improved, we are only
cutting chips on parts that we need to meet our schedule. Gone are
the days of cutting chips just to improve a single measurement.
The rework and repair rate for all product lines was reduced
by more than 50 percent in just three years. This enables us to
spend our time more effectively, working to improve and refine the
manufacturing processes.
On a plant-wide basis, activity associated with quality
reviews has been cut more than 50 percent. As a result, inspection
activities have been reduced to audits on 80 percent of our
manufacturing operations. Dimensional and materials review board
activity has also dropped substantially as a result of these
improvements.
These numbers are interesting, but some of the really significant
improvements cannot be measured so easily. Here are some
examples of savings we have attained in using Rule Based
Manufacturing for tool design.
DESIGN TIME REQUIRED (then)
- CDL Fixture 40 hours
- Sutton Fixture 70 hours
- Broach Tooling 45 hours
- Total 155 hours
DESIGN TIME REQUIRED (now)
All Fixtures 0.5 hour
The hours of tool design saved have obvious cost value, but the fact
that we are building a foundation for implementing changes in days,
not weeks or months is much more important.
LESSONS LEARNED
The changes described above have been implemented over a
seven year period and a great deal of work remains. We are in a
very dynamic business and a number of modifications have been
made in response to changing market demands. One flowline has
been completely restructured and minor changes have occurred in
many of the others. Out of all the chaos of rearranging and
rebuilding an operating plant during this time period, five lessons
stand out above all the rest.
1. The importance of good planning cannot be overstated. It is
critical that the problem be properly defined and that a "complete"
solution be developed. In this sense, complete means that
interactions are understood and the segments of the plan allow
flexibility. The path may not be precisely defined, but the overall
objective must be known. In a multi-year project such as that at
Southington, a number of obstacles were encountered that could not
have been foreseen during the initial planning stages. Such
problems will occur. The important issue is that these problems
were resolved in a manner that supported the long range objectives.
2. The power of dedicated, hard working people cannot be
overestimated. The improvements realized at Southington are the
result of a plant-wide team who, through their tenacity, would not
allow themselves to be sidetracked by short term problems. These
people also serve as a major communications link with the other
operating units and support groups which, over time, promotes the
positive change necessary for continuous improvement.
3. Technology is only a tool and not a solution. Using the
"right" manufacturing technology can greatly improve the operations
of a business unit or plant. However, the implementation of
technology is usually far more difficult than its selection. A
mismatch between the technology selected and the environment to
which it is to be applied can lead to serious operating problems and a
long term competitive disadvantage.
4. Physical changes are not sufficient in themselves to turn
around or improve the manufacturing operations within a plant.
Physical changes must be accompanied by organizational changes to
ensure success. The latter changes are in fact far more difficult to
accomplish but are perhaps more critical in realizing improvements
in the overall operation.
5. You can not do everything at once. All of the initiatives
discussed have value and when properly applied may help virtually
any organization. However, successful implementation requires a
great deal of focus and the proper sequencing of elements.
Remember, success breeds success, it motivates people at all levels
of an organization. Getting one thing to work before moving on to
the next may appear to extend the total project time required,
however, a house built on quicksand may not have long-range
market value.
The relative importance of any of these five lessons will of course
vary with the nature of the project. In retrospect, we may have been
able to do it better, but I believe it is more important that we did it.
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7. CONCLUSION
Pratt & Whitney has undergone major changes in response to its
customers requirements. The manufacturing division has
significantly contributed to these changes by lowering cost,
improving responsiveness and upgrading quality. The Southington
plant implemented a strategic plan to support this initiative primarily
based on group technology. It, coupled with a compatible
organizational structure, business units, and approaches to problems
built on a few basic principles was focused on a single objective.
This action has enabled the plant to realize significant gains and
establish a solid base for continuous improvement. The
interdependence of quality, cost and delivery has been recognized
and the strategy is designed to optimize them in total. Though the
balance between these objectives may vary by business their
combined effect for any successful business must be customer
satisfaction.
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