Transcript No Slide Title

MPD 575 Design for X
Term I Fall 2008
Cohort 9
Design for Retool
Brian Armstrong
Kim Calloway
1ML1
December 1, 2008
Design for Retool
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Introduction to DFR
Heuristics
Key Principles of DFR
Procedures for DFR
Examples
Conclusion
References
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Introduction to DFR
What is Design for Retool?
• To reequip with tools ~ Webster
• To revise and reorganize, especially for the
purpose of updating or improving~ The Free
Dictionary
• Utilize existing capital facilities / equipment to
produce (manufacture / assemble) new and
improved products ~ Kim and Brian
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Introduction to DFR (cont)
Why Design for Retool?
• Easier to make running changes / incremental improvements
• Facilitates Make Like Production (MLP) prototype requirements
as process is well defined
• It’s often the only option if late changes are required or if late
decisions drive component changes which in turn affect process
• Saves money; return on capital investment, less M.E. resource
investment
• Reduces engineering risk as process failure modes are well
understood
• Shorten development time; faster time to market
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Introduction to DFR (cont)
What are the drawbacks of Design for Retool?
• Can limit design flexibility on all new designs for numerous
reasons
• Undesirable component characteristics are sometimes carried
forward because they are too costly in terms of process change
to correct
• Can impact engineers to become technically lazy with the
mindset that components / processes are carry-over; Can
promote complacency
• Business risk that competition is using newer / better process
methods obtaining edge in performance, quality and cost
• Old equipment and all the associated concerns with its use
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DFR Heuristics
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If it’s not broke then don’t fix it
Minimize the # of machining / assembly planes
Minimize the # of transfers and orientations
The more knowledgeable the component engineer is
with the current process the better the potential for
incremental product improvements given the
constraints of the current process
• Engineers should know the process the way you
know your own house. You have to live in the
process to understand what is good, what is bad and
what should be changed.
• Knowledge saves time, effort and money
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DFR Heuristics (Cont)
• Sometimes the unforeseen or unthinkable happens;
Murphy’s Law applies.
• If your manager says it won’t happen, then it probably
will
• Late design changes are more difficult to deal with
than up front engineering assumption related
changes
• Any change requires giving something else up
(Heuristic from the game of Chess)
• CAD is your friend, but your friends will let you down.
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DFR Principles
Some basics that CPMT (Component) Engineers need to
know:
What are the processes used?
What is the process order?
What are the transfer systems?
How are components located and oriented?
What tools are used?
• CPMT Engineers do not need to know as much as the
M.E. Engineers, but a good understanding of the process
basics (answers to the questions above) will be invaluable
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to the development of incremental product improvement
Component:
DFR Principles
•Carry forward he best design features
•Try to eliminate excessive or negative features
•Minimize machining stock
•Simplify handling and assembly features
•Open tolerances where possible
Process:
•Eliminate unneeded processes
•Minimize repositioning and multiple fixture where possible
•Utilize capability data from existing process to ‘keep’ what
works well and improve processes where capability is a 9
concern.
DFR Principles
•Need to live in the “real world”
•Every Engineer would love to optimize their component for
maximum performance / functionality. There are obviously
many constraints preventing this one of which is utilization
of existing or common process (Retooling).
•Need to challenge status quo mind-set of M.E. within the
constraints of existing tooling
•Try to find offsets where concessions are granted to M.E.
and others.
•
Note: sometimes the offsets are to be found on a
sub-system or system level. Balance of ‘real estate’, cost,
weight or consumption (oil pressure budget, rotating or
reciprocating weights).
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Connecting Rod Sample Process Flow
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DFR Procedures
• Use TCe with CAD modeling for process systems
where possible
• Virtual fly thru and complete system modeling
is rare (nice in a perfect world)
• Models are typically available for transfer
pallets and shipping racks
• Generally an envelope around the pallet is
defined and physical protrusion past the
envelope creates problems
• 3D CAD modeling data generally isn’t available for
older machining lines so it’s important that the
engineers are intimate with the process
• GPDS VP prototype builds are required to have MLP
components
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DFR Procedures (cont)
•CAD / TCe is invaluable for component interface and subsystem to system interface
• Example: checking the position of an engine
component relative to a vehicle package
• CAD however doesn’t always have the most accurate
models of existing processes. This is due to the following:
• Modifications made to tooling after Job 1
• Inaccurate models due to “field fit” process installation
• Wear or damage
• Old equipment without such data (Lincoln underbody13
press and Lincoln Knock Down (KD) fixtures.
DFR Procedures (cont)
What should CPMT / Systems Engineers do in the absence
of CAD process data? How can improvements be made to
the components utilizing the existing process / assembly
equipment?
•Walk the line and spend some time there; supplier visits
when appropriate (APQP and SBLT are tools)
•Make notes of the process sequence and transfer systems
•Take pictures when appropriate
•Review capability data on critical processes
•Understand the limitations of the equipment ~ fixed spindle
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versus CNC; Robot transfer versus shuttle feed.
DFR Procedures (cont)
How can improvements be made to the components
utilizing the existing process / assembly equipment?
•Know your component!!
•Every feature should be understood!
•What are the features required by M.E.? Manufacturing
and assembly.
•Don’t just cut the ham in half as many excessive features
are unnecessarily carried forward.
•Benchmark competition often.
•Use lessons learned from other programs and solicit
technical experts when needed
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Sample 543 Chart for Engine Assembly
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Sample 543 Chart for Engine Assembly
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TCe Global Search
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CAD of Coyote Engine in Shipping Rack
P415
10.9mm CLEARANCE - OIL FILTER TO
SHIPPING RACK
AA5E-6714-AA
2C3E-6A642-BB OIL COOLER
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DFR Procedures (cont)
Make Like Production
Once improvements are made to a component the new
design must be verified. There are many prototype phases
in GPDS, including VP and post VP where components
must be MLP.
What is MLP?
When Prototype and Production has the same –
• Process Sequence
• Material Removal Rates (wet/dry)
• Same locating Datums
• Fixtures
• Tooling (durable/perishable)
• Inspection/Gauging methods and programs
• Assembly methods
using data to drive investment and resource decisions.
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Make Like Production
Retool creates less
disruption to the
MLP process
because Plant and
ME are almost fixed
ME
Prototype
& PPM
Plant
PD
Suppliers
The Plant
selection is
typically
mandated to
PD and ME
requirements
mostly fixed
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MLP (Engine Engineering)
• Early prototypes (pre-VP), rapid prototyping, early
concepts, and MLP can be supported in-house at Ford.
• Engine Manufacturing Development Operations (EMDO)
– EMDO uses process that simulate production process to produce
engine components
– Process Sequence
– Material Removal Rates (wet/dry)
– Same locating Datums
– Fixtures
• Beech Daly Technical Center (BDTC)
– Inspection/Gauging methods and programs
– Assembly methods
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Examples
• Connecting Rod
• Engine Oil Cooler
• Specialty Vehicle Team (SVT)
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Connecting Rod
The Right Way
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Connecting Rod
The Right Way
Increased engine speeds and increased
engine specific output (HP/L) drives
needed design changes to connecting
rod.
• Need increase strength while
simultaneously reducing rod weight
• Need to use the existing rod machining
line
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Connecting Rod
The Right Way
Rod Improvements:
• Material change from Powdered Metal to Forged Steel
– Allows use of less material for weight reduction and is stronger than
PM
• Maintain critical features for current process
– Rod shoulders for part transfer
– Clamping pads, pin-end radius for locating and rod cap gnorf
• Other functional improvements:
– Rolled threads to allow blind holes for weight reduction
• Lower stress concentrations
• Eliminate potential for chips in bolt hole
– Elimination of Piston Pin Bushing
• Reduces weight further
• Reduces part count and cost
– Tapered Pin End for weight reduction (Piston, Crank as well)
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Connecting Rod
The Right Way
The changes to the connecting rod necessitated
some changes to the process as follows:
• The harder material required changes to
boring, drilling, and grinding operations
• Speed and feeds had to be adjusted
• Fracture splitting of rod required laser notch
in lieu of the traditional machining broach
– The laser equipment was installed where the old
broach equipment was removed
– Some UAW push-back due to Health and Safety
concerns
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Connecting Rod
The Right Way
Summary:
All of the changes to the connecting rod were
containable via retooling the existing
manufacturing line. The improvements to the
connecting rod help the overall engine
system. The result is a lighter, stronger rod
that in turn allows for weight reduction of the
piston and crank shaft. Reducing the rotating
and reciprocating mass in the engine which
improves the overall engine efficiency.
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Engine Oil Cooler
The Wrong Way
Background:
In the spring of 2008 at FMC Engine
Engineering. Coyote V8 engine
program is in the M1D phase of
GPDS with S197 as lead customer
and P415 as the secondary but
higher volume customer.
– Preliminary testing indicates engine
oil temps are marginal
– Lubrication CPMT and Systems
Engineer are concerned and request
to package protect for an engine oil
cooler
– Coyote program manager denies the
request to package protect for the oil
cooler stating “this engine doesn’t
need an oil cooler”
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Engine Oil Cooler (Cont)
• Changes in other engine programs
results in the Coyote engine becoming
the lead trailer tow engine for P415.
– Oil temps that were marginal are now out
of specification
– Increased vehicle cooling is not feasible
– Engine oil cooler needs to be included in
the EAS Coyote package
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P415 Engine Oil Cooler
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P415 INLINE OIL COOLER STUDY
11.5MM CLEARANCE COOLER TO
BELT (NOT INCLUDING SLAP)
OIL COOLER INTERFERES
WITH ALTERNATOR
16.26mm OIL COOLER
CLEARANCE TO FRAME RAIL
OIL COOLER INTERFERES
WITH DRIP SHIELD
Engine Oil Cooler (Cont)
• The failure to package
protect for an oil cooler has
led to sub-standard design
clearances and required
process changes.
– Nut runners for oil pan to front
cover are mounted on fixed
slide driving a process
sequencing change
– Alternator install clearance is
sub-standard requiring an
operator assist as well as a
protective shield on cooler
during assembly
– Oil filter protrusion results in
specifying two different filters (a
stubby for assembly and
regular FL400 for service)
– EPSA cable rerouted
– Redesigned OFA to support
additional weight of cooler
Unique cooler shape results
in cooler tooling cost of ½
million USD
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Go See!
We are measuring
15mm clearance to the
stanchion. CAD said we
had 17mm… Your
friends will lie to you.
Oopsie. Found another
problem. The engine cannot
be picked level with the
poorly designed eye hooks.
This makes the cooler
package condition worse!
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Engine Oil Cooler (Cont)
Valley Mounted Cooler
If an engine oil cooler was part of the original
engineering assumptions, then more time and
resources would have been available to
design a product that utilizes the current
process without all of the sub-standard
clearances and process tear-ups.
A valley mounted cooler would package nicely,
but would require more time to sort through
the block casting and block retooling
changes.
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CONCEPT PACKAGE MODEL –80mm WIDTH, 39mm HEIGHT, 340mm LENGTH
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WATER IN TO COOLER FROM WATERJACKETS
10 dia
WATER FROM COOLER TO
BLOCK – 15 dia
COOLED OIL TO
BLOCK – 15 dia
CLEAN OIL IN TO
COOLER - 15 dia
Engine Oil Cooler (Cont)
Valley Mounted Cooler
• This package holds more promise than the external
OFA mounted cooler previously shown.
• Larger cooler capacity with better heat rejection
• Less coolant and oil pressure loss
• Package constraints limited to intake, knock sensors
and wire harness
• Fewer water / oil terminations reducing risk of leaks
• Requires more Retooling effort and higher cost for
the larger cooler
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SVT
2000 SVT Cobra R
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SVT (cont)
•SVT programs are often times built with same carryover process. This includes Powertrain and Final
Assembly
•SVT components are typically higher performance but
are confined to existing architecture / package’
•Iconic SVT products are additionally bound by
legendary ‘DNA’.
•Example: Mustang Boss 302 has always been
naturally aspirated, so if more power is needed,
forced induction is not an option.
•Catalog parts are sometimes used in these
applications. Performance is known, volumes are low to
warrant higher piece price without tooling investment. 40
SVT (cont)
The next two slides show a catalog racing connecting
rod (H-beam Manley). CAD modeling using Power Kit
to add motion to verify packaging and fit within the
cylinder block.
The shelf rod is fully machined. Verification for retooling
(or in this case, compatibility within the current process)
would be reduced to assembly processes only (piston
and rod sub-assembling, bearing install, piston stuffing
and bolt torque).
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FRONT VIEW- (Con Rod #4)
0.015mm CLR TO PISTON SQUIRTER TUBE
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n Rod #4 to Cyl Blk
5mm clr
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Conclusion
Engineers who are responsible for the design and
release of components should understand the whole
manufacturing process related to their component
and their system. A good analogy would be someone
familiar with the house that they live in. Everyone
knows what they like, what they don’t like and what
they would change if possible about the house that
they live in. Similarly, engineers should know the
manufacturing process to understand what is
currently possible, what is good about the current
process and what they would change if they could.
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