mpd 575 design for x term i fall 2008 cohort 9 design for retool brian armstrong kim calloway 1ml1...
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MPD 575 Design for XTerm I Fall 2008
Cohort 9
Design for RetoolBrian Armstrong
Kim Calloway1ML1
December 1, 2008
22
Design for Retool
• Introduction to DFR
• Heuristics
• Key Principles of DFR
• Procedures for DFR
• Examples
• Conclusion
• References
3
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
4
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
5
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
6
DFR Heuristics
• 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
7
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.
8
DFR PrinciplesSome 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 to the development of incremental product improvement
9
DFR PrinciplesComponent:
•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 concern.
10
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).
11
Connecting Rod Sample Process Flow
12
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
13
DFR Procedures (cont)•CAD / TCe is invaluable for component interface and sub-system 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 underbody press and Lincoln Knock Down (KD) fixtures.
14
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 versus CNC; Robot transfer versus shuttle feed.
15
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
16
Sample 543 Chart for Engine Assembly
17
Sample 543 Chart for Engine Assembly
18
TCe Global Search
19
CAD of Coyote Engine in Shipping Rack
10.9mm CLEARANCE - OIL FILTER TO SHIPPING RACK
2C3E-6A642-BB OIL COOLER
P415
AA5E-6714-AA
20
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.
21
Make Like Production
ME
Suppliers
PDPrototype& PPM
Plant
Retool creates less disruption to the MLP process because Plant and ME are almost fixed The Plant
selection is typically mandated to PD and ME requirements mostly fixed
22
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
23
Examples
• Connecting Rod
• Engine Oil Cooler
• Specialty Vehicle Team (SVT)
24
Connecting RodThe Right Way
25
Connecting RodThe 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
26
Connecting RodThe 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)
27
Connecting RodThe 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
28
Connecting RodThe 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.
29
Engine Oil CoolerThe 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”
30
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
31
P415 Engine Oil Cooler
P415 INLINE OIL COOLER STUDY
OIL COOLER INTERFERES WITH ALTERNATOR
OIL COOLER INTERFERES WITH DRIP SHIELD
16.26mm OIL COOLER CLEARANCE TO FRAME RAIL
11.5MM CLEARANCE COOLER TO BELT (NOT INCLUDING SLAP)
33
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
34
Go See!
Oopsie. Found another problem. The engine cannot be picked level with the poorly designed eye hooks. This makes the cooler package condition worse!
We are measuring 15mm clearance to the stanchion. CAD said we had 17mm… Your friends will lie to you.
35
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.
36
CONCEPT PACKAGE MODEL –80mm WIDTH, 39mm HEIGHT, 340mm LENGTH
CLEAN OIL IN TO COOLER - 15 dia
COOLED OIL TO BLOCK – 15 dia
WATER IN TO COOLER FROM WATERJACKETS 10 dia
WATER FROM COOLER TO BLOCK – 15 dia
38
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
39
SVT
2000 SVT Cobra R
40
SVT (cont)•SVT programs are often times built with same carry-over 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.
41
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).
42
FRONT VIEW- (Con Rod #4)0.015mm CLR TO PISTON SQUIRTER TUBE
43
Con Rod #4 to Cyl Blk3.45mm clr
44
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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