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Models Aren’t Meant to Be Rigid!. A Case New Holland Combine Case Study. Epicenter Development Group Client List. Automotive/Trucking Amtex Corporation – Ohio Bellemar Parts – Ohio Case New Holland – Nebraska Chrysler Motors/Jeep – Ohio Eaton Corporation - Kentucky, Michigan
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Models Aren’t Meant to Be Rigid! A Case New Holland Combine Case Study
Epicenter Development Group Client List Automotive/Trucking • Amtex Corporation – Ohio • Bellemar Parts – Ohio • Case New Holland – Nebraska • Chrysler Motors/Jeep – Ohio • Eaton Corporation - Kentucky, Michigan • Essex Specialty Products – Michigan • G.M. - Packard Electric (Ohio), Hydra-matic (Michigan) • Manchester Plastics - Michigan, Ontario • Monroe Auto – Michigan • PACCAR Truck Assembly Plant – Washington • Schlegel, Inc – Iowa • Ternes Packaging – Michigan • Toth Industries – Ohio • United Technologies Automotive - OH, MI, IN, IA, IL, TN • Volvo/GM Heavy Truck -Ohio Food/Pharm • Biery Cheese – Ohio • Ernst and Young (Boston Chicken) – Illinois • Frozen Specialties – Ohio • Great Lakes Brewing Company – Ohio • Hickory Farms – Ohio • Mallinckrodt Inc. – Missouri • Miller Brewing – Ohio • Ross Laboratories - Ohio, Michigan, Arizona Chemical/Plastics • GOJO Industries – Ohio • Johnson Wax Professional – Wisconsin • Master Chemical – Ohio • Mueller Plastics - Michigan, Ohio • Occidental Chemical – Ohio • Phillips Plastics – Wisconsin • PPG Industries • Spartan Chemical – Ohio • Struktol Company of America – Ohio • Sunbeam Plastics – Indiana • The Sherwin Williams Company - Ohio Construction • Owens-Corning - WI, Ohio, TN • Ryland Homes - Michigan Electronics • Proto-Circuits – Ohio • Thompson Consumer Electronics – Ohio • Tosoh, SMD – Ohio • Union Carbide – Ohio • Westinghouse Electric - Ohio Steel/Casting • American Spring Wire – Ohio • Doehler Jarvis - Tennessee, Ohio • North America Wire Products – Ohio • Pre-Finish Metals – Ohio • Rouge Steel - Michigan Other • Aeroquip/Trinova – Ohio • American Red Cross - Ohio • American Way Manufacturing – Ohio • Applied Material Sciences – Massachusetts • Checker Distribution – Ohio • Commercial Aluminum Cookware – Ohio • Davidson Plyforms - Michigan • Ecodyne – Ohio • FFr, Inc. – Ohio • Godfrey & Wing – Ohio • Goody Products - Georgia, Florida • Greenville Utilities – North Carolina • Harley-Davidson – Pennsylvania • I.D. Images – Ohio • Junior Achievement - Ohio • Kalb, O’Keefe and Sullivan – Ohio • Lott Industries – Ohio • Meyer Products – Ohio • OfficeMax Corporation – Ohio • Quickdraft – Ohio • Sonopress, Inc. – North Carolina • The Lincoln Electric Company • Weiss Industries, Inc. – Ohio • Weldon Pump • Whirlpool Corporation – Ohio
Simulation is Part of a Group Process at Epicenter • Simulation • Process Maps • Value-Stream Mapping • Etc. The GreenRoom Engineering Process
The BIG Takeaways! • Model flexibility is important. • You can build flexibility through: • Spreadsheets • Toggles • Rules-of-Thumbs • Subroutines • KISS Principle
Why is Flexibility Important? • Every once in a while a model needs to be built without all of the information… • People occasionally change their minds… • Regrettably the first design isn’t always the best…
Considerations for a Flexible Model • Put as many of the calculations and variables in a spreadsheet as possible (spreadsheets are “user-friendly” to people) • Create “toggles” in the model to turn on and off elements “on the fly” • Use Rules-of-Thumb that govern how information is used • Use subroutines so changes can be made more globally when necessary. • Keep things simple! (K.I.S.S. Principle)
Our Story Begins… • CNH was planning to invest in expanding their current paint system for planned production increases and to address current design capacity bottlenecks . • They had to redesign and modify the system within a short period of time to accommodate a planned volume increase. This would be a significant investment in time and money. • It was critical that the paint system handle the required production volume – “do or die” time! • CNH decided to model the new system and use the model to validate the design before making any modifications. There were lots of expensive design modifications to consider.
System Definitions • Carrier - Orange Trolley Device Permanently fixed to the Power & Free Conveyor. • Bare Carrier - Carrier with no Load Bar attached. • Empty Carrier - Carrier with Load Bar attached but no parts hanging. • Load Bar - The device attached below to the “carrier” where parts are hung. Load Bars are separated from the carrier for processing through E-Coat. Parts Parts
The Power & Free Conveyor Design… • Every position on the Power & Free Conveyor was modeled as a unique location • When one carrier moves to the next location, it can start a “waterfall” of carrier movements downstream. • Delays for carrier movements were calculated based upon user-defined formulas. This was tricky!
The E-Coat Dip Tank Design… • This was a series of tanks where parts were transferred by a number of automated cranes • We wanted to be able to easily modify the crane/tank assignments and sequence and timing of crane movements.
Flex Design Principle #1 Put as many of the calculations and variables in a linked spreadsheet as possible. Spreadsheets are “user-friendly” to people. Before we built our model, we identified several variables that had the potential to change. We put these variables into spreadsheet tables.
Spreadsheet – P&F System Variables Every Variable that could be put into the spreadsheet – was!
Spreadsheet - Segment Travel Times • Each segment of the Power & Free conveyor was given a model name, index number and length in feet. • The spreadsheet calculated the travel time based upon the chain speed of the segment.
Spreadsheet - Crane Routes A spreadsheet system was developed to create crane routings for the model.
Spreadsheet - Crane Timing The spreadsheet also identified the crane movement and processing times for the model.
Flex Design Principle #2 Create “toggles” in the model to turn on and off elements “on the fly” In our model, we could manually turn off paint booths during the model run by manually setting certain key variables. This allowed us to rapidly experiment with how the system reacted to downtime or less available stations. Example: “wait until stop_paint2=0 #for manual shutdown of paint line”
Flex Design Principle #3 Use “rules-of-thumb” that govern how information is used Instead of hard-coding the model to handle every scenario, we used “rules-of-thumb” logic. This allowed the model to adjust to most scenarios (ex: rules to handle “traffic control” for carriers in the system)
Flex Design Principle #3 #part is e-coat only and zone is free and Stop19 queue is open If zlock[3,1]=0 and color=0 and size<3 and partcounter[(loc(l_Stop_19_Q_1))]+partcounter[(loc(l_Stop_19))]<2 then Begin zlock[3,1]=1 Nextroute=1 Route 1 Goto L2 End #part is e-coat only and zone is free and Stop19 queue is not open - send through topcoat If zlock[3,1]=0 and color=0 and size<3 and partcounter[loc((l_Stop_20_Q_1))]+partcounter[loc((l_Stop_20))]<2 then Begin zlock[3,1]=1 Nextroute=3 #send through topcoat Route 1 Goto L2 End #part is e-coat only and zone is free and Stop19 queue is not open and paint is backed up - send to paint overflow queue If zlock[3,1]=0 and color=0 and size<3 and partcounter[(loc(l_Stop_07_Q_1))]+partcounter[(loc(l_Stop_07))]<2 and size<3 and (paintoverflow_counter<paintoverflow_target or offshift>0) then Begin zlock[3,1]=1 Nextroute=4 #to paint queue Route 1 Goto L2 End
Flex Design Principle #4 Use subroutines so changes can be made more globally when necessary. Subroutines give you single point control over general model functions.
Flex Design Principle #4 #####This is a multi-purpose subroutine for chain delays ##s_stop_delay(stopped, queue_index, chain_trans, stop_point) # "stopped" is whether the unit stopped due to non-queue backups. # "queue_index" is the index of the next conveyor to consider for queue delays # "chain_trans" is whether there is a chain transfer involved in the move. This will always happen # "stop_point" says that this is a stop point - if there is a queue delay then we need to do a full start ###########start with whether we need to chain delay or not L1: If queue_index=0 then goto L2 #skip conveyor release delay step If clock(min)-Zone_Delay[queue_index,1]<Std_queue_delay then #wait if turned on(queue_index>0) or part is in next zone Begin wait .03 #wait 2 seconds and check again If stop_point=1 then stopped=1 #if we had to wait, then there is a stop delay Goto L1 end ########## L2: If stopped=1 then wait rand(STD_Stop_Delay_Max) min #we must do a chain start If chain_trans=1 then wait rand(STD_Chain_Delay_Max) min #we must do a chain to chain wait
Flex Design Principle #5 Keep things simple! (K.I.S.S. Principle) Our goal is always to use the simplest logic necessary to “get the job done”. Although we have several model locations, most P&F locations used the same operation logic with minor variations. #Index 20, next index 21 s_stop_delay(0,21,0,0) #forced to stop, next index, chain trans?, stop point?
Project Results • The model was used by the material handling engineers to redesign and validate the new paint system. The model logic was used as the basis for the new PLC logic • The new paint system was installed on time to handle the planned volume increase (and works!) • The model avoided the cost of a $500,000 crane upgrade. • Case New Holland has a model that can be used to experiment on the paint system for future improvements.
The BIG Takeaways! • Model flexibility is important. • You can build flexibility through: • Spreadsheets • Toggles • Rules-of-Thumbs • Subroutines • KISS Principle • Document the model !!!!