Optimizing High-Mix Low-Volume Operations

Shahrukh A. IraniDepartment of Integrated Systems Engineering

The Ohio State UniversityColumbus, OH 43210

PHONE: (614) 688-4685EMAIL: irani.4@osu.edu

WEBSITE: http://ise.osu.edu/biosketch_SIrani.cfm

Agenda Types of Manufacturing Systems

What type of manufacturing system do you manage?

What makes jobshops (high-mix, low-volume, MTO) different from any “Toyota-type” plant?

Limitations of the (Toyota)Lean tools

Examples of high-mix low-volume (HMLV) manufacturing systems

CASE STUDY: Optimization of the layout of an entire plant

CASE STUDY: Optimization of the setup on a press

A Toolbox for High-Mix Low-Volume Manufacturers

Spectrum of Manufacturing SystemsQ

UA

NT

ITY

(Vol

um

e)

MIX(Variety)

High

Low

Low High

Assembly Lines or Transfer Lines

Flexible Flowshops

Manual Cells

Flexible Mfg.Cells

Jobshops

$ALES ($)

MIX

(R

)

QUANTITY (Q,T)

Ou

tlie

rsIn

a P

art

Fam

ily

LOW

HIGHPROTOTYPES

STRANGERS

RUNNERS

REPEATERS

P

What is Your Manufacturing System?

• Jobshops Assembly Facilities– High mix of products i.e. many different routings– Part families may not be known– Product mix segmentation must be done– Setup times, cycle times, lot sizes, etc. vary significantly– Wide variety of product designs and equipment types– Typical facility has a Process Layout (= batch-and-queue)

• Different (and Difficult) Business Environment– Demand is unstable– Lot sizes change– Customer loyalty and sanity are non-existent– Production schedules are driven by due dates (not Takt Time)– Shifting capacity constraints – Due dates are different and subject to frequent changes

Lean for Toyota Lean for Jobshops

Strategic Planning Top-Down Leadership Motivated Workforce 5S Total Productive Maintenance Setup Reduction Error-Proofing Quality at Source Visual Workplace Right-sized Equipment Standardization of Work

X Right-sized (= Inflexible) Machines

X Kaizen Events (Mainly by Operators)

X 20th (not 21st) Century Managers

X Pencil-and-Paper Problem Solving

X Value Stream Mapping

X One-Piece Flow Cells

X Product-specific Kanbans

X FIFO Sequencing of Orders

X Pacemaker Scheduling

X Inventory Supermarkets

X Scheduling using Takt Time

X Heijunka/Load Leveling

X Assembly Line Balancing

Many Lean Tools are NOT Universal

How to Recognize a High-Mix Low-Volume Manufacturing System?

Forge Shop (≈500 Routings)

MTO Industrial Scale Fabrication Facility

763IRONW

STORAGE LOCATIONSX Y Z

Shipping811ASM

770WHLBR

771HCFIN/771TEXTR

771VIKIN

763FSROB 764/763 WELDM

761POLSH

761SPWLD

761ASY

761DBURR

761TWELD

761HSTUD/761PEM

761FORM

761PUNCH

771FSWHL

LASER761AMADA

770MODBO

812ASM

770PANG764BURNM

764SHR20

763BDSAW

763ACRO

763SHR16 763PRBRK

763DRLPR

764PSMA

X

Z

Y

764CDROB

764SUBMR764UNPUN

764BRAKE

764BEVLR

763MONRC 763

MON45

771SNDBL

Flexible Machining Cell

7

6

5

1

4

23

9 8

10

12

11

7

6

5

1

4

23

9 8

10

12

11

Finish Grinding Department

Factory Layout Optimization at Ulven Forging

Current State

Future State

Actions Taken

An additional processing area was created in the Drop Hammer building where cleaning,finishing,packaging and shipping were consolidated.

The 158 ton Trim Press was replaced by a 440 ton press that was positioned next to the 5000# Hammer. This eliminated the transportation of large forgings to a distant 350 ton Trim press. Also, a 350 kW induction heater and conveyor were purchased and co-located with this press to form an Upset Forging cell.

A new 2.5” Upsetter was purchased and positioned next to the 3000# Hammer to form an Upset Forging cell.

Actions Taken (contd.)The 1.5” Upsetter was replaced with a faster machine and

positioned next to the 700 ton Press to form an Upset Forging cell.

A crane was installed over the 5000# Hammer to reduce piston change-out time, reduce die key tightening time and to facilitate product movement in the area.

A portable Marvel Hacksaw and 1.5” Bar Shear were acquired.

A CNC Mill was acquired and positioned next to the EDM machine to reduce vendor costs and lead times for die sinking.

BenefitsApproximately 5% cost savings on annual sales of $ 6 million

WIP reductions were significant

Lead times quoted to customers were reduced

Throughput ($ales) increased

Since this company is a defense supplier, they were reluctant to release financial and delivery performance data that could be seen by their customers (Defense Logistics Agency and Department Of Defense)

Press Setup Optimization at Hirschvogel

Observe and Document the Press Setup

Work Locations around the Press

Sequence of Tasks in Press Setup

Operator Motion Traffic around the Press

16

1

79

17

8

15

14

6

22

12

10

11

5

New Workstation Layout for the Press

Operator Motion in Previous Layout

Operator Motion in New Layout

Press Setup Time: Before vs. After

ActivitiesCurrent Process Redesigned Process Difference

No. Time % No. Time % No. TimeOperations 247 1:32:07 71% 235 1:28:53 79% -12 -0:03:14Inspections 32 0:11:28 9% 31 0:11:23 10% -1 -0:00:05Transport. 135 0:17:54 14% 92 0:12:45 11% -43 -0:05:09

Storage 0 0:00:00 0% 0 0:00:00 0% 0 0:00:00Delays 12 0:09:01 7% 0 0:00:00 0% -12 -0:09:01Total 426 2:10:30 100% 358 1:53:01 100% -68 -0:17:29

57:07

00:00

02:52

05:45

08:38

11:31

14:24

17:16

20:09Initial Time Taken Revised Time Taken

Tim

e (i

n m

in.)

0 5 10 15 20 25 30 35 40 45 500

2,500

5,000

7,500

10,000

12,500

15,000

17,500

20,000

22,500

Number of Setups

Num

ber

of P

arts

Pro

duce

d

Potential Increase in Production = [EPT – (# of Setups * Time/Setup)] / Cycle Time per Part

Estimation of Increased Production

0 5 10 15 20 25 30 35 40 45 50 $-

$50,000.00

$100,000.00

$150,000.00

$200,000.00

$250,000.00

$300,000.00

$350,000.00

Lowest Revenue per Part

Average Revenue per Part

Highest Revenue per Part

Number of Setups

Rev

enue

s fr

om E

xtra

Pro

duct

ion

Potential Increase in Revenue = [EPT – (# of Setups * Time/Setup) / Cycle Time per Part] * $/Part

Estimation of Increased $ales

Part # Demand Price/ Part RevenueA1234 6,000 $ 15.55 $ 93,300.00 B3456 3,300 $ 7.00 $ 23,100.00 D6755 7,500 $ 12.50 $ 93,750.00

Extra Parts 16800 Extra Revenue $ 210,150.00

Category Initial Proposed % DecreaseSetup Time (min) 130.5 60.86 53.3%

Number of Activity Steps 426 358 16.0%

Distance travelled by Operator (steps) 1167 797 31.70%

Potential Increase in Revenue

Savings in Setup Time

Benefits

Parallel Task Scheduling for Press Setup

1 Operator 113.02 min (Current State) 2 Operators 60.86 min (Parallel

Execution of Activities) 3 Operators 60.86 min (Unnecessary, 2

operators are OK)

Gantt Chart for Optimized 2-Person Setup ProcessOp #1

Op #2

Optimization could Enhance Every Lean Tool

Value Stream Mapping

Work Order Release

Multi-Period Slotting of

Orders

Demand Forecasting

Cell Design

Scheduling Material Handlers

Scheduling Supplier

DeliveriesWIP

Inventory Control

Work Center Scheduling

Warehouse Design

Current Project at Pompano Beach

CURRENT STATE“4H” LEADERSHIP

• Walks the Gemba• Knowledgeable• Beyond TLSS• Competitive• Respects Employees• Efficient Fire Fighters (Risk Managers)• Change Managers• Invested in Talent and Technology

ENGAGED WORKFORCE

• Lean Thinkers• “Factory of One” Problem Solvers• Empowered• Multi-skilled• Team-oriented• IT Savvy• Collaborative

INDUSTRIAL ENGINEERING

• Work Measurements• Facility Layout• Ergonomics• Scheduling• Variety Control• Value Analysis/Value Engineering• DFMA• Flexible Mfg. Cells• Product/Process Standardization• Product Mix Rationalization• etc.

LEARNING ENTERPRISE

• Cafeteria Chats• E-newsletter• Wikis• Kaizens• Online Chat Groups• Idea Boards• Annual Conference• Resource Center - E-books - Case Studies - Videos - Online Apps - etc.

COMPETING THROUGH

INNOVATION

• Value Network Mapping• M3 Facilities• Flexible Focus (GT)• Product Mix Segmentation• ERP+FCS+MES• IT-enabled JIT Communications• Virtual Cells and Distributed Teams• Water Striders• Real-time Order Tracking• PLM+CAPP• Agile Suppliers

UNIVERSITY PARTNERSHIPS

• Co-Curricular Projects• Co-ops• Internships• Faculty R&D • Executives on Loan• Factories as “Test Beds”

FUTURE STATE

MORE….

A Toolbox for HMLV Manufacturers

Acknowledgements

The PRO-FAST Program is enabled by the dedicated team of professionals representing the Defense Logistics Agency, Department of Defense and industry. These team mates are determined to ensure the Nation’s forging industry is positioned for the challenges of the 21st Century. Key team members include: R&D Enterprise Team (DLA J339), Logistics Research and Development Branch (DLA – DSCP), and the Forging Industry Association (FIA).

Acknowledgements

Project Champion: Craig KaminskiProject Engineer: Haydn Garrett

Project Champion: Andrew UlvenProject Engineer: Jim Huiras

Project Champion: Joe KracheckProject Engineer: John Lucas

Project Champion: John WilburProject Engineers: Thomas Slauta

WWWEBER METALS, INC.ALUMINUM AND TITANIUM FORGINGS

Project Champion: Thomas StysProject Engineer: Jorge Alvarez

Project Champion: Kevin ShawProject Engineer: Greg Muniak

Project Champion: Dick JohnstonProject Engineer: Todd Sheppard

PFAST Development TeamDr. Rajiv RamnathDr. Rajiv Shivpuri

Dan Gearing

Jon TirpakRussell BeardVicky McKenzie

Questions?