Restoration of One-Piece Flow To Lincoln Industries

1. Stephen Hassler Jeffrey Troester University of Nebraska – Lincoln Department of Industrial & Management System Engineering Presented on April 15, 2009 Restoration of One-Piece Flow To Lincoln Industries

2. Contributors • Adventure Manufacturing, Inc. (OK) • Franek Laser & Fab Systems (MN) • Duane Franek – Owner • Hotsy Equipment Co. (NE) • Roy Gage – Sales Representative • Dennis Klingemann – Sales Representative • Lincoln Industries (NE) • Bill Hancock – Area Leader, Fabrication • Eric Jacobs – Development Engineer • North American Cutting Systems (CA) Images: www.adventureinmetals.com, www.franeklaser.com, www.hotsy.com

3. Company Profile, Project Field, Problems, & Objective Introduction

4. Company Profile • In 1952, Lincoln Industries was founded in Lincoln, NE as a small job shop for custom electroplating. • The company has grown to become Lincoln’s largest water user and North America’s largest metal finisher. • In its 500,000 square feet of production and warehouse space, approximately 500 people are employed. • Annual revenues have grown rapidly over the past decade and now exceed $100 million. Images: www.lincolnindustries.com

5. Project Field • Lincoln Industries (LI) is best known as North America’s largest metal finisher.  However, the company’s operations are diverse and our team took a look at their fabrication activities.  At a facility in Air Park (Lincoln, NE), LI fabricates exhaust stacks for semi-trailer trucks. Images: www.lincolnchrome.com

6. Original Problem • Unfortunately, after the production line was designed, installed, and operating, quality issues arose.  A set of operations occurring early in the production sequence was causing damage to the parts.

7. Original Remedy • A quick solution was developed by LI and another operation was added to the production process, though it occurred on a workstation off of the main production line.

8. Consequential Problem • By locating the workstation off of the main line, one-piece flow was disrupted.  As a result, material handling became excessive, processing time increased, and quality control declined.

9. Project Objective • It is the goal of the investigating team to develop a cost-effective proposal that remedies these undesirable byproducts and restores one-piece flow to the production line.

10. Analysis Method & Findings Study Details

11. Four Step Analysis Method • Understand Problem and Magnitude • Visual Aids, Quality Inspection, Time Studies • Develop Alternatives • Seek Expert Opinions, Creative Brainstorming • Verify Feasibility of Alternatives • Examine Attributes and Costs, Design Experiments • Evaluate Alternatives • Economic Analysis, Discuss Qualitative Factors

12. Understand Problem and Magnitude • Visual Aids • The team developed a simple facility layout diagram to convey the problematic nature of the current arrangement. • Photographs and video were taken to document the process and highlight production issues.

13. Current Layout SAW BEND DEBUR WASH EMPTY AREA (90 FT2) CARTS ≈ 100 FT

14. Lean Issues • Four of the Seven Wastes of the Toyota Production System (TPS) were glaringly obvious as a result of the current layout. • Waste of Transportation • Waste of Waiting • Waste of Inventory • Waste of Motion

15. Photographs RAW MATERIAL LOADING SAW DEBURR MACHINE SAW Images: www.lincolnchrome.com

16. Photographs CHIPS CHIPS CARTS CART

17. Photographs WASH WASH BEND MACHINE UNLOADING BENDER Images: www.lincolnchrome.com

18. Understand Problem and Magnitude • Quality Inspection • Though inefficient, the current wash operation sufficiently removes chips from the tubes. • Chips are being introduced from various sources such as material handling carts, gloves, rags, and tools.

19. Understand Problem and Magnitude • Time Studies • Surprisingly, the inefficient wash operation is not typically the bottleneck of the production line. • However, when the wash operation becomes congested, it definitely has the ability to function as the bottleneck.

20. Saw and Deburr Operation • Time Study Results • Mean/Median/Mode Unit Times = 49 s / 43 s / 44 s • Minimum/Maximum Unit Times = 34 s / 82 s • Key Observations • Excessive Work-in-Process (WIP) Buildup (25+ Tubes) • Operator Sets Operation Pace • Insignificant Operator Idle Time • Not Typically the Bottleneck Operation

21. Wash Operation • Time Study Results • Unit Times = 36 s (for 25) / 43 s (for 15)

22. Wash Operation • Key Observations • Excessive Idle Time • Frequently Congested Workstation • Operator Sets Operation Pace • Potentially the Bottleneck Operation

23. Bend Operation • Time Study Results • Mean/Median/Mode Unit Times = 88 s / 82 s / 68 s • Minimum/Maximum Unit Times = 66 s / 133 s • Key Observations • Machine Sets Operation Pace • Minimal Operator Idle Time • Potentially the Bottleneck Operation

24. Develop Alternatives • Seek Expert Opinions • The first technique for developing alternatives was to conduct interviews with LI management and assemble the ideas that had already been considered. • LI management had considered two types of solutions. Those that washed parts and those that did not generate chips in the first place. • Two wash systems included power washing cabinets and power washing conveyor systems. • To eliminate chips altogether, laser cutting, abrasive water jet cutting, and precision saws were considered.

25. Develop Alternatives • Creative Brainstorming • The second technique for developing alternatives was to do some “thinking outside of the box”. The team considered several unorthodox chip removal procedures. • The team considered only solutions that washed parts. • Use of vacuums and magnets were considered. Both in handheld and fixed configurations. Also, a simple water bath with drying fans was considered.

26. Develop Alternatives • Seek Expert Opinion – Idea List • Power Washing Cabinet • Power Washing Conveyor System • Laser Cutting (No Chips) • Abrasive Water Jet Cutting (No Chips) • Precision Saw (No Chips) • Creative Brainstorming – Idea List • Vacuum (Handheld or Fixed) • Magnets (Handheld or Fixed) • Water Bath with Drying Fans

27. Verify Feasibility of Alternatives • Examine Attributes and Costs • The team first considered whether or not each alternative would accomplish the intended purpose. • Cost data was then used to eliminate some alternatives. Due to current economic conditions (including recent layoffs at LI), most high cost alternatives were deemed infeasible. • Design Experiments • The team was forced to design experiments in some cases to verify alternative feasibility.

28. Power Washing Cabinet • Attributes • Sufficiently Cleans Parts (Prior Testing at LI) • Fits in Space between Saw and Bend Operation • No Labor to Dry Parts, Flash-Dry (60 s) • Smaller Batches • Drawbacks • Purchase Price = $10,650 • Still Batching Parts • Operating Costs, Consumables, Maintenance

29. Power Washing Conveyor System • Attributes • Fits in Space between Saw and Bend Operation • Transports Parts from Saw to Bend Operation • Pure One-Piece Flow • Drawbacks • Purchase Price = $20,000 to $30,000 • Unlikely to Effectively Clean Tube Interior • Operating Costs, Consumables, Maintenance • Labor to Dry Parts • Slip Hazards

30. Photographs POWER WASHING CABINET POWER WASHING CONVEYOR SYSTEM Images: www.adventureinmetals.com, www.globalspec.com

31. Laser Cutting • Attributes • No Metal Chips • Eliminates Need for Deburr Operation • Eliminates Need for Wash Operation • Precision Cuts • Cuts Harder Materials (Stainless Steel) • Drawbacks • Purchase Price = $300,000 to $400,000 • Operating Costs, Consumables, Maintenance • Hazardous Fumes

32. Abrasive Water Jet Cutting • Attributes • No Metal Chips • Eliminates Need for Deburr Operation • Eliminates Need for Wash Operation • Drawbacks • Purchase Price = $200,000 to $300,000 • Operating Costs, Consumables, Maintenance • Slower than Laser Cutting • Requires Abrasive Particles in Water to Cut • Abrasive Particles Necessitate Machine Cleaning

33. Photographs ABRASIVE WATER JET CUTTING LASER CUTTING Images: www.advancedwaterjet.com, www.alspi.com

34. Precision Saw • Attributes • No Metal Chips • Eliminates Need for Deburr Operation • Eliminates Need for Wash Operation • Cuts Harder Materials (Stainless Steel) • Drawbacks • Purchase Price = $400,000+ • Operating Costs, Consumables, Maintenance

35. Verify Feasibility of Alternatives • List of Experiments Designed • Vacuum (Handheld or Fixed) • Magnets (Handheld or Fixed) • Water Bath with Drying Fans

36. Photographs WATER BATH VACUUM MAGNETS

37. Verify Feasibility of Alternatives • Results of Experiments • Vacuum – Time Consuming, Only Fair Cleaning • Magnets – Time Consuming, Poor Cleaning • Water Bath and Drying Fans – Poor Cleaning, Slow Drying

38. Verify Feasibility of Alternatives

39. Evaluate Alternatives • Economic Analysis • Cost savings are likely to result from reduced labor (drying tubes), reduced overall processing time (from elimination of idle time), reduced WIP, potentially improved quality, and a cleaner, more orderly work space. • Will the savings from the installation of a power washing cabinet justify its expense?

40. Description & Benefits Proposal Details

41. Proposal • Purchase the Power Washing Cabinet • Install it in the Empty Space between the Saw and Bend Operation • Wash the Tubes in Batches of 5 • Wash the Tubes for 120 s • Let the Tubes Dry for 60 s • Spend Minimally on Consumable, Only Enough to Inhibit Washer Rusting

42. Photographs POWER WASHING CABINET HOTSY MODEL 7663 Images: www.hotsy.com

43. Current Layout SAW BEND DEBUR WASH EMPTY AREA (90 FT2) CARTS ≈ 100 FT

44. Proposed Layout SAW BEND DEBUR WASH WASH CARTS ≈ 10 FT

45. Rationale • Moving water seems to remove chips from the tubes better than other methods. For a relatively low cost, the team believes that LI can achieve significant savings with the installation of a power washing cabinet. However, the efficiency of the machine is dependent upon some batching. Therefore, pure one-piece flow will not be achieved.

46. Proposal Quote from Hotsy • Purchase Cost • $10, 650 • Tube Fixtures (5) • $1,250 • Consumables • $1,200 / Year • TOTAL – YEAR 1 • $13,100

47. Proposed Process • Power Washing Cabinet • Batch Size: 5 Tubes • Wash Phase: 120 s • Dry Phase: 60 s • Unload Phase: 50 s • Key Assumptions • Saw Operation Unit Time Increases (5 s) for Added Material Handling • Bend Operation Unit Time Increases (10 s) for Added Material Handling

48. Processing Time Comparison • Current Process • 25 Tubes 72 min + Wash Station Idle Time • 15 Tubes 45 min + Wash Station Idle Time • Proposed Process • 25 Tubes 74 min • 15 Tubes 45 min • Key Observations • Excessive Idle Time at Wash is Controlled • No Significant Changes to Ideal Processing Times

49. Labor Savings • Key Assumptions • Labor Expense (Hourly)= $15 • Source of Labor Savings • Labor Reduction at Wash Operation (1 Operator) • Idle Time Avoidance at Wash Operation (3 Operators) • Projected Labor Savings • Labor Reduction per Wash = 13 min = $3.35 • Idle Time per Wash = 6 min * 3 = 18 min = $4.50 • Total per Wash = $7.85 • Total per Day = $7.85 * 5 = $39.25 • Payback Period = 334 Workdays = 16 Months • Salvage Value Not Considered, Likely Substantial

50. Labor Savings Robustness • Calculated Savings are Intentionally Conservative • Using 6 Washes per Day or Idle Time Avoidance of 10 min Significantly Improves Expected Payback Period