Stephen Hassler, Jeffrey Troester University of Nebraska - Lincoln Department of Industrial & Management Systems Engineering Contributors Hotsy Equipment Co. (NE)  Roy Gage – Sales Representative  Dennis Klingemann – Sales Representative Lincoln Industries (NE)  Bill Hancock – Area Leader, Fabrication  Eric Jacobs – Development Engineer 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. 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. 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. 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. INTRODUCTION Company Profile, Project Field, Problems, & Objective 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. 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. STUDY DETAILS Analysis Method & Findings 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 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. Current Layout SAW DEBURR CARTS BEND WASH EMPTY AREA (90 FT 2 ) ≈ 100 FT 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 Photographs SAW LOADING SAW RAW MATERIAL DEBURR MACHINE CHIPS CARTS WASH BEND MACHINE UNLOADING BENDER 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. 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. Other Benefits Added Washing Capacity Liberated Wash Station Operator One Year Warranty on Washer Less Consumables (Gloves, Rags) Less Material Handling Equipment (Carts) Cleaner, More Orderly Facility 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 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 $7.85  Total per Wash = $7.85 $39.25  Total per Day = $7.85 * 5 = $ Months  Payback Period = 334 Workdays = 16 Months  Salvage Value Not Considered, Likely Substantial Wash Operation Time Study Results  Unit Times = 36 s (for 25) / 43 s (for 15)TOTAL 900 s (See Below) Move Cart to Wash Station20 s Idle- (Often > 100 s) Lift Cart with Crane and Dunk in Bath 120 s Cart Air Dry and Release from Crane 100 s Hand Wipe (25) Tubes640 s Idle- (Often > 100 s) Move Cart to Bend Operation20 s Key Observations  Excessive Idle Time  Frequently Congested Workstation  Operator Sets Operation Pace  Potentially the Bottleneck Operation Develop Alternatives Seek Expert Opinion – Idea List  Power Washing Cabinet  Power Washing Conveyor System  Laser Cutting (No Chips)  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 Verify Feasibility of Alternatives ALTERNATIVE FEASIBILITY DETERMINATION Power Washing CabinetFeasible Power Washing Conveyor SystemInfeasible – Poor Cleaning Laser CuttingInfeasible – Cost Water Jet CuttingInfeasible – Cost Precision SawInfeasible – Cost Vacuum (Handheld or Fixed)Infeasible – Poor Cleaning Magnets (Handheld or Fixed)Infeasible – Poor Cleaning Water Bath with Drying FansInfeasible – Poor Cleaning 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? PROPOSAL DETAILS Description & Benefits Description Power Wash Cabinet Suggested Settings  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. SAW DEBURR CARTS BEND WASH ≈ 10 FT Proposal – Install Hotsy Model 7663 Purchase Cost  $10, 650 Tube Fixtures (5)  $1,250 Consumables  $1,200 / Year TOTAL – YEAR 1  $13,100 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. VACUUM EXPERIMENT “More Value with Less Work” – Philosophy of Lean Manufacturing Image Sources: