Multidisciplinary Engineering Senior DesignProject PO6208 – ArcWorks Closure Tube Assembly

Adaptation Preliminary Design Review02/24/2006

Project Sponsor:ARC Works of Monroe County

Team Members:Team Leader George Gooch, Bill Lucas, Chris Donati, Drew Stone-

Briggs, Hui Kim, Mike Hayden, Mike Levis, Jeff Coppola

Team Mentor:

Dr. DeBartolo (ME) and Dr. Marshall (IE)

Acknowledgements:This material is based upon work supported by the National Science Foundation under

Award No. BES-0527358.Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science

Foundation.

Presentation Overview Sponsor

Who they are What is their current process

Team Goals How are we going to help ArcWorks Needs, Feasibility, and Concepts

Final Concept What improvements are being made Time, Flow, Material Handling

SD II

ArcWorks

ArcWorks is the vocational division of the Arc of Monroe County

Have been serving individuals with developmental disabilities and their families for over forty years.

Specialize in providing subcontracting manufacturing services

Comprised of over 250 assembly operators

ArcWorks – Closure Tube Assembly (CTA) A process that supports the assembly of a

bent stem closure with a tube attachment

Quantities produced are close to 500,000 units per year

Currently there are 3 process steps The team is dealing primarily with steps 2 and 3

CTA - Components

Finished Closure

Components

Closure (Various Sizes) Adapter Tube

(Various Lengths)

Step 1 – Straw Cutting Process Machine

10 tubes at once are inserted into the top of the automated tube cutter. The machine cycles, cuts the tubes and they drop through into a box.

CTA - Step 2 (Closure/Adaptor Sub-Assembly) Process MachinesClosures are placed in the bottom fixture and Adapters are placed in the top fixture of one of two style manual presses. The presses are cycled to create the Closure / Adapter Sub-assembly.

CTA - Step 3 (Final Assembly Press) Process Machine

Closure / Adapter Sub-Assemblies are placed in the top fixture of the automated press. Tubes are placed in the bottom fixture. The machine is cycled to create the final assembly.

Team’s Task

Lean Development – integration of sub assembly production orders/releases to ensure minimum/maximum quantities are on hand and flow as required (SD I)

Production Process – improvement of the assembly process, changeover & set-up, ergonomics/safety, and improvement of operator productivity (SD I)

Purchasing Function – ordering of the raw tubing that is cut to length for finished goods assembly (SD II)

Inventory Management – of both raw and cut tubing (SD II)

Needs Assessment

Tools Used

Problem Scope/Definition The mission of this design project team, PO6208, is to redesign a

process that supports the assembly of a bent stem closure with tube attachment called the Closure Tube Assembly. In this design the team hopes to improve the process flow, daily production and worker safety/comfort.

Objective Trees

5 Why’s

Needs Assessment - Outcome

It was decided through evaluations that this machined needed to: Combine assembly steps Decrease the number of moving parts Limit complexity of design Create fixtures that can be used for all product

sizes Use standard components Improve ergonomics Add counters

Feasibility Assessment

Tools Used

REST Resource, Economics, Schedule, Technical

Pugh Method Un-weighted, all attributes equally important

Weighted Comparison Method Looks at attribute importance

REST Method

Compares the chance of success of each idea Rating Scale

1=low chance 5=high chance

Design Idea Avg. Score 1 - 4.10 2 - 4.13 3 - 3.36 4 - 4.10 5 - 3.90 6 - 3.83

Top 3 = Idea 2, 1, 4

Pugh Method

Idea 1 Idea 2 Idea 3 Idea 4 Idea 5 Idea 6

+ 7.00 7.33 6.00 8.50 5.83 4.67

- 2.60 2.60 7.50 1.33 3.17 5.00

0 12.50 12.17 8.17 11.83 12.67 12.00

Compares against a baseline considering all attributes are equally important

Top 3 – Idea 4, 1, 2

Weighted Method

1 2 3 4 5 6

3.854 3.663 2.786 3.779 2.953 3.115

Compares against a baseline considering all attributes are not equally important, but have a weighting Idea

Top 3 – Idea 1, 4, 2

Feasibility Assessment - Outcome Main concerns after feasibility assessment:

Fixtures Closure Holding and Size Variation Tube Holding and Size Variation Adapter Holding

Assembly Alignment Combining Operations Budgeting

Feasibility Assessment - Results Top 3 ideas from feasibility methods

Idea 1 Idea 2 Idea 4

These ideas were the basis for the teams final design.

Final Concept

Step 1 – Part Placement

Step 2 – Press Anti-Tie Down Buttons

Step 3 – Adapter Press

Step 3 – Close Up of Adapter Press

Step 4 – Cylinder Returns

Step 5 – Manual Sub-Assembly Move

Step 6 – Manual Straw Placement

Step 7 – Gripper Press

Step 8 – Dual Cylinder Press

Step 9 – Gripper Return

Step 10 – Dual Cylinder Return

Step 11 – Assembly Removal

Performance Needs

Pneumatic Design Objectives

Improve safety OSHA 1910.217(b)(6)(i)

Limit cost Limit the stroke length of the press cylinders Actuate the press cylinders simultaneously or

independently Control speed and force

Pneumatic Layout

Analysis of Design ( Mechanical ) Design Parameters

FEA Calculations

Assembly Step Force (lbs) Comments

Closure - Adapter 8.75 Max5.40 Average

24mm red closure and clear adapter create max force

Tube - Adapter 3.00 Max2.11 Average

PPCO tube and red adapter create max force

Engineering AnalysisResultant Displacement

Air Cylinder Bracket Support Max Displacement

5.86 x 10-4 inches Location: End of Bracket

Deformation Scale = 3464 Conclusion:

Bracket Support is Rigid

Engineering AnalysisVon Mises Stress Contour Plot

Air Cylinder Bracket Support Max Stress

780 PSI Location: Bracket Connection

Factor Of Safety= 65 Conclusion:

Withstands Applied Forces

Engineering AnalysisFatigue Analysis

Air Cylinder Bracket Support Fa=Fm= 10 lbs Fatigue Strength=Endurance Limit Factor Of Safety w/

Mod Goodman Criterion= 35 Conclusion:

Withstands Infinite Cycles

Fa, Fm

Engineering AnalysisBuckling Analysis

Tube Holder Section 1

Euler Method: Pcr= 11 lbs Factor Of Safety= 2

Section 2 JB Johnson Method: Pcr= 3446 lbs Factor Of Safety= 626

Conclusion: Neither Section will Buckle Possible Improvement:

Limit exposed tube length in Section 1Pcr

2

1

BOM

Improvements - Time

Time Comparison Current Process New Design Process

Step Description Time Step Description Time (sec) (sec) Insert Closure 2 Insert Closure 2 Insert Adapter 2 Insert Adapter 2 Press 2 Press 2 Remove CA 2 Move CA 1.5 Insert Tube 2 Insert Tube 2 Insert Closure 2 Insert CA 2 Insert Adapter 2 Press 4 Press 3 Remove CTA 2 Remove CTA 2 Total Time 18 Total Time 12.5

•Estimated productivity increase of 88 CTA’s per hour

Improvements – Material Handling

Retrieve TubesFrom Hallway(Time – 60)

Cut Tubes(Time – 2)

Place Cut TubesIn Box

(Time – 10)

Move Tube from

Cutter to Pallet(Time - 12)

Move Tube from Pallet to

Final Assembly(Time - 10)

Retrieve Closure

And Adapters From Hallway

(Time - 45)

Transfer Parts from Boxes to

Bins(Time – 12)

Assemble ClosureWith Adapter

(Time – 8)

Place CA In Box

(Time – 2)

Move CAto Pallet

(Time - 12)

Move CA from Pallet to Final

Assembly(Time - 10)

Fill Bins with TubesAnd Closure Assembly

From Box(Time - 20)

Assemble into Final Assembly

(Time – 8)

CurrentManufacturing

Process(All times in seconds)

Box Final Assembly(Time - 5)

27 ft

1 ft

13 ft

8 ft

1 ft

1 ft

1 ft

1 ft

8 ft

12 ft

1 ft

1 ft

10 ft

Transfer Parts from Boxes to

Bins(Time - 12)

1 ft

Tube CuttingOperation 1

Closure Sub-AssemblyOperation 2

Final AssemblyOperation 3

Final Times and DistanceTube Cutting

Time - 106 secDistance - 51 ft.

Closure Sub-AssemblyTime - 99 secDistance - 33 ft.

Final AssemblyTime - 33 secDistance - 2 ft.

Retrieve TubesFrom Hallway

(Time - 60)

Cut Tubes(Time – 2)

Place Cut TubesIn Box

(Time -10)

Move Tube from

Cutter to Pallet(Time - 12)

Move Tube from Pallet to

Final Assembly(Time - 10 )

Retrieve Closure

And Adapters From Hallway

(Time - 45)

Fill Bins with Tubes,Closures, and

Adaptors From Box(Time - 20)

Assemble into Final Assembly

(Time – 8)

FutureManufacturing

Process(All times in seconds)

Box Final Assembly(Time - 5)

27 ft

1 ft

13 ft

8 ft

1 ft

1 ft

1 ft

10 ft

Transfer Parts from Boxes to

Bins(Time - 12)

1 ft

Tube Cutting Process

Operation 1Final

Assembly Operation

2 + 3(Combined)

Final Times and DistanceTube Cutting

Time - 106 secDistance - 51 ft.

Final AssemblyTime - 78 secDistance - 12 ft.

Improvements – New Machine Multiple operations done by one operator

Machine mounted to table for stability

Combines two process steps Eliminates material handling between stations Reduces process time

Improvements – Ergonomic/Safety Ergonomically friendly

Eliminates repeated manual motion Reduces ranges of motion Common plane of motion

Safety Anti-tie-down buttons E-stop

SD II - plans

Investigate Warehouse/Inventory Issues Re-order Points Safety Stock Flow of Material

Desired Outcomes – Manufacturing Area Increased productivity by the ArcWorks team Fewer rejects Higher satisfaction of workers Layout Redesign

Economic Order Quantity -EOQ

Defines the optimal quantity to order that minimizes total variable costs required to order and hold inventory. Q * = optimal order quantity C = cost per order event (not per unit) R = monthly demand of the product P = purchase cost per unit F = holding cost factor; the factor of the purchase cost that is

used as the holding cost (this is usually set at 10-15%, though circumstances can require any setting from 0 to 1)

H = holding cost per unit per month (H = PF)

Questions?

Backup Slides

Following Slides

Straw Cutting Improvements Manual Tube Feeding Concept

Needs Worksheets

Following Slides

Objective Tree – Inventory Management

Inventory Management

Purchasing Warehousing Final Product

Reorder Points Warehousing

Quantity Reorderd

Frequency of Reorder

Order High Volumes

Order Low Volumes

Order Frequently Order Infrequenty

LocationSize of

Inventory

Product LocationWarehouse

locationLow Inventory

QuantityHigh Inventory

Quantity

Quantity Quality

Inspection

BadGood

Objective Tree – Production Process

Production Process

Material Handling Assembly Quality Inspection

Frequency of Handling

Less Manual Process

Determine good products

Determine bad products

High handling frequency

Low Handling Frequency

Failsafes ConsistencyErgonomically

Correct

Take responsibility off of workers

Leads to better Quality

Better worker enviornment

Objective Tree – Fixture Development

Fixture Development

Aid in AssemblyImprove

ErgonomicsIncrease Product

Quality

Produce more parts at one time

Less Manual Machine

Combine multiple processes into one

Lower range of motion

More parts at once to reduce repetition

More like parts with less variance

Go-nogo checkReduce Cycle Time

Easier to use than current process

Quicker Machine Changeover

Less Scrap Parts

5 Why’s

A) Inventory Management

Why do you want us to improve your purchasing and inventory management system? Don’t want to run out of parts.

Why don’t you want to run out of parts? There is a 4 week lead time to

receive the parts from the vendor.

Why is there a 4 week lead time? That’s what the vendor gives us.

Why do you use that vendor? That’s the supplier we have

always used

Why have you always used that supplier? That’s who Nalgene used before

us and we never looked at any other options.

B) Fixture Evaluation

Why do you need new fixturing for your machines? The old ones are not efficient

enough.

Why aren’t they efficient enough for you? The current process is too

manual.

Why is the current process so manual? That’s the way the original

machines were designed.

Why were they designed like that? It met the needs at that time.

Why did it meet the needs then and not now? The demand from the customer

for Closure Tube Assemblies has increased. (This has created a bottleneck in the assembly department.)

Feasibility Worksheets

Following Slides

Weighted Method – How the weightings were achieved

Weighted Method – How the weightings were used

Top 3 Ideas

Following Slides

Original Concepts

Idea 1

Idea 2

Original Concepts

Original Concepts

Idea 4

Concepts from Peer Review

Following Slides

Assembly Process Improvement

Pin Style Automated Press Discussion: Pin tube support

Sliding Adapter Fixture Press Discussion: Closure Interference,

Fixture Alignment, Adapter Orientation

Assembly Process Improvement Two Stage CTA Press

Discussion: CTA Removal, Rotation

CTA Process w/ Magazine Feeder Discussion: Alignment

Feeding Concepts Automated Feeding

Discussion: Cost, Complexity, Durability, Clip Manufacturability

Also… Closure?

Feed Escapement

Tube Adapter

Gantt Chart – SD I

Gantt Chart – SD II