Precision AirConveyPrecision AirConveyInternal Duct Cleaning SystemInternal Duct Cleaning System

December 10, 2007Sean DarrasNick RakovKatie SearLindsay Martz

Introduction to Introduction to PACPAC

PAC has designed a pneumatic linen-refuse system.

Mock SystemMock System

Project ScopeProject Scope

UD must develop a method to clean PAC’s Linen and Refuse Removal System

An inhibitor and deodorizer application must be developed

System System Specifications/ConstraintsSpecifications/Constraints

Duct Dimensions:◦ Outside Diameter: 20”◦ Thickness: Corners .135”,

Straightaway .105” Access panels are 40-100 ft

apart Pressure drop is 50 lbf/in2

Air flow is 55 ft/s ~ 60 mph Duct is made of (uncoated)

steel Plaque is caused by

liquid/debris in the system Most ‘Plaque’ builds up on

the turns Bag path can include a

double 90 degree turn System cleaned weekly

Design CriteriaDesign CriteriaWant Metric Target Value

Maximize Cleaning Performance

Plaque removal 80-100% removed

Durability # of uses or total miles traveled

3 to 5 runs without decreased performance

Minimize Time Time to clean one mile

1 hour

Maximize Range

Distance traveled at one time

1 mile

Minimal Labor Involvement

# of operators 2 in-house maintenance men

Inhibit and Deodorize

Quarterly Swab Test Dependent on Industry

Pre-existing SolutionsPre-existing Solutions

Customer Opinion:◦No Umbilicals ◦Requires Aggressive Cleaning◦Prefer Robot and Shuttle

ideas

Agitation Devices Robots

PIG

Concept IdeasConcept Ideas

Shuttle SpringSpinner Rocket

Spider

Rating Criteria:1: Should surpass target value0.5: Should easily reach target value0.2: Will probably reach target value0: Unknown

MetricImportance

(%) Rocket Spider Shuttle Spinner Spring

Plaque Removal 30 1 1 0.2 0.2 1

Durability 25 1 0.2 0.5 0.5 0.2

Distance Traveled 14 1 1 1 1 0.5

Time 14 1 1 1 1 0.5

Liquid Coverage 11 0 0 0 0.2 0

# of Operators 6 1 1 1 1 0.5

Final Score % 89 69 52.5 54.7 52

Chosen Concept: RocketChosen Concept: Rocket

Initial Concept Final Prototype

In the DuctIn the Duct

Clearance between shuttle and inside duct walls approx = 2 inches

Shuttle length greater than 20 in. to prevent yaw and pitch in the tube

Rocket- How it worksRocket- How it works

Propelled by system

Aluminum Frame

Rotated by system

Nylon Bristles

BrushesBrushesStiff Nylon Fibers

Channel is attached by brackets to main body

Channel Brushes

RotorRotor

Variable fin pitch

Variable number of fins

Liquid ApplicationLiquid ApplicationPrewash and Deodorizer

Sponge◦ Approximately 7 lbs (dry)◦ Dimensions:

Height 21” Diameter 19.8”

Fogger

Sponge

PrototypingPrototyping

Fabrication outsourced

to local Machine Shop

UD provided assembly instructions, detailed drawings, and fabrication support.

Objectives of TestingObjectives of Testing

Determine:◦Durability◦Time to clean one mile◦Distance that can be traveled at one

time◦Coverage of the prewash, inhibitor and

deodorizer◦Cleaning technique that maximizes

plaque removal

Maximum Cleaning Maximum Cleaning PerformancePerformance

Flat-Sheet Prewash TestFlat-Sheet Prewash Test

Surface # of swipes

Greased Lightening 6409 10ZEP 9Dry 20+Air Chalk 3

Sponge TestingSponge TestingBEFORE AFTER

Rotation TestingRotation Testing

Rotation TestingRotation Testing

36 degrees over 12 ft= ~1 Rotation per 120 ft

8 fins at 45 deg. gives maximum rotation

Final Verification TestingFinal Verification Testing

-Results agree with Flat-Sheet Prewash Test

90 Degree Rise

ConclusionsConclusions

•Rocket needs to Rotate One Rotation/Foot

•Current Rocket only rotates ~1 Rotation per 120 ft

•With no rotation, Rocket would need 54 levels of brushes

Recommended ProposalRecommended Proposal

Compromise:◦Double the amount of brushes

◦Requires1/2 rotation/foot◦Increase rotor diameter ◦Optimize fin design◦Clean more often

Total Cost to PACTotal Cost to PAC  Material Amount Price

Body

5052 Aluminum Sheet- 1/8" 10 sq ft

$2455 (Includes Labor)

5052 Aluminum Sheet- 1/16" 10 sq ft

Propeller

5052 Aluminum Sheet- 1/8" 1 sq ft

3/8" x 3/8" 12 ftBrushes 2 Sets of Brushes

$746.88100 Brackets

Fogger Flex-a-lite 2600 $300

Sponge 2 Sponges $120Filet Knife $30

Plaque Materials Soda, Eggs, Milk, Fake Snow, Air Chalk $25Participation Cost One time fee $5000

PAC’s Time Varies per employee $4,230*Total   $13,906.88

*Best estimate

Questions?Questions?

Supporting Material-RotorSupporting Material-Rotor