Team Dow Dan Greene, Fran Heil, Jacob Hersh, Prasant Muralidhar

Design Constraints

Problem Definition

Key Findings

•Operators need easy access to the blade for cleaning •Operators need to be able to see their hands and work while cleaning •Excess polymer should flow to a single point •The quality of the end product must remain the same

Cabinet

Cart

Blade Drip pan

Teflon/Delrin slider system

Final Concept Key Features •Blade slides all the way out on the Teflon/Delrin slider system for easy and safe cleaning •Cart allows the blade to slide all the way out with out bulky supports •Drip pan is angled for single point polymer containment •Cabinet keeps negative pressure throughout the system

Slider System

*Currently there is a collection basin that does not funnel to a collection point **For one year of normal use

Acknowledgments Advisor: Dr. James Glancey Sponsor: James Romesburg

Dow Engineers and Operators: Chuck Green, Dave Fogarty, Masayuki Kobayashi, Frank Tornetta Al Murrey, Allen

Weaver, Russ Kuchera, Dwight, Mike Matejik, Hank Clark

•The scraper section needs to be more accessible •The web dips into the polymer, goes over the large roller and the roller scraper removes excess polymer from the roller •The trough and scraper sections can separate

Concept Validation

Calculated velocity, u, to find flow rate Verified drip pan angle based on highest viscosity polymer≈2.42 Pa*s Angle of drip pan ≈1.5° > 1.2° (pipe draining standards)

1. Open channel flow calculation for drip pan

2. Full scale mock-up of support structure with Delrin and Teflon sliders

3. Pulling Force Test measured forced needed to over come static friction coefficient

•Replicated 1 year worth of pulls for slider system (about 1 pull per week) •Peak force during pull out (3σ) =19.8lbs

4. Accelerated Wear Rate Test weighed Teflon and Delrin strips to determine their life based on one year worth of use

Life = when the countersunk screws are exposed

•Delrin will last 531 years

5. Accelerated Drip Pan Flow Test measured the time it would take 5 gallons to flow out of the drip pan

To modify the Impreg Line for easier and safer maintenance of the Teflon roller scraper, while considering material containment and product consistency. The modification should be designed, prototyped, and tested.

Benefits to Dow: •Increased safety and ergonomics for operators •Decreased labor costs •Decreased downtime of the Impreg Line

Project Scope

•Forced needed to move blade from support structure meets the targeted value of 30lbs making the design ergonomically acceptable •Drip Pan test and the Open-Channel Flow analysis proved that a shifts (8 hours) worth of polymer will not overflow meaning less cleaning time •The sliding system will require minimal maintenance and cleaning

•Teflon will last 46 years Current Impreg Line state

Teflon Slide

Delrin Slide

Zoomed in view of the Teflon/Delrin slider system

y = 0.0429x + 12.225

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Flow Rate versus Drip Pan Slope

•Determined flow rate of liquid with μ = 2.42 Pa*s = 0.21 gal/min = 101 gal/shift

Rank Metrics Units Current Marginal Target

1 Meets Dow QC standards (Gap) inches 0 0 0

2 Ergonomics/Safety NIOSH Lift Equation (lbs per person) N/A <50 30

3 Weight pounds N/A <100 50

4 Time to clean blade/ drip pan minutes 20-30 <20 10

5 Flow rate out of drip pan Gal/shift (8 hrs) N/A <5 5

6 Times drip pan is cleaned Shifts (hours) 1 (8) 1 (8) 1 (8)

7 Access space (width) inches 15 >>15 36

8 Polymer collection points number 1* 1 1

9 Wear rate of sliders Mass loss (g)** N/A 0.3 0.1

inches (length) 95 95 95

inches (height) 5 5 5

inches (width) 0.75 0.75 0.75

11 Number of parts number 10 <15 10

12 Cost USD N/A <6000 4000

Size of blade apparatus10