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Difference between revisions of "Kingston Hot Press: Process Improvements"

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(Heat Transfer)
Line 5: Line 5:
 
Currently, I am investigating the potential to design a plastic/paper composite extruder which would facilitate the production of feedstock for the Kingston Hot Press.
 
Currently, I am investigating the potential to design a plastic/paper composite extruder which would facilitate the production of feedstock for the Kingston Hot Press.
  
===Introduction===
+
=Introduction=
 
The organization ''Waste for Life'' (WFL) defines itself as "a loosely joined network of scientists, engineers, educators, architects, artists, designers, and cooperatives who work together to develop poverty-reducing solutions to specific ecological problems."<ref>http://wasteforlife.org/?page_id=2</ref> Through a collaboration with researchers and community members at Queen's University, the Centro Experimental de la Produccion (CEP) in Argentina, the Rhode Island School of Design (RISD), Smith College, and the University of Western Australia, the Kingston Hot Press has been designed and developed to provide the means of production to smaller cooperatives in communities in Argentina and Lesotho. The Hot Press allows the user to produce a value-added composite tile out of waste plastic and fiber (most commonly cardboard and paper). Currently three prototypes have been built, one at Queen's, one at RISD, and one at CEP. Detailed design drawings are available at the WFL [http://wasteforlife.org/wp-content/uploads/2010/02/Kingston-hotpress-documentation.pdf| website].
 
The organization ''Waste for Life'' (WFL) defines itself as "a loosely joined network of scientists, engineers, educators, architects, artists, designers, and cooperatives who work together to develop poverty-reducing solutions to specific ecological problems."<ref>http://wasteforlife.org/?page_id=2</ref> Through a collaboration with researchers and community members at Queen's University, the Centro Experimental de la Produccion (CEP) in Argentina, the Rhode Island School of Design (RISD), Smith College, and the University of Western Australia, the Kingston Hot Press has been designed and developed to provide the means of production to smaller cooperatives in communities in Argentina and Lesotho. The Hot Press allows the user to produce a value-added composite tile out of waste plastic and fiber (most commonly cardboard and paper). Currently three prototypes have been built, one at Queen's, one at RISD, and one at CEP. Detailed design drawings are available at the WFL [http://wasteforlife.org/wp-content/uploads/2010/02/Kingston-hotpress-documentation.pdf| website].
  
===Problem Definition and Scope===
+
=Problem Definition and Scope=
 
The WFL team has identified several key areas of design development that they would like to pursue <ref> http://wasteforlife.org/?page_id=425</ref>:
 
The WFL team has identified several key areas of design development that they would like to pursue <ref> http://wasteforlife.org/?page_id=425</ref>:
 
*Dimensions - The current Kingston Hot Press can produce a 24"x24"x1/4" sheet. A wider gap in the press could allow more width and perhaps allow for 3D molds. The size constraints could be circumvented if pieces could be produced in modules and then connected post-production.
 
*Dimensions - The current Kingston Hot Press can produce a 24"x24"x1/4" sheet. A wider gap in the press could allow more width and perhaps allow for 3D molds. The size constraints could be circumvented if pieces could be produced in modules and then connected post-production.
Line 19: Line 19:
 
Currently the temperature consistency problem has been resolved with very expensive aluminum plates. A heat transfer model could assist in the evaluation of different solutions and hopefully provide an optimal solution that could use less costly and more widely available materials.
 
Currently the temperature consistency problem has been resolved with very expensive aluminum plates. A heat transfer model could assist in the evaluation of different solutions and hopefully provide an optimal solution that could use less costly and more widely available materials.
  
===Client===
+
==Client==
 
There are several key stakeholders that I have identified for this project. Here at Queen's I am working to assist Dr. Matovic with design improvements based on the Hot Press prototype in Kingston. More broadly, I hope my work can contribute to the Waste For Life team. Finally the end-user of the hot press is the cartoneros, the workers who partake in the informal economy of waste in Argentina<ref>http://www.theargentimes.com/socialissues/urbanlife/cartoneros-recycling-the-city-/</ref><ref>http://secure.aidcvt.com/mcp/ProdDetails.asp?ID=9781608451630&PG=1&Type=RLMa&PCS=MCP</ref>.
 
There are several key stakeholders that I have identified for this project. Here at Queen's I am working to assist Dr. Matovic with design improvements based on the Hot Press prototype in Kingston. More broadly, I hope my work can contribute to the Waste For Life team. Finally the end-user of the hot press is the cartoneros, the workers who partake in the informal economy of waste in Argentina<ref>http://www.theargentimes.com/socialissues/urbanlife/cartoneros-recycling-the-city-/</ref><ref>http://secure.aidcvt.com/mcp/ProdDetails.asp?ID=9781608451630&PG=1&Type=RLMa&PCS=MCP</ref>.
  
===Goals===
+
==Goals==
 
I would like to develop a useful heat transfer model which could assist the WFL team in reducing the cost of the Hot Press. I would also like to take this opportunity to expand the reach of the WFL team and share their innovative design. Finally, I would like to provide a clear pictographic instruction manual for users of the Hot Press.
 
I would like to develop a useful heat transfer model which could assist the WFL team in reducing the cost of the Hot Press. I would also like to take this opportunity to expand the reach of the WFL team and share their innovative design. Finally, I would like to provide a clear pictographic instruction manual for users of the Hot Press.
  
===Constraints===
+
=Constraints=
 
The hot press should provide a low-cost tool to access the means of production and add value to "waste" products. As such, materials should be as economical and accessible to the carteneros communities as possible.
 
The hot press should provide a low-cost tool to access the means of production and add value to "waste" products. As such, materials should be as economical and accessible to the carteneros communities as possible.
  
 
Design work must be limited to theoretical analysis as significant empirical testing would require equipment not currently available for the budget and scope of the project. Future work could include an empirical evaluation of several plate designs using an array of thermal transducers (thermistors, or thermocouples) to determine realized temperature gradients in the hot press.
 
Design work must be limited to theoretical analysis as significant empirical testing would require equipment not currently available for the budget and scope of the project. Future work could include an empirical evaluation of several plate designs using an array of thermal transducers (thermistors, or thermocouples) to determine realized temperature gradients in the hot press.
  
===Prior Art===
+
=Prior Art=
 
At Queen's University Dr. Matovic has produced CAD drawings fully detailing the design and dimensions of the [http://wasteforlife.org/wp-content/uploads/2010/02/Kingston-hotpress-documentation.pdf Kingston Hot Press].
 
At Queen's University Dr. Matovic has produced CAD drawings fully detailing the design and dimensions of the [http://wasteforlife.org/wp-content/uploads/2010/02/Kingston-hotpress-documentation.pdf Kingston Hot Press].
  
Line 37: Line 37:
 
The original design used 1/4" steel plates to press and heat the tiles. To overcome temperature inconsistencies which were producing burnt profiles the prototype plates were replaced with 1/2" aluminum plates.
 
The original design used 1/4" steel plates to press and heat the tiles. To overcome temperature inconsistencies which were producing burnt profiles the prototype plates were replaced with 1/2" aluminum plates.
  
===Theory and Methodology===
+
=Theory and Methodology=
  
 
Although the design of a hot press plate must ideally involve both a heat transfer model and a finite element static stress analysis it will be assumed for the following optimization that based on previous work by the WFL team, the 1/4" steel plate provides a minimum benchmark thickness for the plate and a lower limit for allowable bending and deformation of the plate. Therefore the following analysis will focus on better understanding the heat transfer mechanisms in the heat press, and how these effect the performance of the press.
 
Although the design of a hot press plate must ideally involve both a heat transfer model and a finite element static stress analysis it will be assumed for the following optimization that based on previous work by the WFL team, the 1/4" steel plate provides a minimum benchmark thickness for the plate and a lower limit for allowable bending and deformation of the plate. Therefore the following analysis will focus on better understanding the heat transfer mechanisms in the heat press, and how these effect the performance of the press.
  
=[[Heat Transfer]]=
+
===[[Heat Transfer]]===
 
(see also the Wikipedia  [http://wasteforlife.org/wp-content/uploads/2010/02/Kingston-hotpress-documentation.pdf article])
 
(see also the Wikipedia  [http://wasteforlife.org/wp-content/uploads/2010/02/Kingston-hotpress-documentation.pdf article])
  
Line 50: Line 50:
 
Pictographic Instruction
 
Pictographic Instruction
  
===Final Design and Analysis===
+
=Final Design and Analysis=
  
===Cost Analysis===
+
=Cost Analysis=
  
===Conclusions and Recommendations===
+
=Conclusions and Recommendations=
  
===Future Work===
+
=Future Work=
  
===References===
+
=References=
 
<references/>
 
<references/>

Revision as of 22:39, 15 April 2010

MECH425 Project Page in Progress
This page is a project page in progress by students in Mech425. Please refrain from making edits unless you are a member of the project team, but feel free to make comments using the discussion tab. Check back for the finished version on May 1, 2010.


Check out the project on wasteforlife.org Hot Press Discussion Page

Currently, I am investigating the potential to design a plastic/paper composite extruder which would facilitate the production of feedstock for the Kingston Hot Press.

Introduction

The organization Waste for Life (WFL) defines itself as "a loosely joined network of scientists, engineers, educators, architects, artists, designers, and cooperatives who work together to develop poverty-reducing solutions to specific ecological problems."[1] Through a collaboration with researchers and community members at Queen's University, the Centro Experimental de la Produccion (CEP) in Argentina, the Rhode Island School of Design (RISD), Smith College, and the University of Western Australia, the Kingston Hot Press has been designed and developed to provide the means of production to smaller cooperatives in communities in Argentina and Lesotho. The Hot Press allows the user to produce a value-added composite tile out of waste plastic and fiber (most commonly cardboard and paper). Currently three prototypes have been built, one at Queen's, one at RISD, and one at CEP. Detailed design drawings are available at the WFL website.

Problem Definition and Scope

The WFL team has identified several key areas of design development that they would like to pursue [2]:

  • Dimensions - The current Kingston Hot Press can produce a 24"x24"x1/4" sheet. A wider gap in the press could allow more width and perhaps allow for 3D molds. The size constraints could be circumvented if pieces could be produced in modules and then connected post-production.
  • Heating Sources - Currently the plate heaters require electricity. CEP has expressed interest in a gas powered system.
  • Temperature Consistency - Initial tests had shown inconsistencies between the temperature distribution on the top and bottom plates. To remedy this, researchers at Queen's replaced the 1/4" steel heating plates with 1/2" aluminum plates.
  • Opening between top and bottom plates - Currently molds are slid between the heating plates. A "clam shell" lid design could allow for a more diverse range of geometries and facilitate the use of 3D molds.
  • Safety and Environmental Issues - Fire safety, emissions, pollutants.
  • Production Speed - The current system requires a time intensive production process to arrive at a single 1/4" composite tile. CEP has expressed interest in finding ways to improve throughput.

Currently the temperature consistency problem has been resolved with very expensive aluminum plates. A heat transfer model could assist in the evaluation of different solutions and hopefully provide an optimal solution that could use less costly and more widely available materials.

Client

There are several key stakeholders that I have identified for this project. Here at Queen's I am working to assist Dr. Matovic with design improvements based on the Hot Press prototype in Kingston. More broadly, I hope my work can contribute to the Waste For Life team. Finally the end-user of the hot press is the cartoneros, the workers who partake in the informal economy of waste in Argentina[3][4].

Goals

I would like to develop a useful heat transfer model which could assist the WFL team in reducing the cost of the Hot Press. I would also like to take this opportunity to expand the reach of the WFL team and share their innovative design. Finally, I would like to provide a clear pictographic instruction manual for users of the Hot Press.

Constraints

The hot press should provide a low-cost tool to access the means of production and add value to "waste" products. As such, materials should be as economical and accessible to the carteneros communities as possible.

Design work must be limited to theoretical analysis as significant empirical testing would require equipment not currently available for the budget and scope of the project. Future work could include an empirical evaluation of several plate designs using an array of thermal transducers (thermistors, or thermocouples) to determine realized temperature gradients in the hot press.

Prior Art

At Queen's University Dr. Matovic has produced CAD drawings fully detailing the design and dimensions of the Kingston Hot Press.

DrMatovicHotPressCAD.jpg

The original design used 1/4" steel plates to press and heat the tiles. To overcome temperature inconsistencies which were producing burnt profiles the prototype plates were replaced with 1/2" aluminum plates.

Theory and Methodology

Although the design of a hot press plate must ideally involve both a heat transfer model and a finite element static stress analysis it will be assumed for the following optimization that based on previous work by the WFL team, the 1/4" steel plate provides a minimum benchmark thickness for the plate and a lower limit for allowable bending and deformation of the plate. Therefore the following analysis will focus on better understanding the heat transfer mechanisms in the heat press, and how these effect the performance of the press.

Heat Transfer

(see also the Wikipedia article)

The Kingston Hot Press presents a particularly challenging heat transfer system to model. Six 750W Omega OT-2107 strip heaters are clamped to the two "press" plates which transfer heat and pressure to the mold and tile composite material. A cork rubber gasket provides insulation between the press plates and the steel weldments which provide the necessary structural support for the device. A simple on/off controller regulates the temperature of the center of the plate with a thermocouple transducer. Standard setpoints range between 150°C and 250°C. Since a tile (or film) can be pressed within 5-35 minutes depending on the thickness of the mold, the problem almost certainly falls within the transient time period. However, the plates are preheated to the setpoint temperature, and so a steady state model can assist in determining the ideal performance of the heating plates upon the initiation of the press cycle.

Plate Optimization

Pictographic Instruction

Final Design and Analysis

Cost Analysis

Conclusions and Recommendations

Future Work

References

  1. http://wasteforlife.org/?page_id=2
  2. http://wasteforlife.org/?page_id=425
  3. http://www.theargentimes.com/socialissues/urbanlife/cartoneros-recycling-the-city-/
  4. http://secure.aidcvt.com/mcp/ProdDetails.asp?ID=9781608451630&PG=1&Type=RLMa&PCS=MCP