Dimensions.07 Conference Meeting the Challenges of Thermal Packaging Designing a Cold Chain Package Doesn t Have to Take an Ice Age Mark Escobedo Chief Technologist Westpak, Inc
Outline Look at the Environment Three Prong Approach Package Design
Types of Thermal Packaging Active Requires refrigeration system Heat Pump Passive Frozen (Dry Ice) Refrigerated (2-8ºC)
The Challenge Narrow Temperature Range Thermal Characteristics of Product Insulated Material Properties Dynamic Distribution Environment
Measure the environment What temperature range do I design for? Measure the Environment What can we predict How Long? Overnight Air worst case 72 hours? Distribution Center
35 30 25 20 15 10 5 0-5 Average Temperatures in the Average Temperatures in the United States Portland, Or Billings, Mo Casper, Wy Columbia, SC Columbus, Ga Columbus, Oh Death Valley, Ca Denver, Co Des Moines, Id Detroit, Mi Honolulu, Hi Houston, Tt Huntsville, Al International Falls, Mn Juneau, Ak Las Vegas, Nv Los Angeles, Ca Memphis, Tn Miami, Fl Minneapolis - St. Paul, Mn Nashville, Tn New Orleans, La New York, NY Oklahoma City, Ok Omaha, Ne Orlando, Fl Philadelphia, Pa Phoenix, Az Salt Lake City, Ut San Francisco, Ca Avg High Temp ( C) Avg Low Temp ( C) Major U.S. Cities Temperature ( C)
80 60 40 20 0-20 -40-60 Record Temperatures in the Record Temperatures in the United States Billings, Mo Phoenix, Az Casper, Wy Columbia, SC Columbus, Ga Columbus, Oh Death Valley, Ca Denver, Co Des Moines, Id Detroit, Mi Honolulu, Hi Houston, Tt Huntsville, Al International Falls, Mn Juneau, Ak Las Vegas, Nv Los Angeles, Ca Memphis, Tn Miami, Fl Minneapolis - St. Paul, Mn Nashville, Tn New Orleans, La New York, NY Oklahoma City, Ok Omaha, Ne Orlando, Fl Philadelphia, Pa Portland, Or Salt Lake City, Ut San Francisco, Ca Record High Temp ( C) Record Low Temp ( C) Major U.S. Cities Temperature ( C)
Measure the Environment If we measure the environment We can develop our own protocol Statistical significance Time intensive Expensive What about other studies Literature Search Data published by Standards Organizations
Atmospheric Conditions: Example Temperature Study
Unmodified ISTA 5B Profile 60 Small Shipper 14 gel packs = 17.781kg (39.2 lb.) 50 Temperature C 40 30 20 10 0 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 Time (Hours) Small Shipper Vial Small Shipper Core Chamber 2 C 8 C
Unmodified ISTA 5B Profile 60 Large Shipper 22 Gel Packs = 27.942kg (61.6 lb.) 50 Temperature C 40 30 20 10 0 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 Time (Hours) Large Shipper Vial Large Shipper Core Chamber 2 C 8 C
Standards Organization ISTA 24 and 48 hour Summer Profile Domestic Small Package Express Freight Transport (Air) 50 45 40 Temperature ºC 35 30 25 20 15 10 5 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (Hours)
Theoretical Summer Profile Max A 96 Hour Summer Profile 35 30 25 20 15 6.3 C @ 96 hours 10 5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 0 Max A Max A Max A Max A Chamber Max A Max A Max A Core
Formula for Package Design Heat Transfer Thermal Mass Phase Change
Water and Phase Change Solid (Ice) Heat of Fusion 334 kj/kg Liquid (Water) Heat of Vaporization 2257 kj/kg
Why is Phase Change Important?
Phase Change Materials Advantages Energy Absorption Change between solid and liquid Water based materials 0C Disadvantages Can be expensive and sometimes toxic Many packages can meet requirements without these materials Difficult direct contact with product
Gel Packs Phase Change Refrigerant -1ºC (+30ºF) Gel Pack 0ºC (+32ºF)
Insulation Performance dependent on: Material properties Conductivity Surface properties (for radiation) Thickness Quality of Construction
Insulated Container Types Expanded Polystyrene Rigid Polyurethane Panels Lined Rigid Polyurethane
Package Design Made Simple A lot of insulation Lots of Thermal Mass Phase Change Material
Package Design Made Simple Consequences of poor design A very small payload A very large package That is difficult to move
Package Design Considerations Damage Criteria Acceptable Temperature Range Materials Refrigerant Type Thermal Mass of product Distribution Cycle Testing
Package Design Considerations Coolant Placement Adjacent to Product Restrain movement Select largest size possible Create a conditioned core
Evaluating the Package Thermal Performance Evaluation Sensitivity of sensors Locations of sensors Duration of collection What about Package Performance What does my package look like after distribution cycle?
Evaluate this Package Rigid Polyurethane container Flexible Polyurethane Foam Cushion top
Evaluate this Package Both are open cell materials Container is sealed with a solid poly material Top cushion is not
Evaluate this Package Gel Packs loose in top of container PU Foam Cushion
Evaluate this Package No thermal mass on the bottom of the container Leads to a non-uniform thermal condition
Evaluate this Package Thermal Mapping Box 2 Box 2 Bottom Box 2 Middle Box 2 Top Lab (Ambient) 2 C 8 C 35 30 Temperature C 25 20 15 10 5 0-5 0.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 90.00 100.00 110.00 120.00 Time (Hours)
Package Performance Vibration Random Compression Shock Drop, impact Atmospheric Standard performance testing protocols
Good Package Design More insulation the better, right? Insulation costs money, results in higher BOM costs Large Packages are a problem Hard to carry & Difficult to store Increased surface area hurts performance Costly to ship Customer must deal with disposal
Good Package Design Large Thermal Mass Lots of gel packs plus payload Shipping Mostly Water (60lbs/ft 3!) Supplemental items like gel packs, bricks, etc can be expensive These items must be stored at temperature prior to pack out
Thermal Performance Small Insulated Shipper Setpoint +30 C Temperature C 35 30 25 20 15 10 5 0 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 Time (hrs) Small Shipper Vial Small Shipper Core Set Point +2 C +8 C
Thermal Performance Large Insulated Shipper Setpoint +30 C 35 Temperature C 30 25 20 15 10 5 0 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 Time (hrs) Large Shipper Vial Large Shipper Core Set Point +2 C +8 C
Thermal Performance Temperature C 45 40 35 30 25 20 15 10 5 0 Small Insulated Shipper Setpoint +40 C 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 Time (hours) Small Shipper Vial Small Shipper Core +2 C +8 C Set Point
Thermal Performance Temperature C 45 40 35 30 25 20 15 10 5 0 Large Insulated Shipper Setpoint +40 C 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 Time (hours) Large Shipper Vial Large Shipper Core +2 C +8 C Set Point
Thermal Performance Small Insulated Shipper Setpoint +30 C and +40 C 35 30 25 Temperature C 20 15 10 5 0 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 Time (hrs) +30 C Small Shipper Vial Set Point +8 C +40 C Small Shipper Core +30 C Small Shipper Core +2 C +40 C Small Shipper Vial
Closing Thoughts Know your environment Determine the Thermal Mass requirements Design a tight internal package Evaluate the Pack using a data logger Make adjustments
Closing Thoughts Take time to understand the fundamentals of heat transfer Explore Other Configuration Options Get more control over Operations costs Quality Suppliers
Dimensions.07 Conference Thank you Questions?