| Author: IMS |
| Calculating Barrel Heat Loss |
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 Barrel
insulation contains and conserves costly barrel heat. Given the price of energy
today, it is wise to consider the many benefits that proper barrel insulation
can provide.
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Cuts energy use — increases profits
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Payback is generally 6-12 months
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Promotes faster machine start-ups
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Stops barrel heat fluctuations — ensures consistent part quality
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Protects heater bands from trouble-causing drool and debris
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Helps create a cooler work environment
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Safeguards personnel from accidental burns
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The table below can help you estimate your barrel heat loss and estimate yearly
savings in energy costs.
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Operating
Temperature (°F) |
No Insulation
(Watts/Sq. Ft.) |
1" Insulation
(Watts/Sq. Ft.) |
1.5" Insulation
(Watts/Sq. Ft.) |
| 300 |
180 |
18.6 |
12.4 |
| 325 |
210 |
20.9 |
14.0 |
| 350 |
243 |
23.4 |
15.6 |
| 375 |
275 |
26.0 |
17.3 |
| 400 |
313 |
29.0 |
19.0 |
| 425 |
350 |
31.5 |
21.0 |
| 450 |
387 |
34.3 |
22.9 |
| 475 |
425 |
37.2 |
24.8 |
| 500 |
465 |
40.1 |
25.8 |
| 525 |
505 |
43.2 |
26.9 |
| 550 |
550 |
46.5 |
28.3 |
| 575 |
605 |
49.9 |
29.9 |
| 600 |
660 |
54.1 |
32.1 |
| Note: Heat loss values are based on an ambient room
temperature of 70° F. Values are based on indoor installation with no wind
using ceramic insulation. |
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| Barrel Heat Loss Sample Problem |
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Barrel Length: 48"
Barrel Diameter: 6-1/2"
Barrel Dimensions: 48" l x 6-1/2" dia.
Surface Area: 6.8 sq. ft.
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| Heat Loss: |
At 450° with no insulation: 387 watts/sq. ft.
At 450° with 1" ceramic insulation: 34.3 watts/sq. ft.
387 watts/sq. ft. x 6.8 sq. ft. = 2632 watts heat loss with no insulation
34.3 watts/sq. ft. x 6.8 sq. ft. = 233 watts heat loss with insulation |
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| Savings: |
| 2632 watts without insulation -233 watts with insulation |
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= |
2.40 kwh savings |
| 1000 w/kw |
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2.40 kwh savings x $.05/kwh x 24 hours x 5 days/week
x 4.3 weeks/month x 12 months = $743.04 savings per year |
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| Products related to this article: |
 Barrel Insulation Stock Sizes and Pricing
 Custom
Made Uni-Vest™ Form (pdf) |
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| Uni-Vest™ Installation Instructions |
Installation
- Remove any resin from heaters and barrel external surfaces.
Important: All heater electrical wire needs to be high temperature – 900°F
- Strap blankets on snugly, but not tight. Do not pull straps tight.
- Ensure no mechanical devices rub the blankets
- Exit lead wires from heater bands out the overlap or side of the blanket
- Injection molders: Install segment blankets starting at the rear of the machines hopper end and work towards the front of the barrel.
Removal
- Remove blankets from the barrel with care. Sharp objects may tear inside fabric.
Important Information
- Interior fabric, cream color, is rated for 2000° F
- Exterior Fabric, green or blue in color, is rated for 500° F
- Blanket warranty is for 5 years under normal operating conditions
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