Cast-In Heater Specifications and Tolerances
Casting Alloys
| Casting Alloy | Aluminum | Copper | Silicone | Zinc | Lead | Maximum Iron | Tin | Other |
|---|---|---|---|---|---|---|---|---|
| Aluminum 319 | 85.8 – 91.58% | 3.0 – 4.0% | 5.50 – 6.50% | ≤ 1.0% | — | ≤ 1.0% | — | ≤1.7% |
| Aluminum 356 | 90.1 – 93.3 % | ≤0.25% | 6.50 – 7.50% | ≤0.35% | — | ≤0.60% | — | ≤1.125% |
| Bronze | 9.0 – 11.0% | ≥ 86.0% | — | — | — | 0.80 – 1.50% | — | ≤1% |
| Yellow Brass | ≤0.55% | 58.0 – 64.0% | ≤0.05% | 32.0 – 40.0% | 0.80 – 1.50% | ≤0.70% | 0.50 – 1.50% | ≤1% |
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Material Properties
| Material | Classification | Max. Surface Temperature | Density | Coefficient of Linear Thermal Expansion | Specific Heat Capacity | Thermal Conductivity | Melting Point |
|---|---|---|---|---|---|---|---|
| °F (°C) | (lb/in3) | (in/in/°F × 10-6) | (BTU/lb-°F) | (BTU-in/hr-ft2-°F) | (°F) | ||
| Aluminum 319 | Aluminum 319.0 | 700 (371) | 0.101 | 12.7 @ 68° – 572°F | 0.23 | 754 | 960 – 1120 |
| Aluminum 356 | Aluminum 356.0 | 750 (399) | 0.0968 | 12.9 @ 68° – 572°F | 0.23 | 1160 | 1030 – 1140 |
| Bronze | UNS C95300 | 1350 (732) | 0.272 | 9 @ 68° – 572°F | 0.0896 | 437 | 1900 – 1913 |
| Yellow Brass | UNS C85700 | 1200 (649) | 0.304 | 12.2 @68° – 500°F | 0.0899 | 582 | 1660 – 1690 |
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Minimum Casting Thickness vs. Heating Element and/or Cooling Tube Diameters
| Casting Thickness | Maximum Available Element Diameter | Maximum Available Cooling Tube Diameter | Maximum Element and Cooling Tube Combination |
|---|---|---|---|
| Heat Only | Cool Only | Heat and Cool | |
| Finned Casting | |||
| 5/8″ (15.9 mm) | 0.26 | 1/4 | — |
| 3/4″ (19.1 mm) | 0.375 | 3/8 | — |
| 1″ (25.4 mm) | 0.43 | 1/2 | — |
| 1-1/4″ (31.8 mm) | 0.43 | 1/2 | .260 and 3/8 |
| 1-3/8″ (34.9 mm) | 0.43 | 1/2 | .315 and 1/2 |
| 1-1/2″ (38.1 mm) | 0.43 | 1/2 | .430 and 1/2 |
| 1-5/8″ (41.3 mm) | 0.43 | 1/2 | .430 and 1/2 |
| 1-3/4″ (44.5 mm) | 0.43 | 1/2 | .430 and 1/2 |
| 3/4″ (19.1 mm) | 0.375 | — | — |
| 7/8″ (22.2 mm) | 0.43 | — | — |
| 1″ (25.4 mm) | 0.43 | — | — |
| 1-3/4″ (44.5 mm) | 0.43 | — | — |
Linear Thermal Expansion Formula:
∆ L = Li × α × (Tf – Ti) × 10-6
∆ L = Change in Length Li = Initial Length
α = Coefficient of Linear Thermal Expansion
Tf = Final Temperature
Ti = Initial Temperature
Heating Element Electrical Specifications
| Tubular Heater Diameter | .260″ | .315″ | .375″ | .430″ |
| Maximum Volts | 240 | 277 | 480 | 600 |
| Maximum Amps Per Element | 15 | 30 | 40 | 40 |
| Maximum Watt Density: | ||||
| Aluminum Alloy | 35 W/in2 on the element | |||
| Bronze or Brass | 45 W/in2 on the element | |||
| Resistance Tolerance: | +10%, −5% Wattage Tolerance: +5%, −10% | |||
| Three Phase available depending on casting size. | ||||
| Ground Studs can be added to most cast-ins. | ||||
Note: Tempco-Pak mineral insulated cable heaters can be used in place of tubular heating elements to fit physical constraints not possible with conventional heating elements. See catalog Section 5 for more details.
Cooling Tube Materials for Castings with Liquid Cooling
| Tube Material | Tube OD and Wall Thickness |
|---|---|
| Stainless Steel (Standard) | 1/4″ O.D. × .028 wall |
| Stainless Steel (Standard) | 3/8″ O.D. × .035 wall |
| Stainless Steel (Standard) | 1/2″ O.D. × .049 wall |
| Stainless Steel (Optional) | 5/8″ O.D. × .049 wall |
| Incoloy® 840 (Optional) | 1/2″ O.D. × .049 wall |
| Tubing with heavier wall thickness is available upon request. | |
Casting Size & Weight Limitations
| Cylindrical | Platen | |
|---|---|---|
| Minimum Inside Diameter: | 1″ (25.4 mm) | — |
| Maximum Inside Diameter: | 48″ (1219 mm) | — |
| Minimum Width: | — | 1-1/2″ (38.1 mm) |
| Maximum Width: | — | 60″ (1524 mm) |
| Minimum Length: | 1-3/4″ (44.5 mm) | 4″ (102 mm) |
| Maximum Length: | 40″ (1016 mm) | 72″ (1829 mm) |
| Finish: | 125 RMS Standard or to customer spec. | |
| Gap (two-piece cylindrical cast-in band heaters): | >1/4″ (6.4 mm) top and bottom or to customer specification | |
| Maximum Weight: | ||
| Aluminum | 600 pounds | |
| Bronze & Brass | 300 pounds | |
NOTES: Cylindrical heaters are made with two half-round heaters. Cast-In thermal components can be made in any practical size, weight and geometric shape.
Options for Cast-In Thermal Components
Casting Surface Treatments Special surface finishes are required in some applications:
- Electroless Nickel Plating
- Anodizing
- Teflon®
- Hard-Coat Anodizing
- Magnaplate
Lab Services:
- Computerized Infrared Heating Profiles
- Life Cycle Testing
- X-Rays to confirm heating element location and casting density
- Heating Ramp Rate Testing
Agency Approvals:
Cast-In Heater Elements are UL recognized under UL File Number E90771.
If you require UL Agency Approval, please specify when ordering.
