Cartridge Heater Selection Guide

**Subtitle**: Choosing the Right High-Density Heater for Your Application

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Introduction

**Cartridge heaters**, also known as rod heaters or single-end heaters, are among the most versatile heating elements in industrial applications. Unlike tubular heaters with dual terminals, cartridge heaters have both leads at one end, making them ideal for deep-hole heating, mold heating, and various liquid heating applications.

This guide covers cartridge heater types, selection methods, and typical applications.

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Part 1: Cartridge Heater Basics

1.1 What is a Cartridge Heater

Cartridge heaters feature:

· - **Single-end termination**: Power and thermocouple leads exit from one end

· - **High watt density**: Up to 50 W/cm² power density

· - **High temperature**: Maximum operating temperature up to 800°C

· - **Multiple sheath materials**: 304/316/321 SS, Incoloy 800

1.2 Core Components

| Component | Material Options | Function |

|-----------|-----------------|----------|

| Sheath | 304/316/321/Incoloy | Protection, heat transfer |

| Resistance wire | NiCr alloy | Heating element |

| Magnesium oxide | Electrical grade MgO | Insulation, conduction |

| Terminals | SS/Ceramic | Electrical connection |

| Seals | Silicone rubber/Ceramic | Moisture sealing |

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Part 2: Cartridge Heater Types

2.1 By Watt Density

| Type | Watt Density | Max Temp | Typical Use |

|------|-------------|----------|-------------|

| Standard | 5-10 W/cm² | 300°C | Water, oil heating |

| Medium-high | 10-20 W/cm² | 500°C | Mold heating, air |

| High power | 20-35 W/cm² | 700°C | Rapid heating |

| Ultra-high | 35-50 W/cm² | 800°C | Special high-temp |

2.2 By Sheath Material

| Material | Max Temp | Corrosion | Best For |

|----------|----------|-----------|----------|

| 304 SS | 400°C | General | Water, oil |

| 316 SS | 450°C | Good | Weak acid/base |

| 321 SS | 600°C | General | High-temp air |

| Incoloy 800 | 800°C | Excellent | High-temp corrosive |

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Part 3: Selection Calculations

3.1 Power Formula for Liquid Heating

P = (V x ρ x c x ΔT) / (t x 860)

V = liquid volume (m³)

ρ = density (kg/m³)

c = specific heat (kJ/kg·K)

ΔT = temperature rise (°C)

t = heating time (h)

3.2 Quick Reference Table

| Application | Watt Density | Sheath | Diameter |

|------------|-------------|--------|----------|

| Injection mold | 15-25 W/cm² | 321 SS | 8-16mm |

| Die casting | 20-30 W/cm² | Incoloy | 10-20mm |

| Water tank | 3-5 W/cm² | 304 SS | 8-12mm |

| Heat transfer oil | 5-8 W/cm² | 304/316 | 10-16mm |

| Air heating | 8-15 W/cm² | 321 SS | 8-16mm |

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Part 4: Installation and Maintenance

4.1 Installation Steps

1. 1. Check hole diameter, depth, surface finish

2. 2. Clean hole thoroughly

3. 3. Apply thermal paste

4. 4. Insert heater gently to full depth

5. 5. Secure lead end

6. 6. Connect wiring, verify voltage

7. 7. Test at low power first

4.2 Common Failures

| Failure | Cause | Solution |

|---------|-------|----------|

| No heat | Internal open | Replace |

| Slow heating | Scale/poor fit | Descale/reinstall |

| Local overheating | Deformed hole | Repair hole |

| Ground fault | Insulation failure | Replace |

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Conclusion

Proper selection and installation ensure optimal heater performance.

**BANBEKE** offers complete cartridge heater solutions:

· - Diameters: 6mm to 25mm

· - Power: 100W to 5000W

· - Materials: 304/316/321/Incoloy 800

· - Built-in thermocouple option

**BANBEKE Industrial Heaters**

· - Website: senxte.com