What materials are commonly used in cartridge heaters?
Cartridge heaters are designed for high-performance heating in various industrial applications. The choice of materials used in cartridge heaters impacts their durability, efficiency, and suitability for different environments. Here are some commonly used materials:
1. Heating Element Materials
Nickel-Chromium (NiCr): This is one of the most common materials for heating elements due to its high resistance to oxidation and ability to maintain its properties at elevated temperatures. NiCr alloys are used for general-purpose heating.
Kanthal: A trademarked material that is an alloy of iron, chromium, and aluminum. Kanthal is known for its high-temperature stability and resistance to oxidation, making it suitable for very high-temperature applications.
2. Insulation Materials
Magnesium Oxide (MgO): Magnesium oxide is frequently used as insulation material in cartridge heaters. It provides excellent thermal conductivity and electrical insulation, which helps in efficient heat transfer and safety.
Ceramic: In some high-temperature applications, ceramic insulation is used due to its high heat resistance and insulation properties.
3. Outer Sheath Materials
Stainless Steel: Stainless steel is commonly used for the outer sheath of cartridge heaters due to its resistance to corrosion, oxidation, and high temperatures. It is ideal for most general applications.
Incoloy: This is a nickel-iron-chromium alloy known for its excellent resistance to high temperatures and corrosion. It is often used in extreme environments and for high-temperature applications.
4. Terminals and Connectors
Copper: Copper is frequently used for electrical terminals and connectors due to its excellent electrical conductivity.
Brass: Brass is also used for terminals and connectors because it provides good conductivity and resistance to corrosion.
5. Sealing Materials
Silicone: Silicone is used in some heaters for sealing and insulating purposes due to its high-temperature resistance and flexibility.
Epoxy Resins: Epoxy resins are sometimes used to seal and protect the heater components from environmental factors.
