Metal-sheathed heating elements are electric heating components with a metal tube as the outer shell. Inside, spiral electric heating alloy wires (such as nickel-chromium or iron-chromium alloys) are arranged axially, and the gaps are filled with compacted insulating and thermally conductive magnesium oxide powder. Both ends are sealed with silicone or ceramic. The structure combines heat resistance, thermal conductivity, and insulation, making it suitable for heating air, metal molds, and various liquids.
Structure and Performance
Shell Material: Commonly used metal tubes include titanium, zirconium, and stainless steel (e.g., SUS304/316), offering corrosion resistance and high-temperature durability.
Heating Element: Spiral electric heating alloy wires (e.g., nickel-chromium or iron-chromium alloys) are tightly arranged inside the tube to achieve efficient electric-to-thermal conversion.
Filling Medium: Magnesium oxide powder (MgO) provides both thermal conductivity and insulation, ensuring stable operation.
Sealing Design: Tube ends are sealed with silicone or ceramic to prevent heat loss and extend service life.
Application Scenarios
Industrial Heating: Used for mold co-heating, liquid heating, and heat exchange in sealed containers, such as nitrate tanks, oil tanks, and acid-alkali tanks.
Electrical Equipment: Suitable for high-temperature equipment like drying ovens and hot press molds, with surface power density reaching 1-1.2W/cm2. 

Special Processes: Can be bent into non-standard shapes like U-type or W-type to meet complex heating requirements. 

Core Advantages
High Efficiency: Stable thermal efficiency with high electric energy conversion rate.

Long Lifespan: Designed lifespan generally exceeds 10,000 hours, with some models reaching up to 9,600 hours.
Safety: Supports over-temperature protection devices to ensure stable and reliable operation.