Alumina Square Ceramic Tubes for Cartridge Fuses

Cartridge fuses are the "safety guards" of circuit systems, and the alumina ceramic tube serves as the armor, skeleton, and arc extinguishing chamber of this guard. Its performance directly determines the fuse's interrupting capacity, safety, and reliability.

The operating principle of a cartridge fuse is that when a current overload occurs, the internal fuse element (melt) melts and generates an arc, which ultimately extinguishes the arc and interrupts the circuit. The excellent insulation and arc resistance, high mechanical strength and impact resistance, and excellent thermal stability and thermal conductivity of the alumina ceramic tube (Al₂O₃) perfectly meet all the requirements of this demanding process.

Alumina ceramic tubes are widely used in various types of cartridge fuses:
Low-voltage fuses:

• Small cartridge fuses: Used in electronics, instruments, and household appliances (e.g., fuse tubes).
• Industrial fuses: Such as NH knife-type fuses.

High-voltage fuses:

• Current-limiting fuses: Used to protect transformers, capacitors, and other applications, with voltages up to 36 kV and above. This is one of the applications that places the highest demands on ceramic tube performance.
• Drop-out fuses: Commonly used in outdoor overhead lines, their core insulation tubes are also made of alumina ceramic.

Special application fuses:

• Fast-acting fuses for semiconductor protection: Require extremely fast response and strong breaking capacity, placing the highest demands on the ceramic tube's arc resistance and impact resistance.
• New energy vehicle high-voltage fuses: Used to protect battery packs and electric drive systems, operating at voltages up to 1000 V DC, a rapidly growing emerging market.
• Photovoltaic DC fuses: DC arcs are more difficult to extinguish, placing stringent demands on the performance of the ceramic tube.

Our Services

Available materials: Alumina(95%-99.9%), Zirconia(YSZ/Y-TZP, Mg-PSZ, ZTA), Silicon Carbide(SiC), etc.
Customized: Can be custom for special sizes and shapes.
1. Factory price and shipment within 24 hours if in stock.
2. MOQ: Generally 1-5 pieces, depending on size.
3. Payment Terms: PayPal; T/T; L/C, etc.
4. Shipment: By sea, by air, by courier, by post, etc.

Our Processing Capabilities

• Dimensional Accuracy: Up to 0.001mm
• Surface Roughness/Finish: Up to Mirror Finish, can be Glazed,Polished and Metallized
• Concentricity: Up to 0.003mm
• Parallelism: Up to 0.002mm
• Inner Hole Tolerance: Minimum Machinable Size 0.005mm
• Straight Groove: Narrowest Machinable Groove 0.1x100mm
• Thickness: Minimum Machinable Size 0.08mm
• Thread: Minimum Machinable Internal Thread M2, External Threads Unlimited
• Cylindricity: Up to 0.004mm
• Linearity: Up to 0.001mm
• Minimum Hole Diameter: Minimum Machinable Size 0.07mm