Made from 99% high-purity alumina (Al₂O₃) ceramic with a dense, low-porosity structure.
Electrical equipment, high-voltage insulation systems, heating equipment, vacuum devices, semiconductor fixtures, laser equipment, precision instruments, and electronic assemblies.
Standard sizes usually take 10–20 days. For custom dimensions, tight tolerances, special surface finishes, or complex structures, the delivery time will be confirmed based on your drawings, quantity, and processing requirements. You can also send us your drawing for a quick review.
The 99% Alumina Ceramic Insulating Tube is a precision electrical ceramic insulator made from high-purity alumina ceramic. It is used in industrial heaters, high-voltage equipment, vacuum systems, laser equipment, and electronic assemblies. Its dense ceramic structure provides electrical isolation, high-temperature resistance, and mechanical protection, helping prevent current leakage and component damage under demanding operating conditions.
Material System
This product is made from 99% high-purity alumina (Al₂O₃) ceramic with a dense, low-porosity structure, making it suitable for applications requiring high material purity and cleanliness. For general industrial insulation and cost-sensitive projects, consider our 96% alumina ceramic sleeve.
For applications that require a more cost-effective sleeve or bushing for general mechanical use, you may also view our 96% alumina ceramic sleeve / bushing.
This 99% alumina ceramic sleeve is suitable for equipment where insulation stability, heat resistance, and dimensional reliability are important. It can be customized for different electrical, thermal, vacuum, and precision assembly requirements.
For thermocouple-related applications, you may also check our alumina ceramic insulator for Type K thermocouple sensors or our 99% high-purity multi-bore alumina thermocouple insulator tube.
The following data is for reference only. Actual performance may vary depending on part size, structure, processing method, and operating conditions.
| Parameter | Typical Value |
|---|---|
| Material Content | ≥ 99% Al2O3 |
| Dielectric Strength | 18–22 kV/mm |
| Volume Resistivity | > 1014 Ω·cm @ 20°C |
| Max Service Temperature | Up to 1650°C |
| Thermal Conductivity | 30–33 W/(m·K) |
| Density | 3.85–3.92 g/cm³ |
| Dielectric Constant | 9.6–10.1 @ 1 MHz |
| Hardness | Approx. 18 GPa |
1. What is the primary function of a 99% alumina ceramic sleeve?
It is used to isolate, separate, support, or protect conductive and mechanical components inside equipment. Its exact function depends on the sleeve dimensions, assembly structure, and operating conditions.
2. What is the difference between 99% and 96% alumina ceramic sleeves?
99% alumina provides higher material purity and is generally selected for applications with stricter requirements for high-temperature insulation, chemical stability, vacuum compatibility, or cleanliness. 96% alumina is a more economical option for general industrial use.
3. Which dimensions and structural features can be customized?
The inner diameter, outer diameter, length, wall thickness, chamfers, grooves, steps, holes, tolerances, and surface finish can be manufactured according to customer drawings or samples.
4. How is the voltage-withstand capability of the sleeve determined?
Voltage-withstand capability depends on the material grade, wall thickness, sleeve length, surface condition, creepage distance, assembly design, and operating environment. Please provide the required voltage and installation details for evaluation.
5. Is the sleeve suitable for vacuum or clean equipment?
Dense 99% alumina ceramic can be used in selected vacuum and clean-equipment assemblies. The material grade, machining process, cleaning method, and permissible outgassing level should be confirmed according to the application.
6. Is this the same as a thermocouple ceramic protection tube?
No. This product is a general-purpose insulating ceramic sleeve. A thermocouple protection tube is designed specifically to house or protect thermocouple elements and may require different end structures, bore configurations, dimensions, and temperature ratings.
7. What information is required for a quotation?
Please provide the drawing or sample, material purity, dimensions, tolerances, quantity, operating temperature, voltage requirement, surface finish, installation method, and application environment.
