Custom ceramic insulation parts include tubes, sleeves, washers, spacers, bushings, plates, blocks, sensor supports and furnace fixtures. Many are made from alumina because it combines electrical insulation, heat resistance and stable production cost.
Common Applications for Ceramic Insulators
- Electrical insulation tubes and sleeves for wires, rods and heating elements.
- Ceramic washers, spacers and bushings for machinery and fixtures.
- High-temperature supports for furnace, welding and thermal equipment.
- Sensor, thermocouple and instrument insulation parts.
- Wear-resistant insulating components in automation and industrial systems.
Why Alumina Is Often Used for Insulation Parts
Alumina ceramic is a common choice for custom insulators because it provides good electrical insulation, hardness, dimensional stability and high-temperature performance. It can be formed and machined into tubes, washers, plates and complex OEM shapes.
For many industrial applications, alumina is more cost-effective than zirconia when the main job is insulation rather than impact toughness.
Design Details That Affect Performance
Insulator failure is often caused by design details rather than material name alone. Sharp inside corners, thin walls, unsupported long tubes or overly tight press fits can create stress in a brittle ceramic part.
Material Property Comparison
| Material | Hardness | Fracture toughness | Flexural strength | Max use temperature | Thermal conductivity | Electrical insulation | Relative cost |
|---|---|---|---|---|---|---|---|
| 95%-99% alumina (Al2O3) | 12-20 GPa | 3-5 MPa m^0.5 | 300-450 MPa | 1500-1700 C | 20-35 W/m K | Excellent | Low to medium |
| 99.5%-99.7% alumina | 16-20 GPa | 3-4 MPa m^0.5 | 300-400 MPa | 1600-1700 C | 25-35 W/m K | Excellent | Medium |
| Y-TZP zirconia (ZrO2) | 11-13 GPa | 6-10 MPa m^0.5 | 800-1200 MPa | 900-1100 C | 2-3 W/m K | Good at room temperature | Medium to high |
Typical values for comparison — request a datasheet for guaranteed specifications.
Wall thickness and hole size
For tubes and bushings, the ratio between outside diameter and inside diameter matters. Very thin walls can be difficult to sinter, grind and handle. If space allows, a slightly thicker wall can improve yield and reduce cost.
Mounting and assembly
Ceramic parts are strong in compression but sensitive to concentrated impact or bending. If the insulator is clamped, pressed or bonded into an assembly, the mounting method should be reviewed before production.
Surface finish
Some insulation parts only need standard fired or ground surfaces. Others need polished surfaces for sliding contact, sealing or easy cleaning. Only critical surfaces should be specified as polished to control cost.
Information Needed for a Ceramic Insulator Quote
- Drawing, sketch or sample photo.
- Voltage, temperature and working environment.
- Material preference, commonly alumina for insulation.
- Dimensions, tolerance, quantity and surface finish.
- How the part is mounted or assembled.
Custom Ceramic Insulators From HERUN
HERUN Ceramics manufactures custom alumina insulation components from drawings and sample photos. If you only know the application, send the working condition and dimensions; we can help confirm whether an alumina tube, washer, plate, spacer or custom insulator is the right starting point.
FAQ
What ceramic material is commonly used for electrical insulators?
Alumina is commonly used because it combines electrical insulation, heat resistance, hardness and stable production cost for custom tubes, washers, spacers and bushings.
What information is needed to quote a ceramic insulator?
A drawing or sample photo, voltage, temperature, dimensions, tolerance, quantity and mounting method help confirm the correct ceramic material and manufacturing route.
Can ceramic insulators be customized for high-temperature equipment?
Yes. HERUN can manufacture custom alumina insulation parts for furnace, welding, sensor and heating equipment when dimensions and working conditions are provided.