Core Value

High Temperature Industrial MgO Ceramic Insulator Tubes engineered for high-watt-density cartridge heaters, thermocouples, and precision industrial heating elements. Backed by 30+ years of industrial manufacturing experience, our fused high-purity Magnesium Oxide (MgO) ceramic tubes deliver superior thermal conductivity, exceptional dielectric strength, and extreme electrical insulation at elevated temperatures. Designed for operating temperatures up to 1200°C (2192°F) with single, double, or multi-bore geometry. Every batch undergoes multiple rigorous quality checks to ensure precise dimensional tolerances, high compaction density, and zero internal cracking. OEM/ODM customization available with 24-hour rapid quoting.

High Temperature Industrial MgO Ceramic Tube Selection Guide

Select the optimal MgO insulator core configuration based on heating wire count, sheath dimensions, and element density:

• Single-Hole MgO Ceramic Tubes: High-Purity Fused MgO, Single Bore Core, Outer Diameter 2.0 mm – 25.0 mm, Inner Diameter 0.8 mm – 10.0 mm. Designed for single-lead heating rods, internal resistance cores, and high-voltage probes.

• Double-Hole MgO Ceramic Tubes: High-Density MgO Formula, 2-Bore Symmetrical, Outer Diameter 2.5 mm – 30.0 mm, Hole Diameter 0.5 mm – 6.0 mm. Ideal for U-shaped heating coils, loop-back resistance wires, and standard cartridge heaters.

• 4-Hole & Multi-Bore MgO Tubes: Precision-Extruded MgO Matrix, 4-Bore to 6-Bore Layout, Outer Diameter 3.0 mm – 35.0 mm, Hole Diameter 0.5 mm – 4.0 mm. Engineered for dual-circuit cartridge heaters, multi-point thermocouples, and complex sensor probes.

• Custom Grooved & Crushed MgO Cores: High-Purity Fused Core, External Spiral/Straight Grooves, Customized Length & Pitches. Built for specialized internal heating wire winding and high-density swaging processes.

Material Performance: High-Purity MgO Ceramic vs. Alumina Ceramic

Understanding material characteristics ensures proper core material selection for internal heating element manufacturing:

• Thermal Conductivity: High-Purity Fused MgO Core delivers ultra-high thermal heat transfer to sheath | Alumina Ceramic provides moderate thermal transfer rate

• Electrical Insulation at High Temp: MgO Ceramic Core retains exceptional volume resistivity at 1000°C+ | Alumina Ceramic exhibits declining insulation under extreme watt densities

• Swaging & Compaction Capability: MgO Ceramic Core crushes evenly into uniform insulating powder during swaging | Alumina Ceramic is rigid and difficult to compact inside metal sheaths

• Continuous Working Temp: Fused High-Purity MgO up to 1200°C (2192°F) | Standard Industrial Alumina up to 800°C – 1000°C

• Best Used For: MgO Ceramic Tubes are purpose-built for cartridge heaters, tubular heating elements, and thermocouples | Alumina Ceramic is preferred for external structural insulation, terminal blocks, and furnace tubes

Technical Specifications & Electrical Performance

• Chemical Composition: 96% to 99% High-Purity Fused Magnesium Oxide (MgO). Low iron (Fe₂O₃ ≤ 0.05%) and low boron content to prevent electrical leakage.

• Continuous Temp Rating: Continuous operation up to 1200°C. Maintains integrity without softening or thermal degradation.

• Volume Resistivity: ≥ 10¹⁰ Ω·cm at room temperature; ≥ 10⁶ Ω·cm at 800°C. Prevents high-voltage flashover and current leakage.

• Thermal Conductivity: ≥ 30 W/(m·K) at room temperature, facilitating ultra-fast heat dissipation from resistance wire to metal sheath.

• Dimensional Tolerance: Outer diameter tolerance controlled within ± 0.05 mm to ± 0.10 mm; hole pitch precision within ± 0.03 mm.

• Manufacturing Provenance: Backed by 30+ years manufacturing experience in precision ceramic extrusion and high-purity MgO pressing.

• Quality Assurance: Every batch undergoes multiple rigorous quality checks, including high-voltage insulation tests, density verifications, and thermal shock testing.

• Certifications: ISO 9001, RoHS, REACH compliance documentation. Full Certificate of Analysis (COA) included with every order.

Key Engineering Advantages for Industrial Applications

• Ultra-High Thermal Transfer: Accelerates heat conduction from internal NiCr/FeCrAl heating wires to the outer metal sheath, extending heating element lifespan.

• Superior Dielectric Isolation: High dielectric breakdown strength prevents internal short circuits between resistance coils and metal tubing walls.

• Optimized Swaging Performance: Engineered grain structure ensures uniform crushing under high-pressure swaging machines without wire migration.

• High Chemical & Thermal Stability: Inert to high-temperature oxidation and immune to chemical breakdown under intense thermal cycling.

• 30+ Years Precision Manufacturing: 30+ years of specialized production experience guarantees tight hole concentricity and smooth bore surfaces for easy wire insertion.

Industrial Applications & Compatible Equipment

• High-Watt-Density Cartridge Heaters: Essential internal core insulator for plastics machinery, mold heating, and packaging sealers.

• Thermocouples & Temperature Sensors: Provides precise multi-bore wire separation for Type K, J, E, and T thermocouple probes.

• Hot Runner Systems & Injection Molds: Delivers heat-resistant core insulation for runner nozzles and manifold heating rods.

• Industrial Electric Heating Tubes: Used in immersion heaters, air preheaters, and high-temperature radiant heating elements.

HT-Heater vs Standard Market Heaters

Step-by-Step Installation & Wiring Guidelines

• 1. Moisture Prevention: Store MgO ceramic tubes in a dry environment or heated cabinet; MgO is hygroscopic and must be kept moisture-free prior to assembly.

  2. Resistance Wire Threading: Insert coiled or straight resistance wire through the designated single/multi-bore channels carefully to avoid mechanical scraping.

  3. Sheath Insertion: Place the wire-loaded MgO insulator tube into the stainless steel or Incoloy outer sheath.

  4. Swaging / Reducing Process: Pass the assembled tube through a rotary swaging machine or tube reducer to compress the MgO tube into a dense, solid insulation powder.

  5. Final Bake-Out & Sealing: Heat the finished element to remove any trace moisture and apply high-temperature epoxy or ceramic sealants at the lead ends.

Customer Success Stories

• Cartridge Heater Manufacturer (USA): Element burnout rates reduced by 40%. “Switching to HT-Heater high-purity MgO ceramic tubes significantly improved our swaging compaction density. HT-Heater undergoes multiple rigorous quality checks, ensuring zero wire displacement.”

• Sensor & Thermocouple OEM (Japan): Production throughput increased by 25%. “30+ years manufacturing experience is obvious in their tight hole tolerances. Our automated wire threading machines run smoothly without jamming.”

Frequently Asked Questions (Technical FAQ)

• Q1: Why is high-purity MgO preferred over alumina for cartridge heater cores? A: MgO (Magnesium Oxide) has significantly higher thermal conductivity than alumina and crushes predictably into dense powder during swaging, ensuring efficient heat transfer from the coil to the outer sheath.

  Q2: How do you prevent MgO ceramic tubes from absorbing atmospheric moisture? A: We ship all MgO insulator tubes in vacuum-sealed moisture-proof packaging with desiccant packs. Pre-assembly baking at 150°C–200°C is recommended if tubes are exposed to ambient air for extended periods.

  Q3: Can HT-Heater produce custom multi-bore MgO tubes according to drawing specs? A: Yes, we customize outer diameters, inner bore diameters, hole counts (1 to 6 holes), and custom overall lengths based on your technical CAD drawings.

Custom OEM Solutions & Ordering Process

• MOQ & Samples: Standard dimensions available in stock (MOQ 100 pcs). Custom extruded tooling delivered in 7–12 business days.

• Quality & Documentation Provided: Certificate of Analysis (COA), Dimensional Inspection Reports, and High-Temp Insulation Test Data included with every shipment.

• Inquiry Checklist: Please specify Outer Diameter (OD), Inner Hole Diameter (ID), Number of Holes, Length (mm), MgO Purity (96%/99%), and Quantity when requesting a quote.

Global Certifications & Compliance

• CE Marking
  Fully compliant with European safety and environmental standards.
• LVD Compliance
  Low Voltage Directive tested for continuous thermal load safety.
• RoHS Compliant
  Constructed using environmentally safe, lead-controlled brass alloys.
• ISO 9001
  Certified quality control covering CNC machining, coil pressing, and electrical testing.

Quality Documentation: Certificate of Conformity (COC) and insulation resistance test reports included.

Comprehensive After-Sales Support

• • Warranty: 1-Year Comprehensive Warranty covering internal heating element and built-in sensor.

  • Technical Support: Application engineers available for wattage distribution calculation, thermocouple calibration, and nozzle fitting assistance.

  • Global Response Network: BACKED BY 30+ YEARS MANUFACTURING EXPERIENCE with technical inquiry feedback within 2 hours.

Ready to Optimize Your Injection Molding?

Next Steps:

• 📧 Request Custom Quote – Send your nozzle dimensions, wattage, voltage, and HT-CLW-450 drawing requirements.
• 🔧 Free Design Consultation – Work with our thermal engineers to optimize heat distribution and lead insulation.
• 📦 Order Test Samples – Evaluate thermal performance on your injection molding machine.
• 📞 Contact Hot Runner Experts – Response within 2 hours

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