Corrosion-Resistant Alumina Ceramic Washers & Spacers for Chemical Processing Equipment

Alumina Washers Applications

•  Vacuum Equipment Manufacturing

  In high-vacuum (HV) and ultra-high-vacuum (UHV) systems, alumina ceramic washers are used as insulating standoffs for electrical feedthroughs and sample holders.

  ✅Key Advantages

  1. Low Outgassing: Material purity ensures minimal gas release, maintaining vacuum integrity down to 10⁻⁹ Torr.
  2. High Voltage Insulation: Prevents electrical discharge between components inside the vacuum chamber.
  3. Thermal Stability: Withstands bake-out temperatures up to 450°C without deformation.

  ✅ Problem Solved

  A U.S.-based manufacturer of mass spectrometers was experiencing signal noise due to polymer-based insulators outgassing during operation. By replacing them with our 99.8% pure alumina washers, they eliminated the contamination source, reducing signal noise by 15% and improving instrument sensitivity.

• Industrial Heating & Furnace Systems

  These alumina washers serve as electrical insulators and mechanical supports for heating elements in industrial furnaces and heat treatment systems.

  ✅Key Advantages

  1. High-Temperature Strength: Maintains structural integrity and insulating properties at continuous temperatures of 1600°C.
  2. Thermal Shock Resistance: Withstands rapid temperature cycling without cracking.
  3. Precise Positioning: Custom dimensions ensure heating elements are held securely, promoting uniform heat distribution.

  ✅ Problem Solved

  A German furnace builder required insulating spacers that would not degrade after 2,000 hours of operation at 1500°C. Standard ceramic options showed signs of sagging. Our custom 99.5% alumina washers, with a specific thickness tolerance of ±0.05mm, provided the required stability, extending the maintenance interval by 30%.

• Precision Sensor & Instrument Assembly

  Used as insulating spacers and alignment rings in the assembly of pressure sensors, flow meters, and analytical instruments.

  ✅Key Advantages

  1. Dimensional Precision: Tight tolerances (±0.02mm) ensure accurate and repeatable sensor assembly.
  2. Mechanical Rigidity: High compressive strength prevents deformation under load, maintaining sensor calibration.
  3. Electrical Isolation: Isolates the sensing element from the housing to prevent signal interference.

  ✅ Problem Solved

  A UK-based sensor manufacturer faced a 5% rejection rate due to inconsistent alignment of sensing elements. We provided polished alumina ceramic rings with a flatness of <0.01mm. This improved their assembly precision, reducing the final product rejection rate to below 1%.

Alumina Spacers Usage Instructions

Proper handling extends the life of your alumina ceramic washers and reduces operational costs.

• Installation

  1. Handle with clean gloves to avoid surface contamination.
  2. Ensure mating surfaces are clean and free of burrs.
  3. Apply clamping force evenly to avoid stress concentration. Do not overtighten.

• Operation

  1. Avoid mechanical impact, especially at extreme temperatures.
  2. Adhere to the specified maximum service temperature (e.g., 1600°C for 99.5% Al₂O₃).
  3. For rapid heating/cooling, consult our engineers about thermal shock limits for your specific part geometry.

• Storage

  1. Store in the original protective packaging in a dry, clean environment.
  2. Avoid storing with heavy or sharp objects that could cause impact damage.

• Cleaning

  1. Use isopropyl alcohol (IPA) and a lint-free cloth for general cleaning.
  2. For stubborn contaminants, ultrasonic cleaning in a suitable solvent is effective.
  3. Ensure parts are completely dry before installation in a vacuum or high-voltage system.

Alumina Ceramic Washer FAQ

1. Q: Can you machine threads into an alumina ceramic washer?
   A: Yes, we can machine internal or external threads, but this adds complexity and cost. We can review your design for feasibility.
2. Q: What is the difference between 95% and 99.5% alumina ceramic washers?
   A: A 99.5% alumina washer offers higher temperature resistance, better electrical insulation, and superior corrosion resistance compared to a 95% alumina washer.
3. Q: How do you ensure the dimensional accuracy of the washers?
   A: We use precision grinding equipment and verify all critical dimensions with calibrated measurement tools, including CMMs and laser micrometres. A quality inspection report is available.
4. Q: Is there a minimum order quantity (MOQ) for custom washers?
   A: We support prototyping and small-batch production. While there is no strict MOQ, pricing per piece is more favourable for larger quantities.
5. Q: Can these alumina washers be used in UHV (ultra-high vacuum) applications?
   A: Yes, our 99.5% and 99.7% purity alumina washers have very low outgassing rates and are suitable for UHV environments after proper cleaning and bake-out.
6. Q: What surface finish can you achieve on the flat faces of the washer?
   A: We can provide a polished surface with a roughness (Ra) of less than 0.1 micrometres, which is ideal for sealing applications.
7. Q: How does the cost of an alumina ceramic washer compare to one made of Zirconia?
   A: An alumina ceramic washer is generally more cost-effective than a zirconia washer. Zirconia is typically selected for applications requiring higher fracture toughness.
8. Q: Do you stock standard metric sizes like M5 and M6 alumina washers?
   A: Yes, we frequently manufacture and stock alumina ceramic washers designed to be compatible with standard metric hardware, including M5 and M6 screws.
   Here is what that typically means for dimensions:
   1. M5 Alumina Washer: Designed to fit an M5 screw, this washer would have an Inner Diameter (ID) slightly larger than 5mm, commonly ~5.3mm, to provide proper clearance. The Outer Diameter (OD) and Thickness can vary, with common ODs being 10mm or 12mm.
   2. M6 Alumina Washer: To fit an M6 screw, this washer would have an Inner Diameter (ID) of approximately ~6.4mm. Common Outer Diameters are often 12mm or 16mm, though this can be customized.

Hear From Our Clients about Alumina Ceramic Washer

• ⭐️⭐️⭐️⭐️⭐️
  The custom alumina washers we ordered from the Adcerax factory had a dimensional tolerance that was spot-on. Our assembly process is now much smoother. The engineering support during the design phase was invaluable.
  -- David Schmidt, Lead Engineer, a German Vacuum Technology company
• ⭐️⭐️⭐️⭐️⭐️
  We needed high-temperature insulating rings for a new furnace design. The parts we received have performed flawlessly at 1500°C. The quality is consistent across the entire batch.
  -- Sarah Jenkins, R&D Manager, a US-based Industrial Heating solutions provider
• ⭐️⭐️⭐️⭐️⭐️
  Switching to the Adcerax supplier's alumina ceramic spacers solved our sensor alignment problem. The surface finish was exactly as specified. Excellent product and reliable delivery.
  -- Kenji Tanaka, Production Supervisor, a Japanese Precision Instruments firm
• ⭐️⭐️⭐️⭐️⭐️
  We ordered a small batch of 20 custom alumina ceramic washers for a prototype. The process was straightforward, and the parts were delivered faster than expected. We will be placing a larger order.
  -- Maria Rossi, Scientist, a UK-based Research Institute