Product Specification

Sapphire Through-Hole Bearing – Custom Precision Optical Bearings

The Sapphire Through-Hole Bearing is a high-precision, wear-resistant, and optically stable component engineered for demanding motion-control and micro-mechanical systems. Leveraging single-crystal sapphire’s exceptional hardness and chemical stability, these custom bearings offer long-term durability, ultra-smooth rotation, and outstanding performance in harsh or high-cleanliness environments.

Our factory provides fully customized through-hole sapphire bearings, covering hole size, outer diameter, thickness, chamfering, accuracy grades, and surface finish to meet the requirements of optical instruments, high-speed spindles, measuring devices, and semiconductor equipment.

Product Features

1. Superior Hardness & Wear Resistance

Sapphire ranks 9 on the Mohs scale, allowing it to maintain dimensional accuracy and a polished surface even under continuous friction, high load, or prolonged operation.

2. Ultra-High Dimensional Precision

Tight tolerances can be achieved with CNC machining, precision lapping, and ultrasonic drilling:

• Hole diameter tolerance: ±0.005–0.02 mm

• Cylindricity down to 0.01 mm

• Surface roughness (Ra): < 0.02 μm

This ensures exceptionally smooth rotational performance.

3. Excellent Chemical & Thermal Stability

Sapphire maintains mechanical properties under extreme conditions:

• Temperature resistance: 1,000°C+

• Acid/alkali resistance

• No deformation, no micro-wear particle shedding

Ideal for cleanroom, optical and semiconductor applications.

4. Customizable Geometry

We support custom specifications:

• Through-hole size

• Outer diameter & thickness

• Countersinks, bevels, special shapes

• Polished, matte, or dual-finish surfaces

• Optional metallization or bonding interface

Manufacturing Technology

Precision Drilling (Ultrasonic Drilling / Laser Drilling)

Creates smooth, vertical through-holes with minimal chipping and tight dimensional control.

Double-Side Lapping & Polishing

Ensures flatness, parallelism, and surface roughness meeting optical-grade requirements.

CNC Profiling & Chamfering

Provides customized outer shapes and precise edges for improved assembly compatibility.

Applications

Sapphire through-hole bearings are widely used in:

• Optical instruments — gimbals, scanning assemblies, precision rotary modules

• High-precision measurement devices — dial indicators, micro-mechanisms

• Semiconductor and MEMS equipment — positioning and guiding components

• Medical devices — pumps, micro-rotors, analytical instruments

• Aerospace and defense — lightweight, stable micro-mechanical structures

• Luxury mechanical watches — extremely low friction & long service life

Typical Specifications (Customizable)

Advantages of Choosing Our Custom Sapphire Bearings

• In-house crystal machining and polishing

• 10+ years of sapphire component manufacturing

• Fast prototyping available

• Strict optical and dimensional inspection (interferometer, CMM, roughness meter)

• Stable mass-production capability

FAQ

Q1: Can you customize non-standard hole shapes (oval, stepped, tapered)?

Yes. We offer ultrasonic, CNC, and laser machining for special-shape through-holes.

Q2: What is the minimum hole size available?

We can achieve 0.2 mm micro-through-holes depending on thickness and aspect ratio.

Q3: Can sapphire bearings replace metal or ceramic bearings?

For low-friction, high-precision, and ultra-clean environments, sapphire bearings outperform metal and common ceramics.

Q4: Do you supply ruby through-hole bearings?

Yes. Ruby and blue sapphire materials are available in addition to colorless sapphire.