Lab Created Sapphire Bearings Spherical Through-Hole Gem Bearings
Sapphire precision parts are generally used in the wear-resistant
and high-temperature parts of instruments, meters, and equipment.
Sapphire has a hardness of 9 on the Mohs level, second only to
diamond, and has good wear resistance. At the same time, it has
excellent chemical stability and can resist almost any acid and
alkali corrosion. In addition, the maximum temperature of sapphire
reaches 2060℃. It is precisely because of the above advantages of
sapphire that sapphire is used in instrumentation equipment, which
can significantly increase the service life and withstand various
harsh environments.
Gem bearings are sliding bearings made of hard materials such as
gemstones. A natural or synthetic gem (usually a sapphire) that,
after careful grinding, is carefully ground out in a conical hole
and can be used as a bearing for the head-turning shaft or for
other precision instruments.
Gem bearings are mainly used in instrumentation. Instrument
bearings bear a small load, but to rotate high accuracy, good
sensitivity, long service life. Gemstones have small friction, high
hardness, corrosion resistance, low coefficient of thermal
expansion, high performance of pressure strength, to meet the
requirements of the use of instrument bearings. The materials for
making gem shafts include corundum, agate, microcrystalline glass,
etc. Corundum is the body of alumina, natural and man-made. Natural
corundum impurities are more, uneven texture, so artificial
corundum is the most widely used.
Product specifications:
1. Outer circle diameter D:0.06-20.00mm, outer circle tolerance up
to 0.005mm.
2. Thickness H:0.20-8.00mm, thickness tolerance of up to 0.01mm,
two-sided parallelity error is not greater than 0.02mm, surface
roughness up to Rz0.1 (mirror), the verticality error of both ends
relative to the inner hole axis is not greater than 1 degree.
3. Inner hole diameter d:0.13-3.00mm, aperture tolerance can be
controlled at a minimum of 0.004mm, inner hole roundness tolerance
and cylindrical tolerance is not large bearing inner hole
tolerance.
4. Oil tank: depth h - 1/3H, tolerance minimum can be controlled at
0.04mm, curvature radius SR minimum can be controlled at 0.30,
surface roughness up to Rz0.2 .
| General | Chemical Formula | Al2O3 |
| Cystal System | Hexagonal system |
| Melting Temperature | 2040℃ |
| Thermal | Thermal Expansion | Parallel to C-axis:6.7*10-6 |
| Perpendicular to C-axis:5.0*10-6 |
| Specific Heat | 0.18 Cal/gm°K(25℃) |
| Mechanical | Density | 3.98-4.1g/cm3 |
| Hardness | 9 Moh's Scale |
| (Hv)≥1700kg/mm2 |
| Modulus of Elasticity | 340-380Gpa |
| Compressive Strength | 2.1Gpa |
| Tensile Strength | 0.19Gpa |
| Optical | Index of Refraction | Parallel to C-axis:1.769 |
| Perpendicular to C-axis:1.769 |
| Index of IR Transmission | 85% |
| Electrical | Electrical Resistance | ＞1016Ω/cm(25℃) |
| Dielectric Constant | 7.5-10 |
| Chemical | Erosion Resistance | Can not be corroded by adid or alkali at mormal temperature, only
can be corroded by HF at 300℃ |
FQA
1. Are you a trading company or factory?
We are a professional factory of sapphire products, also a trading
company .
2.Can you do customized products?
Yes, we specialized in customized production or OEM work.
CAD,3D drawing are needed.
3.Could you provide samples?
Yes, we could provide samples with a charge, but if you place the
order with a quality above 100pcs, the sample charge will be
refunded.
4.What’s the delivery time?
It depends on the type of products and the quality.
For watch case, the regular time is around 5-8 weeks for 200pcs
according to the difficulty of the processing.
5.How about the payment?
T/T payment is prefered.
6.How about the delivery?
Mostly by air, like DHL, Fedex.
