Silicon nitride bearings (Si3N4) for shaft sizes from 0.125 inches up to 1.0 inches
Si3N4, or silicon nitride bearings, are designed to offer excellent performance in a variety of demanding applications. Si3N4 is a ceramic material that provides strength and durability, even in high-temperature environments. These bearings are significantly lighter than their steel counterparts, which allows for reduced centrifugal forces. In addition, they exhibit superior corrosion resistance, making them ideal for use in harsh environments such as chemical processing, marine applications and vacuum applications.
One of the key advantages of silicon nitride bearings is their low density, which reduces the overall weight of the bearing. This characteristic, combined with high hardness and excellent wear resistance, ensures a long service life and reliable performance.
The ceramic balls used in these bearings are also electrically insulating, which prevents electrical arcing and damage in electrical applications.
Full complement bearings
Full complement bearings are specially designed to accommodate heavy loads. Unlike traditional bearings that use a cage to separate the rolling elements, full complement bearings contain the maximum number of balls or rollers, allowing them to handle higher loads. This design is particularly useful in applications where maximum load capacity is required and can be used up to 1200°C. The absence of a cage also significantly reduces the maximum speed so full complement bearings are best suited to low speed applications in aggressive environments.
Bearings with a PEEK cage are rated up to only 250°C. Silicon nitride bearings with a 316 stainless steel cage can be used up to 500°C.
Although silicon nitride expands much less than ZrO2, it is still advisable to specify greater internal clearance at very
For temperatures below -70°C it is worth considering PTFE or 316 stainless steel cages due to their better low temperature performance. For an overview of the pros and cons of silicon nitride bearings, you can view our ceramic bearing selection guide.
Non magnetic bearings
Si3N4 bearings are not magnetic, and they are highly corrosion resistant to most chemicals. They are also electrically insulating. Like ZrO2 bearings, they are also water resistant which is why they are often used in marine applications. They can be fully and permanently submerged without the material being affected.
Due to their greater brittleness, Si3N4 bearings have slightly lower load ratings than ZrO2 bearings but will still support much higher loads and speeds than 316 marine grade bearings.
In applications where magnetic interference must be avoided, non-magnetic bearings are the solution. These bearings are essential in sensitive equipment such as medical imaging devices, e.g., MRI machines and high-vacuum environments. Our non-magnetic bearings are made from materials like silicon nitride and zirconia to ensure they do not affect, and are not affected by, magnetic fields.
Non-magnetic bearings provide the same high performance and durability as our other specialized bearings. They are resistant to corrosion and can operate effectively in extreme temperatures. These features make them suitable for use in various industries, including aerospace, medical, and scientific research.
Key features and benefits
Stainless steel bearings
In addition to our silicon nitride bearings, we offer stainless steel bearings that provide excellent corrosion resistance and durability. Stainless steel bearings are perfect for applications that involve exposure to moisture, some chemicals and other mildly corrosive substances. The combination of stainless steel with silicon nitride balls enhances the performance, offering both the strength of metal and the advanced properties of ceramic materials.
Silicon nitride ball bearing
Our silicon nitride ball bearings are designed to provide superior performance in highly aggressive environments. These bearings also exhibit excellent wear resistance with no lubrication and can operate in extreme temperatures, making them suitable for cryogenic or high-temperature applications.
Advantages of full complement bearings
Full complement bearings offer several advantages over traditional bearings, including:
- Increased load capacity: The absence of a cage allows for more rolling elements, which increases the load capacity
- Higher operating temperatures: Without a cage, full complement bearings can be used within the very wide temperature range of silicon nitride rather than the cage material.
- Space efficiency: Full complement bearings are ideal for applications where space is limited, as they provide a greater load capacity in a more compact design.
Our range of bearings, including silicon nitride bearings, full complement bearings and non-magnetic bearings, is designed to meet the diverse needs of different industries. Whether you require bearings that can handle high loads, operate in high temperatures, or avoid magnetic interference, we have the right solution for you.
Most of the range of Si3N4 ceramic bearings are supplied from stock in the UK. We also keep ZrO2 full ceramic bearings in stock. See products variants below for the ZrO2 versions and flanged options.
See product table below for dimensions and technical drawings
Click on INFO in the rows below to display technical drawings of the bearings with load and speed data. Please note that the maximum loads and speeds are used in theoretical life calculations. It is recommended to use bearings at significantly less than the maximum load and speed ratings to ensure reasonable bearing life. Si3N4 full ceramic bearings are best used with low to medium speeds and loads due to their greater brittleness.
Get in touch with our specialist bearing team today by emailing sales@smbbearings.com or fill in the contact form.
