The demand for bearings to be used in extreme environments has been on the rise due to technological advancements.
For example, equipment used in outer space for solar panels and semiconductors requires that bearings, and bearing components, have special lubrication and be ultra-clean with no trace of surface solvents, which could result in outgassing when exposed to harsh environments.
Furthermore, these types of bearings can see working temperatures exceed 500° C (932° F) which causes conventional grease or oil lubrication to evaporate when the bearing is in use.
GMN precision bearings are the ideal solution for harsh environment applications due to our enhanced reliability, efficiency, and speeds. Contact our team of in-house engineers to find the best precision bearing for your harsh environment application.
Types of Harsh Environments & Equipment
When selecting high-precision bearings for harsh environments, it is essential to consider factors such as temperature range, load capacity, speed requirements, sealing effectiveness, lubrication requirements, and the presence of corrosive substances.
GMN bearings are the trusted solution for a variety of harsh environment applications, such as:
High-Vacuum Environments:
Electron-Scan Microscopes use precision bearings to support sensitive components like the specimen stage and beam deflection system, ensuring smooth, low-vibration motion and accurate positioning for high-quality imaging. Turbo-Molecular Pumps use high-speed turbines often supported by ceramic or hybrid bearings that run without lubricants, reducing friction, wear, and particle buildup even at tens of thousands of RPM.
Aerospace:
In airplanes, precision bearings are used in several key subsystems. In jet engines and turbines, they’re crucial for supporting high rotational speeds and temperatures. In landing gear and flight control systems, their ability to withstand heavy loads during landing or takeoff and enable precise motion in actuators and flaps proves reliable performance; because when it comes to safety, there’s no room for error. Likewise in spacecraft, satellites, and space station(s), precision bearings in reaction wheels, camera mounts, and antenna drives keep things in motion for accurate alignment of important systems in such extreme environments.
Semiconductors:
Furnaces used in chip manufacturing are used to heat silicon wafers in a controlled way under extreme temperatures. Precision bearings play a key role here, keeping wafer handling, rotation, and alignment smooth and accurate. Bearings made from stainless steel or hybrid materials like silicon nitride are designed to resist corrosion and minimize contamination, ideal for operations in cleanroom environments.
Medical Equipment:
In X-ray tubes and similar diagnostic imaging equipment, precision bearings help cut down on vibration and noise, keeping rotation smooth and ensuring clear and accurate images. Their specially designed cages spread loads evenly and reduce friction so that the equipment can run efficiently and reliably, even during long periods of use.
Suggested Bearing Design Examples for Harsh Environment Applications
The following are examples of bearing component options that GMN manufactures for harsh environments:
- Rings and balls: High temperature tool steel
- Ceramic balls made from silicon nitride (Si3N4)
- Cage material: heat resistant steel
- Rings, balls and cage made from heat resistant steel
- Rings completely gold plated (Au, PVD sputtered)
- Dry Lubrication
- Back-to-back preloaded spindle bearing pair
- Rings and balls made from SAE 52100 (100Cr6)
- Special Vacuum oil lubrication
Special applications might require the use of emergency bearings, also known as touchdown bearings, or backup bearings. These applications can utilize any of the above component options, and/or:
- Full ball complement (no bearing retainer/cage)
- Solid lubrication: Rings MoS2-coated; Balls MOVIC® treated
Cleaning & Coating Bearings for Harsh Environments
Ensuring there are quality standards and processes in place for harsh environment bearings is extremely important. At GMN, we divide our quality protocols into two main categories: Cleaning and Coating, each with dedicated quality standards.
Plasma Cleaning for Special Bearings
Each bearing component must have a reactive, clean metal surface for the coating to adhere properly. We achieve this using our plasma cleaning equipment.
Plasma cleaning is the process of removing all organic matter from the surface of bearing components using an ionized gas, also called plasma. This cleaning process uses no harsh chemicals thus will not leave any dry residue or solvents on the surface of the bearing.
Once completed, we vacuum dry each bearing component. Our plasma cleaning process enhances coating adherence to our bearing components.
Physical Vapor Deposition (PVD) Coating for Special Bearings
PVD is the process of applying thin deposits of vaporized metal film onto pure metal or alloy. This coating will lubricate the bearing components without burning off or outgassing.
A PVD coating performs as a lubricant for bearing components that operate in extreme environments. Our magnetron machine sputters out a PVD solid lubricant to coat the bearings.
Bearings with a PVD coating have superior hardness, durability and resistance to wear. These coatings also reduce friction on moving parts which is crucial to vacuum environments.
Depending on the bearing application, the PVD sputtering process can serve as protection against:
- Cold welding
- Damaging heat
- Lubrication degassing
All of which could rapidly decrease the lifespan of a bearing.
PVD Coating Equipment
At the GMN manufacturing facility in Germany, we have state-of-the-art Magnetron PVD equipment with sputter technology. Simply put, our PVD equipment can run anything that needs to vaporize a solid material and deposit it onto another.
Our PVD equipment is optimized for high precision bearing components and is custom designed for coating complex 3D surfaces without mechanical interference.
PVD Equipment Features
- Coats a wide variety of component materials like metals, semiconductors and ceramics, no matter what the melting point or vapor pressure may be for that material.
- Applying layers of coating won’t impact the maximum working temperatures of the components.
- Each PVD layer is equally distributed. Our plasma cleaning process ensures that a strong bond will occur between the PVD coating and the bearing component.
- PVD layer thickness can vary from a few nanometers (10-9 nm) up to microns (10-6 μ). The -9 and -6 need to be superscript, they are to the power of the 10
- PVD coatings produce the least amount of chemical waste.
Selections of PVD Vaporized Metals (for Coating)
- Silver (Ag),
- Gold (Au)
- Molybdenum disulphide (MoS2)
- Lead (Pb) - special certifications are required to ship into the USA.
Bearing Component Metal Selections
- Chrome steel (AISI 52100)
- Copper
- Titanium
Please note: All bearing components, rings, balls and cages, are manufactured from heat resistant high-speed tool steel or alloys. As an alternative, we offer hybrid bearings with ceramic balls made from silicon nitride (Si3N4).
Shipping & Installation for Special Harsh Environment Bearings
The bearings receive special treatment, packaging and transportation per the requirements of each order and application. We’re happy to accommodate any special shipping conditions you may have.
We can also store the bearings in a nitrogen-filled box if needed.
We need to ensure that the coating of the bearing can’t get damaged during handling and assembly. Our GMN engineers will help you determine the correct handling procedures, and they can help you find the special harsh environment bearing that’ll meet your needs.
Contact us today to talk to our onsite bearing engineers.