Mechanical bearings are a conventional and widely used technology, but fluid bearings are an excellent alternative and even superior in many respects. Though fluid bearings may be a new technology to some, they have been in use for a long time and are widely recognized for their unique operating characteristics. Below is more information on fluid bearings and a summary of several advantages they possess:
What is a fluid bearing?
Simply put, a fluid bearing is a specialized type of bearing with an axis of rotation on top of a layer of fluid. As opposed to mechanical bearings where solid surfaces touch one another to some degree, fluid bearings facilitate rotation without any contact at all between hard surfaces. Instead, fluid bearings are built with a separation between solid surfaces that is filled with a liquid or gas, depending on the desired application.
Fluid bearings are made in two broad configurations: hydrostatic and hydrodynamic. Hydrostatic bearings rest upon a layer of continually circulated fluid introduced by external pumps, where hydrodynamic bearings rely upon a static, sealed reservoir of fluid. The specific type of bearing chosen is dependent upon several factors, but one of the most important is whether or not continuous fluid replacement is readily available. For example, within the environment of a hard disk drive where precise, high speed rotation is essential, it is not practical to continuously recirculate fluids, and that makes hydrodynamic bearings the most reasonable option.
Advantages of fluid bearings
While fluid bearings are not ideal for every circumstance, such as when heavy loads are placed upon the bearing, they do have several advantages when compared to mechanical bearings:
Mechanical bearings generate rumbling and vibration due to the physical contact between surfaces inside the bearing. In the case of ball bearings, this vibration can only be reduced to a certain extent, and that is why fluid bearings are superior substitutes.
Minimal friction and heat
Fluids, particularly gases, maintain an extremely low level of friction between moving parts inside a fluid bearing. This allows for a minimal amount of interference between components and also results in a significant reduction of heat buildup. The reduction of waste heat protects the surrounding equipment and also can prevent process problems that may damage manufactured products.
Freedom from contamination
Hydrodynamic fluid bearings, especially gas bearings, possess an advantage over mechanical bearings by providing a natural barrier against contamination. Instead of using lubricants that may contaminate the ambient environment, the sealed nature of hydrodynamic bearings maintains the purity of processes where product integrity is of utmost importance. Certain gases, such as nitrogen or inert gases, provide a stable internal atmosphere that does not negatively affect or react with other objects, and this is also a key advantage of fluid bearings.
Cost and expense advantages
Fluid bearings can carry a substantial cost savings over certain types of mechanical bearings, particularly in the case of hydrodynamic bearings that do not require pumps or other equipment necessary for maintaining fluid circulation. Hydrodynamic bearings are relatively simple, robust equipment that can be manufactured more cheaply than many mechanical bearings, and this simplicity can carry over into operational considerations, as well. In addition, a properly installed and utilized fluid bearing can have a useful life that far outstrips mechanical bearings. This means replacement costs down the line are also considerably reduced.
Since fluid bearings do not utilize moving parts to maintain the rotation of components, the need to replace worn sleeves, bushings, balls and other components does not exist. This can eliminate much of the maintenance associated with ordinary mechanical bearings and lessen the need for interruptions of service. Fewer interruptions means more process up-time and production gains.
For more information, contact an air bearing system manufacturer.
After I started working in a factory for my grandfather, I realized that some of the equipment needed to be updated in a bad way. It was really old, and some portions were visibly breaking. I decided to make things right by finding better manufacturing equipment for him, so I started working on it right away. I was able to find an amazing deal on some new pieces to add to the workshop, and it really paid off. After about six months of using the new equipment, things were much better. This blog is all about the importance of using better equipment.