The answer to this month’s trouble shooter is provided by SKF. Q: Why would I need a magnetic bearing?
Published: 13 August, 2015
Magnetic bearings are a non-contacting technology, which means that they offer a range of important benefits, from almost zero friction and vibration, through reduced energy consumption and bearing wear, to higher reliability and longer operating lives than their conventional counterparts. In addition, previously unachievable surface speeds of up to 100,000 rpm can now be realised, while the need for lubrication and maintenance is also eliminated, meaning that magnetic bearings are ideal for use in processes that are sensitive to contamination, or where environmental impact and the rising cost of energy are top priorities.
Although recent developments in magnetic bearing technologies and computer power have led to a reduction in the size of control systems and an increase in performance, magnetic bearings do not offer a perfect drop-in solution for every application. They are more complex than that, but for the right application, they are the ideal choice. In addition, to take full advantage of the benefits on offer, it is important to combine magnetic bearings with other devices, such as a high-speed brushless DC motor or permanent magnet motor.
Where magnetic bearing systems are used the addition of monitoring equipment means that they can be actively assessed to reduce maintenance costs and downtime. This approach offers real time snapshots of key operating parameters, including positions, currents and forces, giving warning of anomalies, while allowing alarm logs to capture all system variables on either side of an unusual event, as well as recording irregularities for short and long term trending activities. Active monitoring systems help not only to improve machine reliability, but also enable better decisions to be made based on what is known about a specific process.