A mechanical bearing is simply referred to as a device […]
A mechanical bearing is simply referred to as a device to allow the two portions constraints, typically the rotational or linear relative motion between the motion. Today, for the spindle bearings it has undergone various incremental improvements. Compared with steel bearings, ceramic hybrid ball bearings ball more popular. But now, in addition to traditional bearings, manufacturers still choose other options on high-speed milling spindle. Their choice of milling spindle bearings are mainly used to make fundamental changes. One such option is to use a fluid hydrostatic bearing or ball bearing instead of mechanical bearings that there is no contact between the moving surface.
Fluid bearings can not be classified as absolutely new idea, because the practice of using water as a bearing medium is relatively primitive. The only new aspect is the higher demand for the application of this technology in the milling spindle. Today, a fluid bearing is defined as a non-contact bearing, wherein there is no contact between the moving surfaces. Today, the spindle motor can now provide more power, but now available cutting tools can increase the use of power. The only constraint here is the bearing. Using mechanical bearings can be long-term use. On the other hand, milling spindle used in hybrid ball bearings seems to represent practical limits how much power and speed using mechanical bearings.
Advantage is that the fluid bearing can be used in high-power high-speed machining.
Fluid also helps deliver smooth motion, and to ensure a smooth and even beating low vibration. These types of bearings are mainly used hard steel mold and die milling aerospace industry.
Many advantages fluid bearing. The fluid bearing fluid spinning assembly stationary assembly completely isolated. Even air will produce effective non-contact bearing. Compared with other bearings, noting the need for expensive magnetic bearing spindle design, and the lack of air bearing stiffness. Use as a bearing fluid medium, can be produced cost-effective heavy-duty cutting spindle. In addition, the fluid bearing can bear a greater load. Beating the spindle is low due to lack of contacts. Fluid bearings do not require much maintenance, and therefore does not provide opportunities for mechanical contact with the moving parts to wear, and therefore a longer service life of the frame.
However, this mechanical bearings also has some drawbacks. Using a fluid bearing leads to poor efficiency related to the viscosity of the liquid, causing the fluid friction. In order to overcome this resistance and resistance to viscosity loss bearing spindle motor must work harder. Although low speed hydrostatic bearing can be used as the oil viscous liquid, but higher rpm liquids require more liquid, but water is not a simple alternative. Nonreactive oil is a good choice, but that too can not be used with water. To bearing medium water is used, the spindle must consider the various other steps in the manufacturing process, such as coating the internal components, with deionized water and sealed motor.