The service life of integral eccentric bearing begins with the correct bearing selection. From the beginning, bearing designers extended bearing life and equipment performance by selecting the right bearings for different applications. Many factors should be considered in this process, such as load, hardness, bearing life prediction, operating environment and so on.
In principle, all integral eccentric bearings should be kept in their original packaging before installation. They need to be kept in a clean, moisture-free, relatively constant temperature environment. Rolling bearings should be kept away from dust, water and corrosive chemicals. Shaking and vibration may permanently damage the mechanical properties of the bearing, so vibration must be avoided during handling and storage.
Basically, all bearings must be stored horizontally, because some heavier bearings may be deformed due to their own weight after being placed vertically for a long time.
Pre greased (or sealed) integral eccentric bearings require special care because the density of the grease will change after long-term storage. In this way, when the bearing is used for the first time, there will be a certain degree of rotation noise. Therefore, the shelving time of this bearing should be controlled according to the principle of first in first out.
(1) In gas turbines and some machine tools and engineering machinery, high speed and large axial load, the service life of ball bearings is too short, the axial load capacity of short cylindrical roller bearings is insufficient, and the axial clearance is difficult to adjust. We hope to use the integral eccentric bearing to break through this problem.
(2) The technical key that must be solved is to improve the lubrication state between the large retaining edge of the inner ring and the large end face of the roller. This part is most prone to severe wear and burn at high speed, which is the main reason to limit its high speed.
(3) Solution in the integral eccentric bearing with ordinary structure, the flow route of lubricating oil is in the contact part between the large retaining edge of the inner ring and the large end face of the roller. It is difficult to get lubricating oil, and this part is relatively large in sliding, which is exactly the most in need of lubricating oil. Therefore, Japan and other countries have developed HA type integral eccentric bearing. The bearing retaining edge is in the outer ring, so that the circulating lubricating oil can lubricate the contact part between the outer ring retaining edge and the large end face of the roller. At the same time, some oil can be stored here even when it is still, so as to avoid the accident of poor oil burn during starting. However, several oil drain holes are set on the outer ring retaining edge as needed to avoid no oil discharge channel, * the oil loss and temperature rise are caused by oil retention. Because the inner ring has no retaining edge, the temperature is reduced, which reduces the possibility of creep between the mating surface between the inner ring and the shaft. The bearing of this structure adopts the outer ring guiding mode for the cage, so that the cage can guide the roller smoothly and operate normally without skewing, so as to avoid vibration and excessive wear, which is also conducive to high speed.
4) The DMN value of this ha type bearing can reach 2 million, which is twice higher than that of the ordinary structure. For example, this bearing (model i-ia30205) used for the main shaft of gas turbine reducer can ensure an oil supply of 2l / min under the condition of axial load of 1000N. The bearing is circularly supplied with No. 4 turbine oil, and its working speed can reach 60000, so as not to cause burns