The thrust ball bearing is designed to bear thrust load at high speed, which is composed of washer ring with ball rolling raceway groove. Because the ring is cushion shaped, the thrust ball bearing can be divided into two types: flat bottom cushion type and self-aligning spherical cushion type. In addition, the bearing can bear axial load, but not radial load.
form
Thrust ball bearing composition: thrust ball bearing is composed of race, shaft ring and steel ball cage assembly. The shaft ring matched with the shaft and the seat ring matched with the shell
Type:
According to the force situation, it is divided into one-way thrust ball bearing and two-way thrust ball bearing. One way thrust ball bearing can bear one-way axial load. Two way thrust ball bearing can bear two-way axial load, in which the shaft ring is matched with the shaft. The bearing whose mounting surface of race is spherical has self-aligning performance, which can reduce the influence of mounting error. The thrust ball bearing can't bear the radial load and the limit speed is low.
characteristic
1. One way, two-way two types are available. 2. In order to allow installation error, either one-way or two-way, you can choose spherical self-aligning spherical cushion type or seat ring type with spherical surface. 3. High quality steel - ultra clean steel which can prolong the bearing life by up to 80%. 4. High grease technology - NSK lubricant technology can prolong the grease life and improve the bearing performance. 5. High grade steel ball - quiet and smooth when rotating at high speed. 6. Installation error can be allowed by using the ring in the option
purpose
Application of thrust ball bearing: it is only applicable to the parts bearing one side axial load and low speed, such as crane hook, vertical water pump, vertical centrifuge, Jack, low speed reducer, etc. The shaft ring, seat ring and rolling element of the bearing are separated and can be assembled and disassembled separately.
assembling
There are two key points in the assembly of thrust ball bearing. One is the quality control of cage and steel ball pressing, the other is the control of nominal height t after bearing assembly. In addition, because the shaft ring and seat ring can be separated, it brings a management problem, which is to prevent imported bearing parts from being mixed. After pressing, the steel ball is required to rotate flexibly in the pocket, but it can not fall off from the pocket, and the displacement of the steel ball in the pocket shall be checked according to the technical regulations. If the solid cage is pressed too deeply, the ball movement will be small, and the connection between the embossed convex part and the cage is too little and the strength is insufficient, which is easy to cause the cage to be scrapped. In order to prevent the phenomenon of mixed sleeve, it is found that both of them are seat rings or shaft rings. It is necessary to take certain measures. Usually, the pulling ring and the seat ball are distinguished with the aid of auxiliary tooling, or the inner diameter size is checked with the inner diameter plug gauge before the nominal height is checked. In order to check the inner diameter conveniently, the seat ring is placed below and the shaft ring is placed above. If the inner diameter of the seat ring has obvious quenching heating oxidation color or does not go through grinding, it is not necessary to check the inner diameter size. The difference between the shaft ring and the seat ring can be clearly seen, and it is not easy to mix. After the assembly of thrust ball bearing, the nominal height t should be measured to confirm whether it is qualified. During the measurement, the height block or standard part is used for calibration, and the load is measured. The bearing needs to rotate dozens of times, and the minimum height must be reached.
When the thrust ball bearing operates at high speed, the contact angle between the ball and raceway will be affected by centrifugal force, which will cause the ball to slide relative to raceway. The adhesive wear caused by this sliding will damage the bearing. In order to prevent this kind of damage, the minimum load on the thrust ball bearing must be ensured. See Formula 1 or formula 2, and the larger one is taken.
Formula 1: famin = k · n * n
Formula 2: famin = COA / 1000
Famin: minimum axial load (n)
K: Minimum axial load factor
n: Speed (per minute)
CoA: basic static load rating (n)
The one-way thrust ball bearing can only bear the load in one direction. If it bears the load in two directions, the two-way thrust ball bearing must be selected. The minimum load or preload must be applied to the thrust ball bearing. When the shaft is vertical, the weight of the shaft usually exceeds the minimum load. At this time, due to the influence of the axial external load in the opposite direction, the load may be reduced.