What problems should be paid attention to when using spherical roller bearings
The pre-tightening force of spherical roller NSK bearings is carried out at room temperature, but in working condition, the drive shaft and bearing pre-tightening force generated by the system's micro-stretching temperature rise will change. Therefore, the set pre-tightening force should be considered To this factor.
It needs the capacity, speed, and other conditions of the reasonable use of the preload of the spherical roller bearing to ensure the life of the transmission. If the pre-tightening force is too large, the power consumption will increase, which will cause overheating. If the preload is too small, the body load, shaft rolling, and the gap between the outer ring will produce beating, running, and transmission accuracy to reduce the increase in noise, which affects the gear meshing and severely damages the teeth and bearings.
According to different spherical roller bearing assembly, such as: the bearing pre-tightening nut which directly compresses the inner ring of the inner bearing axially rotates the inner and outer rings to eliminate the gap and achieve the purpose of bearing pre-tightening force
1. Electric heating plate heating method. Put the bearing on the electric heating plate at a temperature of 100℃ for a few minutes. This method is relatively simple. For example, the bearing can be heated evenly by turning several times, and the efficiency is also high. Both large and small spherical roller bearings This method can be used.
2. Electric furnace heating method Put the bearing in a closed automatic temperature control electric furnace for heating, uniform heating, accurate temperature control, fast heating, and suitable for heating many bearings in a batch.
3. The induction heating method uses induction heaters to quickly, reliably and cleanly heat the spherical roller bearing to the required temperature. This is especially suitable for the occasions where the inner ring is tightly fitted, because only the inner ring is heated, and the outer ring is heated. The ring is less heated, so it can be easily installed on the shaft and easily installed in the seat hole.
4. The electric bulb heating method uses a 50W electric bulb to heat the spherical roller bearing, which can ensure that the heating temperature is about 100°C. The smaller bearing can be placed directly on the bulb, and the larger bearing can be placed in the conical cover of the bulb. The cover can prevent the heat loss of the bulb, and make the heating uniform. The cone cover can be adjusted up and down. It can be adapted to heating bearings of different sizes within a certain range. If a far-infrared bulb is used, pay attention to the direction of the bulb downward to avoid infrared rays that are harmful to people. This kind of light bulb can be energy-saving bulb heating method is suitable for a small number and not often needed; occasions where the bearing needs to be heated, the bulb can also be used for lighting at ordinary times, and no other equipment is required.
5.Oil groove heating method This is a widely used traditional heating method. The oil groove is 50~70mm away from the bottom of the metal mesh. The bearing is placed on the net. The large bearing should be lifted with a hook. The bearing should not be placed directly at the bottom of the groove to prevent contact with the groove. The bearing part at the bottom is locally heated too high, or the dirt deposited at the bottom of the groove enters the bearing oil groove. The points of attention of the heating method are as follows: non-corrosive mineral oil with good thermal stability should be used, which can be transformer oil, and the oil and container should be kept. The capacity of the clean oil tank should be determined by the size of the heated spherical roller bearing and the amount of oil.If the container is too small, the temperature of the oil will drop quickly when the bearing is put into the bearing during continuous operation, and the effect will not be good.