The total number of revolutions before contact fatigue wear of any element in a rolling bearing or the total working hours at a certain Load And Life speed is called bearing life. The life of rolling bearings varies greatly.
The life of bearings produced in the same batch can vary several times or even dozens of times Load And Life under the same conditions. When 90% of the total revolutions (or working hours) of the same batch of bearings can reach or exceed before fatigue spalling, it is called the rated life L.
The load that can be borne when the rated service life is 1 million revolutions is the rated dynamic load C. When the sum of the Load And Life plastic deformation at the contact between the rolling element with large load and the raceway reaches one ten thousandth of the diameter of the rolling element,
the load it can bear is the rated static load C0. The greater the Load And Life rated load, the stronger the load capacity of the bearing.
and the rated load of thrust bearing is pure axial load. The Load And Life actual load of the bearing is often different from the rated load and must be converted into equivalent load. Under the action of equivalent dynamic load P, the life of bearing is the same as that under actual load.
Under the action of equivalent static load P0, the total plastic deformation at the contact Load And Life between rolling element and raceway with large load is the same as that under actual load.
The relationship between the rated life, rated dynamic load and equivalent dynamic load of the bearing is in the formula ε Life index: ball bearing ε＝ 3. Roller Load And Life bearing ε＝ 10/3。 When selecting bearings, the expected life of bearings is usually taken as the period of medium repair or overhaul of the machine.
For example, the infrequently used equipment is 500 ~ 2000 hours; Machines that work 8 hours a day and use continuously for 20000 ~ 30000 hours; The machine used continuously for 24 hours a day is 40000 ~ 100000 hours. In fact, Load And Life only a few bearings are damaged when the expected life is reached.
The outer spherical bearing fixes the bearing inner ring and the Load And Life shaft through the eccentric sleeve, and the hexagon socket screw on the eccentric sleeve plays a fastening role.
During maintenance, many operators cannot disassemble this bearing, so it is necessary to introduce the technical points and precautions for disassembling and assembling the outer spherical bearing:
1. First loosen the locking screw on the bearing eccentric sleeve with an Allen wrench, then insert a small iron rod into the counterbore on the top cover eccentric sleeve, and loosen the eccentric sleeve against the rotation direction of the shaft.
2. Loosen the bolts fixing the bearing seat. Remove the bearing together with the bearing seat from the shaft. Before removing the bearing seat at one end of the shaft, loosen the bolts of the bearing seat at the other end of the shaft to avoid damage to the bearings at both ends.
1. Before installing the bearing on the shaft, the fixing pin of the bearing sleeve must be pulled out, the surface of the journal must be polished smooth and clean, and the journal shall be coated with oil for rust prevention and lubrication (the bearing is allowed to rotate slightly on the shaft).
2. Apply lubricating oil on the mating surface of bearing seat and bearing, and install the bearing into the bearing seat. Then sleeve the assembled bearing and bearing seat on the shaft. Push it to the required position for installation.
3. Do not tighten the bolts fixing the bearing seat first, and make the bearing sleeve rotate in the bearing seat. Similarly, install the bearing and seat at the other end of the same shaft, rotate the shaft for several turns, and let the bearing itself automatically align. Then fasten the bearing seat bolts.
4. Install eccentric sleeve. First put the eccentric sleeve on the eccentric step of the bearing inner sleeve and tighten it by hand along the rotation direction of the shaft. Then insert or counter the small iron rod into the counterbore on the eccentric sleeve.
Knock the small iron rod along the rotation direction of the shaft with a hand hammer to firmly install the eccentric sleeve, and then lock the Allen screw on the eccentric sleeve.