The so-called bearing clearance, which means bearing when it is not installed in the shaft or bearing box, circle or outer ring fixed therein, and the party has not been fixed amount of movement when doing radial or axial movement. According to the direction of movement can be divided into radial clearance and axial clearance.
Running clearance (clearance) size on the fatigue life of rolling bearings, temperature rise, noise, vibration can affect the performance.
When measuring the FAG bearing clearance, to get a stable measuring value, generally imposed under the measuring load on the bearings.
Therefore, the measured values than they got real clearance (referred to as the theory of clearance), an increase of measuring elastic deformation of the load.
For the roller bearings, however, due to the elastic deformation smaller, negligible.
FAG bearings internal clearance before installation with the theoretical clearance.
Complete set of radial internal clearance of the bearing measurement will not be easy, measuring the rings and rolling itself and its contact elastic deformation, deformation is the cause of error factors, its contact with the measuring force, and rolling elements related to the location of the State. Bearing rotation flexibility in horizontal position checked, usually to fix the inner ring (or handheld) by hand, rotate the outer ring, check for abnormal noise bearing rotates and blocking. Generally speaking, bearing long to rotate, stop slow, flexibility is good. In contrast, rotation time is short, stop suddenly, flexibility is not good. Because of different bearing type and size, rotate it flexibility should also have different requirements. Like separate centripetal ball bearing, and separate centripetal thrust ball bearing, due to scroll body and rings Zhijian of contact area small, these FAG bearing rotating Shi on comparison brisk, and double column centripetal spherical bearing and thrust roll child bearing, due to scroll body and roll road of contact area larger, patrons ring of weight and smaller, in check its rotating flexibility Shi, although plus must load, but its brisk degree still than separate centripetal ball bearing. For large bearings, when you rotate it should be is not stuck, and no check for General rotation sound. For bearings with a tapered bore, add the following methods to check the bearing rotation flexibility available, do the following: press the taper bore into mandrel until the radial preload a certain, in this pre-load, when a ring turning scroll body should be turned. If rolling slide instead of turning, then the ring geometry defects excessive or uneven rolling, rotation of the bearing less flexibility.
Measuring radial clearance of bearings FAG considerations
(1) as far as possible the use of special instruments and measurement.
(2) measurement using the push method calls for high measurement by measuring skills. This method of measurement error is large, especially when clearance marginalized, prone to error, in which case the instruments shall prevail.
(3) feeler gauge to measure, as stipulated in the standard operation, rolling over the roller feeler gauges shall be used methods of measurement.
(4) in the measurement process, shall ensure the ball falling into the ditch; closed type bearings in front of the closed measurements; load devices, measuring value by subtracting the load caused by increase in the clearance.
(5) for multiple-row bearings, each clearance pass take the arithmetic mean of the clearance as the radial internal clearance of the bearing.
Product Model | Inside Diameter | Outside Diameter | Thickness |
7004CDB NSK | 20 | 42 | 12 |
7004ADB NSK | 20 | 42 | 12 |