How to measure rolling bearing clearance
March 17, 2014 8:22pm CST
So-called rolling bearing clearance, is a fixed ring, a ring along the radial or axial maximum activity. Along the radial direction of the maximum activity called radial clearance, the largest activity along the axial axial clearance. In general, the larger the radial clearance, axial clearance is bigger, and vice versa. According to the bearing of the state, the clearance can be divided into the following three: First, the original clearance Before installation free state of clearance of the TIMKEN Roller Bearings . The original clearance is processing, assembling the identified by the manufacturer. Second, the installation clearance Is also called cooperate clearance, bearing and shaft and bearing seat installed but not yet work clearance. Due to the interference installation, or make inner ring increases, or the outer shrink, or both, make installation clearance is smaller than the original clearance. Third, work clearance Bearing in the working state of clearance, the largest circle temperature rise at work, is the largest thermal expansion, reduce bearing clearance; At the same time, as a result of the action of load, rolling element and raceway contact produce elastic deformation, the bearing clearance increases. Bearing clearance than installation clearance big or small, depends on a combination of these two factors. Some rolling bearings can not be adjusted clearance, more can't remove, these bearings have six models, namely 0000 type 5000 type; Some rolling bearings can adjust the clearance, but cannot remove, type 6000 (angular contact bearings) and inner ring cone hole type 1000, type 2000 and type 2000 rolling bearing, these types of rolling bearing installation clearance, after adjustment will be smaller than the original clearance; In addition, some of the bearing can be removed, more can adjust the clearance, type 7000 (tapered roller bearing), type 8000 (thrust ball bearing) and 9000 (thrust roller bearings) three, the three bearing does not exist the original clearance; Type 6000 and type 6000 rolling bearing, the radial clearance is small, the axial clearance is smaller, and vice versa, and type 8000 and type 8000 rolling bearing, it is of practical significance for the axial clearance only. The installation of the appropriate clearance can help the normal work of the rolling bearing. Clearance is too small, rolling bearing temperature, cannot work normally, and roller jammed; Clearance is too large, large equipment vibration and noise of rolling bearings. Radial clearance inspection method is as follows: A, feel 1, have hands rotating bearing, bearing should be smooth and flexible no jamming phenomenon. 2, rock bearing outer ring with the hand, even if the radial clearance is only 0.01 mm, axial travelmotion of the top bearing point, there are 0.10 ~ 0.15 mm. This approach dedicated to the single-row radial ball bearings. Second, the method of measurement 1, with a feeler check, confirm the maximum load position rolling bearing, with 180 ° between the roller and outside (inside) circles into feeler, elastic fitting for feeler thickness is the radial clearance of the bearing. This method is widely used in self-aligning bearings and cylindrical roller bearings. , 2, with a dial gauge to check the dial indicator to zero, then the top roller bearing outer ring, the reading of the dial gauge is bearing radial clearance. The axial clearance inspection method is as follows: 1, feeling Check the axial clearance of rolling bearings with finger, this method is applied to the shaft end exposed. When the shaft end sealing or for other reasons and can't check with your fingers, can check flexible rotation axis. 2, measuring method (1) using feeler check, operation method and check out the radial clearance with a feeler is the same, but the axial clearance should be C = lambda/sin (2 beta) Type of c - axial clearance, mm; The thickness of the lambda - feeler, mm; Beta - bearing cone Angle, (°). (2), were examined with a dial indicator with crowbar channeling shaft axis in two extreme position, the difference of the dial gauge readings for bearing axial clearance. But on the levers are not too large, otherwise shell elastic deformation occurs, even if the deformation is small, also affect the accuracy of the measured axial clearance.