How to choose the pump shaft even bearing the original radial clearance

Using rolling bearing internal clearance in great impact on the performance of bearing, including fatigue life, vibration, noise, temperature, etc. In theory, when there is a slight negative clearance, bearing service life may be prolonged. However, to obtain the ideal situation is so difficult, and too much of a negative clearance will greatly shorten the life of bearing. Often, therefore, should use zero clearance or slight clearance is not negative clearance. In choosing the pump shaft bearing radial clearance, the original in addition to consider due to the interference fit in the outer ring and bearing hole and the decrease of the amount of clearance, but also caused by temperature rise of components caused by the heat of the clearance decreases of water pump shell has two kinds of aluminum and iron shell. Even bearing shaft and shell with the interference fit, interference quantity recommended in table 1, because of the pump shaft bearing shaft and shell temperature difference is bigger, the minimum clearance requirements can be estimated out, but in most cases is achieved by the results of experiment and experience. RTL water pump shaft bearing in the absence of special requirements, complete sets of pump shaft radial clearance of the bearing is 15 35μm( No load clearance value) 。 Japan NSK company water pump shaft bearing radial clearance range of 10 - 40μm。 Germany FAG company water pump shaft bearing radial clearance range of 10 - 36μm。 The coat is bigger and recommend shell interference table ( Table 1. ) A: about water pump shaft under the service life of the bearing a: auto water pump bearing related basic dynamic load rating label: news bearing installation test and remove the judgment of the rolling bearings of the pump and check the auto water pump bearing which cases will fever auto water pump bearing thermal and bearing performance of engine cooling system of key parts of automotive water pump bearing related products