Choosing the bearing clearance, which should be considered from several aspects - bearing knowledge

Choosing the bearing clearance, should consider the following aspects: 1, the bearing of the working conditions, such as load, temperature, speed, etc. ; 2, on bearing operational performance requirements ( Rotating accuracy, friction torque, vibration and noise) ; 3, bearing and shaft and the shell hole for fit to the bearing clearance decreased; 4, bearings, the difference in temperature between inside and outside ring lead to bearing clearance decreased; 5, due to the shaft and the shell material expansion coefficient is different, lead to bearing clearance decrease or increase. 6, according to the experience of the use, the ball bearing is the most suitable work clearance is zero; Roller bearings with a small amount of work clearance shall be maintained. For bearing supporting rigid good parts, to allow a certain numerical pre-tightening force. Here in particular, the so-called work clearance, is refers to the bearing in the actual operation conditions of clearance. There is a clearance is called the original clearance, is refers to the clearance of the bearing before installation. The original clearance than installation clearance. Our choice of clearance, the main work is to choose the appropriate clearance. 7 valve inlet pump, the clearance value of national standard is divided into three groups: a basic group ( 0 group) , small clearance assisted group ( Group 1, 2) And the big clearance aided group ( Group 3, 4, 5) 。 When the choice, under normal working conditions, appropriate priority choose basic group, then can make the bearing work properly for clearance. When basic group cannot satisfy the use requirement, should choose auxiliary clearance. Big clearance auxiliary group applies to bearing and shaft and the shell hole USES the interference fit, the bearing inner and outer circle temperature difference is bigger, deep groove ball bearings under high axial load or need improve heart function, heart, and for higher limit speed and reduce the occasions such as bearing friction torque; Small clearance auxiliary set higher requirements applicable to the rotation of the precision, to strictly control the shell hole axial displacement, and the need to reduce vibration and noise. Clearance is normal work of the rolling bearing is one of the most important factors, divided into radial clearance and axial clearance. Select the appropriate clearance, can make the load between the rolling element bearing reasonable distribution; Can limit shaft ( Or shell) The axial and radial displacement, ensure the accuracy of the axis of rotation; Can make the bearing under the specified temperature normal work; To reduce vibration and noise, to improve the service life of bearing. So. When choosing bearing, it is necessary to select the appropriate bearing clearance.