Jaw crusher bearings are important parts of jaw crushers, generally socket roller bearings are used.
1. Introduction
The bearing is an important part of the jaw crusher. Generally, rocket roller bearings are used. The specific model of the bearing can be determined from the three aspects of bearing size, bearing accuracy and bearing internal clearance.
A Bearing size
The size of the eccentric shaft is calculated from the crushing force. After the journals of the eccentric shaft at the frame bearing and the movable jaw bearing are initially determined, the bearing specifications are initially determined based on this, and the medium-width series specifications are usually selected as much as possible to check the theoretical service life of the bearing To meet relevant standards.
B Bearing Accuracy
Bearing accuracy includes two aspects: dimensional tolerance and rotation accuracy, whether it is the geometric tolerance of each component of the bearing or the radial and axial runout errors during rotation, because the jaw crusher moves at a spindle speed lower than 300r/mim , So ordinary precision bearings can meet the requirements.
C Bearing internal clearance
Rocket roller bearings only have radial clearance. According to the standard, the radial clearance is divided into five groups, which have been selected and adjusted by the manufacturer before leaving the factory. At this time, the clearance is called the original clearance. After the bearing is assembled, its original clearance will be reduced. For the movable jaw bearing, the eccentric shaft is assembled with it by interference fit. After the movable jaw bearing is heated, the inner ring is expanded and mounted on the eccentric shaft. The expansion of the inner ring will reduce the original clearance of the bearing.
2. Jaw crusher bearings-wear
If the shaft wears very little, it can be turned on a lathe to make the journal to the correct geometric shape just to repair its geometric shape. Then reduce the bearing inner diameter accordingly. However, if the journal size is reduced by 5% compared to the original after several such treatments, turning is not allowed and a new shaft should be replaced.
3. Jaw crusher bearing-installation
a. Check for rust before installation. You can clean it with diesel or kerosene. Then check whether the radial clearance of the bearing, the size and accuracy of the inner hole, and the size of the eccentric shaft assembly journal meet the requirements.
b. Due to the large amount of journal surplus (to the maximum that can be accommodated or withstood) of the equipped bearing, it is generally installed by the hot-fixing method. The bearing is heated to a temperature of about 100°C, and the shaft hole expands to be larger than the journal size After that, the assembly can be carried out. The hot-loading method uses an oil bath for heating, which can ensure that all parts of the bearing are evenly heated without deforming it or reducing its hardness.
c. After the bearing is assembled, use a feeler gauge to check the radial clearance of the bearing after fully cool. Please find the cause in time if it is too small or there is no clearance. If the cause cannot be found, it must be removed and reassembled. If the clearance is appropriate, grease can be applied, and then the other parts can be assembled.
