10 Reasons for Abnormal Temperature Rise of Jaw Crusher Bearings

There are 4 sets of bearings on the jaw crusher, the eccentric shaft and the movable jaw are connected by two sets of bearings, and the eccentric shaft and the frame are connected by two sets of bearings. At present, most of the bearings of jaw crushers use rolling bearings, which have high transmission efficiency and convenient maintenance.

Bearing is an important part of jaw crusher. During production, various problems will inevitably occur in bearings. Abnormal temperature rise is one of the common faults. Here are 10 reasons for the abnormal temperature rise of jaw crusher bearings.

Positions of jaw crusher bearings

Two pairs of bearings are installed on the jaw crusher:

A pair of bearings is installed between the frame and the eccentric shaft, usually called frame bearings, and the frame bearings support the eccentric shaft for rotary motion;

The other pair of bearings is installed between the movable jaw and the eccentric shaft, which is usually called the movable jaw bearing, which supports the movable jaw to swing when the eccentric shaft rotates, so that the movable jaw plate periodically approaches and moves away from the fixed jaw plate.

Two pairs of bearings transfer the crushed material load to the frame when the crusher is running, and are one of the important parts of the jaw crusher.

10 reasons for the abnormal temperature rise of jaw crusher bearings

• 1. The bearing is seriously worn or the cage is damaged

  Once the bearing is worn, over time, the inner ring, outer ring, rolling element, cage, etc. of the bearing will undergo dimensional changes, the bearing clearance will increase, and the running accuracy will decrease, which will cause the temperature of the bearing to increase, the vibration increases, and the noise increases. Seriously, it will lead to heat generation, increased vibration, bearing burning and even bending of the shaft.

• 2. The bearing quality is poor and the original clearance is too small

  If the clearance of the bearing does not reach the specified value, the clearance will be too small after installation, which will cause the bearing to generate heat during the operation and the temperature will gradually increase.

• 3. The axial positioning of the bearing is wrong

  Once there is a problem with the axial positioning of the bearing, the labyrinth ring or the bearing gland is not installed in place, and the eccentric shaft moves to one side during operation, thereby reducing the bearing clearance and causing the bearing to heat up.

• 4. The machining error of the movable jaw bearing hole is large

  The machining error of the bearing hole is large, and the coaxiality exceeds the allowable value, resulting in a large coaxiality error of the outer ring of the bearing after the movable jaw bearing is installed, which will cause the clearance to become smaller and the bearing to heat up.

• 5. There is a problem with the main shaft processing

  The coaxiality error of the journals of the bearings installed on both sides of the main shaft is too large, which exceeds the allowable value of the design. In this way, the coaxiality error of the inner ring after the bearings at both ends are installed is too large, resulting in a smaller clearance and heating of the bearing.

• 6. The axial movement of the fixed bushing occurs

  At this time, the bearing cover on the frame should be removed, the fixing bushing should be locked, the flywheel or groove wheel should be removed, and a new fixing bushing should be replaced.

• 7. The oil hole is blocked, the bearing oil is cut off, and the amount of oil is too little or too much

  These will cause the bearing temperature to rise and cause abnormality. When the equipment is running, read the instructions carefully, and add the lubricating oil on time according to the instructions.

• 8. The machining accuracy of the components does not meet the requirements

  The machining accuracy, especially the machining accuracy of the bearing seat of the equipment parts cannot meet the requirements, is also an important factor that will lead to the temperature rise of the bearings. The machining of the bearing seat hole should ensure the tolerance, roughness and cylindricity of the hole. If the tolerance of the bearing seat hole is too small, the bearing clearance will be too small during the fit, and if the hole tolerance is too large, the fit will be loose, both of which will cause the bearing to heat up.

• 9. Improper selection of lubricating oil

  Bearing lubricants should be selected according to factors such as bearing operating temperature, speed index, load characteristics, and lubrication methods. Improper selection of lubricant, too low or too high viscosity, will both make the lubricating oil difficult to form an oil film, so that the heat generated during the operation of the bearing cannot be taken away, causing the bearing to heat up.

• 10. Non-bearing heating

  The friction heat of the movable jaw seal sleeve and the end cover, or the double-embedded cover of the frame bearing seat and the main shaft rotate together, and the friction heat is generated, which will be considered as abnormal bearing temperature rise. At this time, the end cover and sealing sleeve of the jaw crusher should be replaced, or the upper bearing cover of the heating end of the frame bearing seat should be loosened, and the fuse and the cover should be pressed into the bearing seat groove of the frame, and then the bearing cover should be fixed to eliminate the rotation of the cover.