The main factors affecting bearing life
Vibratory Separator run on the exciting force generated by the high speed rotation of the vibration exciter. When the vibration exciter works, the movement track of it is a complex three-dimensional curve, the movement track of material can be changed and increase or decrease the residence time of materials stayed on the sifter by adjusting the phase angle of the upper and nether eccentric blocks, to achieve the expected screening results. It can be seen that the anti-friction bearing of the vibration exciter is not only subject to the impact force that varies in size and direction with regularity, but also affected by radial and axial load. It has higher requirements on bearing material and structure as well as the clearance of bearings, the grade of fit between bearings and journal and housing holes. If not, the life of bearing will be affected.

The bearing selection--The bearings used in domestic Vibratory Separator are general bearings just as other vibration equipment selected, which have definite limitations in bearing capacity and service conditions and can be used under general conditions. However, the effect is less than satisfactory when it was used as a vibratory equipment, the life of bearing will be reduced. Generally, the contradiction is solved by enlarging the bearing specification. The vibration exciter is the heart of Vibratory Separator, improper bearing selection will affect the uses of sieve machine, so it’s the precondition of choosing the proper bearing to ensure the normal operation of Vibratory Separator.
The proper fit--When Vibratory Separator works, the bearing of the vibration exciter rotates at a high speed, and the load on the bearing outer ring is rotating load, that is, the outer ring rotates relative to the load direction. Meanwhile, the load has a great impact. To avoid the bearing amplify the impact to the bearing housing in the working process and cause the rotation of the outer ring of the bearing and do heat damage to bearing, the interference fit should be used in general of the outer ring of bearing. The interference cannot too large, otherwise it will decrease the internal clearance of bearing until completely disappear, create the exaggerated contact stress and increase friction heat, resulting in faster wear of the bearing, so as to reduce the life of the bearing.
Poor heat dissipation in bearing room of axis is the outcome of continuous operation of Vibratory Separator under the general condition, and the axis’s temperature rise to be higher than the bearing housing. To prevent the thermal expansion and bearing jamming, there should be a definite margin in the process of axis. But the margin cannot be too large, or it will cause axial movement.
The appropriate lubrication--The purposes of bearing lubrication are that reduce friction, prevent or alleviate abrasion, carry off the frictional heat by lubricating oil and keep off corrosion. The lubricating oil is the blood that can keep bearing maintain normal work. When oil mass . is too small, the bearing will not be well lubricated, which will lead to increased friction, temperature rise, eventually the bearing burned. But it can not be filled too full, or the bearing will be damaged by the temperature rising and the resistance increasing, and the oil injection amount is generally 1/2 of the bearing housing. So it’s the necessary requirement to make sure the bearing operate normally that choosing the adequate and suitable lubricating oil.
The practical application
Some users do not refuel, change oil and clean the bearing according to the related requirements of the operation manual of Vibratory Separator in the process of use. The premature failure of bearing is the result of improper maintenance.
When the bearing needs to be replaced, improper or unqualified bearing may be replaced, or the bearing housing may be strayed into some impurities in the replacement processing. The normal using effect of the bearing may be affected and so as to fail to achieve the expected bearing life.
Due to the restriction of the objective condition, some Vibratory Separators cannot contact with the ground directly in the process of using, and usually be placed on a support frame. The resonance will occur because of not enough to fracture intensity of support frame, the screening machine will work under the unstable condition, and intensify the bearing failure , and shorten the service life of bearing and cause the vibration exciter to be scrapped.