Vibrating screen is mainly used in stone production, metallurgy, refractory materials, coal and so on. Main screen-box, vibrator, hanging (or supporting) device and the motor and other components. Electric motors via v-belts, spindle drive vibration Exciter, as the vibrator does not balance weights on the centrifugal inertial force, sieves the box vibration, complete material screening.
1. eccentric vibration
Vibrator for vibrating screen, mostly for the eccentric shaft vibration Exciter and box-type vibrator. Easy installation and adjustment of eccentric shaft vibration Exciter, but higher cost, and the offset cannot be adjusted relative position of box vibrator used sector with adjustable eccentric, can realize exciting force size adjustment, so as to achieve the purpose of adjustable amplitude. Vibrator eccentric centrifugal force on the quality of work the eccentric shaft bent, led to the relative deflection of ball bearing ring, due to the eccentricity will have to go and order caused by harmonic vibration, inertia forces generated in the operation and the couple will cause bearing force of inertia and vibrations, undermining the smooth working of bearings and other parts, high frequency vibration. Study analysis shows that when the vibration sieves the box bearing vibration frequency of a first-order natural frequency of the elastic vibration at the same time, strong vibrations from the screen-box elastomers. Bearing with eccentric system vibration system, can be considered a single degree of freedom system. Bearing drive shaft and the driven shaft resonant frequency of the system is the existence of a value, if a certain vibration frequency and resonance frequency is close to, resonance occurs. In addition, due to the bias in the centrifugal inertial force, will therefore have a flexural vibration, if a speed close to the threshold, a bending resonance occurs.
2. Rolling bearing geometric accuracy
Vibrating screen vibrating force, causes the bearing under a radial force, resulting in a strong vibration. Bearings with higher accuracy, vibration is smaller. Especially the rolling surface of the Raceway of the wave effect on vibration of bearing the largest, inner and outer rings and rolling elements and cage surface clearance of rolling and relative movement can cause the vibration of the bearing, which is more frequently due to the rolling spin, working surface with both internal and external Raceway contacts, scroll, rings, cages of the vibrations generated along the lines of 4:3:1. So should first raise the rolling bearing vibration reduction of surface machining accuracy.
3. the radial clearance of bearings
Radial clearance greater than small would produce greater vibration of bearing system. High frequency vibration caused by radial clearance is too small, too low-frequency vibration caused by. Shaker bearing through the test results show that the radial clearance is too large, reduce bearing radial natural frequencies of elastic system, prone to resonance, significant low frequency vibration. This is because the impact of the rolling elements and the ring will have a greater acceleration. At early impact, has nothing to do with mechanical quality and shape of the compression waves, transmitted and metal Interior; later in the impact, a shock wave generated by the mechanical force of low frequency mechanical vibrations. Larger radial internal clearance will exacerbate vibrations on the bearings in the passband.
4. consistent with the
Compatible with the bearing holes in the outer ring can affect transmission of vibration, tighter cooperation would force Raceway deformation, increasing shape errors, lead to increased vibrations. A loose fit can make the gap in the film have a damping effect. Outer ring (housing) difference in supporting the material nature of the hole is large, especially in placing rubber damping ring, can inhibit the transmission of vibrations.
5. the friction and lubrication
Rolling bearing is the main vibration Shaker more difficult to control, since the screen is a great incentive to keep working, so the radial bearing is large, vibrating screen in the course of work, a large exciting force will cause the elastic vibration of bearing system. If poor lubrication, produces larger friction bearing temperature rise too high, excessive thermal expansion, to significantly reduce the radial clearance, which in turn exacerbates the friction, temperature rise further.
Product Model | Inside Diameter | Outside Diameter | Thickness |
NN3944MBKRCC1P4 NSK | 220 | 300 | 60 |
NN3940MBKRCC1P4 NSK | 200 | 280 | 60 |