Bearing knowledge-Thrust ball bearing
Thrust ball bearings are separated bearings, including shaft ring (with the journal), seat ring (with the housing) and a set of steel balls and cage. When installed, it can be easily fitted with the journal and housing respectively.Thrust ball bearings are separated bearings, including shaft ring (with the journal), seat ring (with the housing) and a set of steel balls and cage. When installed, it can be easily fitted with the journal and housing respectively.
Thrust ball bearings according to the structure of different one-way thrust ball bearings and two-way thrust ball bearings, as well as angular contact thrust ball bearings.
Single direction thrust ball bearings can withstand a direction of axial load, but can not bear radial load. Can do a single direction of axial positioning.
Single direction thrust ball bearing has a plane seat ring and spherical seat ring of the difference. The general plane seat ring is not allowed to have the angle error, but in the support design, can be in the seat ring outer diameter and bearing seat with the surface between the gap of 0.5 ~ 1 mm to compensate. It is also possible to use the thrust ball bearing with aligning seat to compensate for the angular error in the installation. However, the aligning seat needs to be ordered separately.
Double directional thrust ball bearings can withstand axial loads in both directions. However, they cannot withstand radial loads. Can do two directions of axial positioning.
Double directional thrust ball bearing also has a plane seat ring and spherical seat ring of the difference. The general plane seat ring is not allowed to have angle error, but in the support design, can be in the seat ring outer diameter and bearing seat with the surface between the gap of 0.5 ~ 1 mm to compensate. It is also possible to use thrust ball bearing with aligning seat to compensate for the angular error in the installation. However, the aligning seat need.
Angular contact thrust ball bearings mainly bear axial loads, but can also bear a small amount of radial load.
Compared with thrust ball bearings of the same size, the permitted limit speed is higher. Can do a single direction of axial positioning.
Angular contact thrust ball bearing contact angle of 45 ° and 60 ° two, especially suitable for in order to bear axial load, but also a certain radial load of the composite load applications. Can also compensate the plane thrust ball bearing can only bear the axial load and can not bear the radial load deficiency. The structure can bear the size of the radial load, depending on the size of the contact angle, in general, the smaller the contact angle, the greater its ability to withstand radial loads.
The cage of the thrust ball bearing generally adopts the steel plate stamping cage, there are also turned steel, brass solid cage, as well as glass fiber reinforced nylon 66 and other engineering plastic cage.
In order to ensure that the bearing to obtain a good running state, thrust ball bearings with other ball bearings and roller bearings, the same, must be applied to a certain amount of smaller load, especially for high speed, high acceleration, or in the direction of the load has frequent changes in the conditions of work. Because, these working conditions, ball and cage inertia force and friction within the lubricant will have a negative impact on the rolling, rotational accuracy of the bearing, between the ball and raceway may produce a harmful sliding motion on the bearing.
α= 90° P = Fa
α ≠ 90° P = XFr + YFa
Single direction bearings
When α= 45°
Fa/Fr > e X = 0.66 Y = 1 e = 1.25
When α= 60°
Fa/Fr > e X = 0.92 Y =1 e = 2.17
Bidirectional bearings
When α= 45°
Fa/Fr > e X = 0.66 Y = 1 e = 1.25
Fa/Fr ≤ e X = 1.18 Y = 0.59 e = 1.25
When α = 60°
Fa/Fr > e X = 0.92 Y = 1 e = 1.25
Fa/Fr≤e X = 1.9 Y = 0.55 e = 2.17
Equivalent static load
For thrust ball bearings subjected to static loads, the equivalent static loads can be calculated as follows
α= 90° P0 = Fa
α ≠ 90° P0 = Fa + 2.3Fr-tanα
where
Fa – radial load, N
Fr – axial load, N
α – contact angle
X – radial load factor
Y – axial load factor
