Tapered roller bearing belongs to separate bearing, and the inner and outer rings of the bearing have tapered raceways. This type of bearing is divided into single row, double row and four row tapered roller bearings according to the number of rows of rollers installed. Single row tapered roller bearings can withstand radial load and axial load in a single direction. When the bearing bears radial load, an axial component will be generated, so another bearing that can bear the axial force in the opposite direction is needed to balance. [1] 

Chinese name tapered roller bearings foreign name tapered roller bearings classification single row, double row and four row type code 30000 joint load under the action of relevant "rolling bearing radial bearing tolerance"

catalogue

1 Introduction

2 Definition

3. Structural features

4 Classification

5 purpose

6 installation

7 parameters

▪  Size range

▪  tolerance

▪  Cage

▪  Allowable error

▪  Suffix definition

Introduction to editing and broadcasting

Tapered roller bearing refers to the radial thrust rolling bearing whose rolling element is tapered roller. There are small cone angle and large cone angle. The small cone angle mainly bears the combined radial and axial load dominated by radial load, which is often used in double and installed in reverse. The inner and outer seat rings can be installed separately, and the radial and axial clearance can be adjusted during installation and use; The large cone angle mainly bears the combined axial and radial load dominated by axial load. Generally, it is not used alone to bear the pure axial load. It can be used to bear the pure radial load when it is used as a pair configuration (opposite installation at the same end).

Define edit broadcast

The ability of single row tapered roller bearing to bear axial load depends on the contact angle, that is, the outer race raceway angle. The greater the angle, the greater the axial load capacity. Single row tapered roller bearings are the most used tapered roller bearings. A small size double row tapered roller bearing is used in the front wheel hub of a car. Four row tapered roller bearings are used in heavy machines such as large cold and hot rolling mills.

Structural features editing and broadcasting

The type code of tapered roller bearing is 30000, and the tapered roller bearing is a separate bearing. In general, especially in GB / T307 The outer ring and inner components of tapered roller bearings within the size range involved in 1-94 tolerance for radial bearings of rolling bearings are 100% interchangeable.

The angle of the outer ring and the diameter of the outer raceway are the same as the overall dimensions and are standardized. It is not allowed to change during design and manufacturing. So that the outer ring and inner components of tapered roller bearing can be interchanged all over the world.

Tapered roller bearings are mainly used to bear the combined radial and axial load dominated by radial load. Compared with angular contact ball bearing, the bearing capacity is large and the limit speed is low. Tapered roller bearing can bear axial load in one direction and limit axial displacement of shaft or shell in one direction. [2] 

Classified editing and broadcasting

Single row tapered roller bearing has an outer ring, and its inner ring and a group of tapered rollers are an inner ring assembly composed of basket cage. The outer ring can be separated from the inner ring assembly. According to the provisions of ISO tapered roller bearing overall dimension standard, the outer ring or inner ring assembly of any standard model of tapered roller bearing shall be able to realize international exchange with the outer ring or inner ring assembly of the same model. That is, for the outer ring of the same model, except that the external dimension and tolerance shall comply with the provisions of iso492 (gb307), the cone angle and cone diameter of the inner ring assembly must also comply with the relevant provisions of interchangeability.

Generally, the taper angle of the outer race of single row tapered roller bearing is between 10 ° ~ 19 °, which can bear the combined action of axial load and radial load at the same time. The greater the cone angle, the greater the ability to bear axial load. For the bearing with large cone angle, the post code plus B, and the cone angle is between 25 ° ~ 29 °, it can bear large axial load. In addition, the single row tapered roller bearings can adjust the clearance size during the installation process.

The outer ring (or inner ring) of double row tapered roller bearing is a whole. The small end faces of the two inner rings (or outer rings) are close, and there is a spacer in the middle. The clearance is adjusted by the thickness of the spacer. The thickness of the spacer can also be used to adjust the pre interference of the double row tapered roller bearing.

The performance of four row tapered roller bearing is basically the same as that of double row tapered roller bearing, but it bears greater radial load and lower limit speed than double row tapered roller bearing. It is mainly used in heavy machinery.

Multi seal double and four row tapered roller bearings. ZWZ provides long-life, multi seal double and four row tapered roller bearings. Carry out personalized new design for the bearing, change the traditional design method of fully sealed bearing, and adopt a new sealing structure combining sealing and dust prevention to improve the sealing effect and sealing performance. Compared with the open structure bearing, the service life of multi seal double and four row tapered roller bearing is increased by 20% ~ 40%; Reduce lubricant consumption by 80%.

Purpose editing and broadcasting

Tapered roller bearings mainly bear radial and axial combined loads. The bearing capacity depends on the raceway angle of the outer ring. The greater the angle, the greater the bearing capacity. This kind of bearing is a separate bearing, which is divided into single row, double row and four row tapered roller bearings according to the number of rows of rolling elements in the bearing. The clearance of single row tapered roller bearing needs to be adjusted by the user during installation; The clearance of double row and four row tapered roller bearings has been given according to the user's requirements when the products leave the factory and does not need to be adjusted by the user.

Tapered roller bearings have conical inner ring and outer ring raceways, and tapered rollers are arranged between them. The projection lines of all conical surfaces meet at the same point of the bearing axis. This design makes tapered roller bearings particularly suitable for composite (radial and axial) loads. The axial load capacity of the bearing is mostly determined by the contact angle α Determined; α The greater the angle, the higher the axial load capacity. The angle is expressed by the calculation coefficient E; The larger the E value, the greater the contact angle, and the greater the applicability of the bearing to bear axial load.

Tapered roller bearings are usually separate type, that is, the tapered inner ring assembly composed of the inner ring with roller and cage assembly can be installed separately from the tapered outer ring (outer ring).

Tapered roller bearings are widely used in automobile, rolling mill, mining, metallurgy, plastic machinery and other industries.

Broadcast editor installation

The following information is provided by kuaiyou automation selection.

Adjust the axial clearance. For the installation axial clearance of tapered roller bearing, the adjusting nut, adjusting gasket on the journal and the thread in the bearing seat hole can be used, or the preload spring can be used to adjust. The size of axial clearance is related to the arrangement of bearings during installation, the distance between bearings and the materials of shaft and bearing seat, which can be determined according to the working conditions.

For tapered roller bearings with high load and high speed, when adjusting the clearance, the influence of temperature rise on axial clearance must be considered, and the reduction of clearance caused by temperature rise must be estimated, that is to say, the axial clearance should be adjusted appropriately.

Bearings with low speed and bearing vibration shall be installed without clearance or preloaded. The purpose is to make the roller and raceway of tapered roller bearing have good contact, the load is evenly distributed, and prevent the roller and raceway from being damaged by vibration and impact. Check the axial clearance with a dial gauge after adjustment.

Installation of four row tapered roller bearings (installation of roller bearings):

1、 The fit between the inner ring of four row tapered roller bearing and the roll neck is generally with clearance. During installation, first install the bearing into the bearing housing, and then install the bearing housing into the journal.

2、 The outer ring of four row tapered roller bearing and the bearing housing hole also adopt dynamic fit. First install the outer ring a into the bearing housing. When leaving the factory, the outer ring, inner ring and inner and outer spacer rings are printed with {hottag} symbols. During installation, they must be installed into the bearing housing in the order of characters and symbols. It cannot be interchanged arbitrarily to prevent the change of bearing clearance.

3、 After all parts are installed in the bearing housing, axially close the inner ring to the inner spacer ring and the outer ring to the outer spacer ring.

4、 Measure the gap width between the end face of the outer ring and the cover plate of the bearing box to determine the thickness of the corresponding sealing gasket.

The multi seal bearing is marked with the post code XRS. [3] 

Parameter edit broadcast

Size range

The basic dimensions of ZWZ tapered roller bearings are listed in the dimensional data sheet,

Single row tapered roller bearing:

Inner diameter range: 20mm ~ 1270mm

Outer diameter range: 40mm ~ 1465mm

Width dimension range: 15mm ~ 240mm

Double row tapered roller bearing:

Inner diameter range: 38mm ~ 1560mm

Outer diameter range: 70mm ~ 1800mm

Width dimension range: 50mm ~ 460mm

Four row tapered roller bearings:

Inner diameter range: 130mm ~ 1600mm

Outer diameter range: 200mm ~ 2000mm

Width dimension range: 150mm ~ 1150mm

tolerance

ZWZ Metric tapered roller bearings have common tolerances and also provide p6x, P6, P5, P4 and P2 tolerance products, all of which are consistent with gb307 1.

ZWZ Inch Tapered roller bearing has common tolerance, and Cl2, CL3, CL0 and cl00 tolerance products can also be provided as required.

Radial clearance

ZWZ single row tapered roller bearing has clearance only after installation, and can be determined only after another bearing positioned in the opposite direction is adjusted.

Cage

Tapered roller bearings generally adopt steel plate stamping and basket cage, but when the size is large, it also adopts turning solid pillar cage.

1. When the outer diameter of the bearing D ≤ 650mm, the steel plate stamping cage shall be adopted, and the rear code of the cage shall not be marked

2. When the outer diameter of the bearing d > 650mm, the steel solid strut cage is adopted, and the rear code of the cage is not marked

Allowable error

equivalent dynamic load 

P = fr kn] when fa / FR ≤ e

P = 0.4fr + yfa [kn] when fa / FR > e

When single row tapered roller bearings are used in pairs (the basic overall dimensions can be different), the additional axial force caused by radial load must be included in the calculation of the equivalent dynamic load of the bearing. The additional axial force s of single row tapered roller bearing can be calculated approximately according to the following formula: S = FR / 2Y

Equivalent static load

Single row tapered roller bearing

P0=0.5Fr +Y0Fa KN]

If P0 < fr, P0 = fr

Double row and four row tapered roller bearings

P = 0fr + y1fa [kn] when fa / FR ≤ e

P = 0.67fr + y2fa [kn] when fa / FR > e

Suffix definition

A: Internal structure change

B: Increased contact angle

10: The overall dimensions adopt international standards

CD: double outer ring with oil hole or oil groove.

TD: double inner ring with taper hole. [4]