Spherical Roller Bearings 

The self-aligning roller bearing has double row rollers. The outer ring has one common spherical raceway and the inner ring has two raceways, which are inclined at an angle relative to the bearing axis. This ingenious structure makes it have automatic centering performance, so it is not easy to be affected by the error or shaft bending caused by the angle between the shaft and the bearing housing seat. It is suitable for the occasion of angle error caused by installation error or shaft deflection. The bearing can not only bear the radial load, but also bear the axial load of two-way action.

The inner holes of self-aligning roller bearings are cylindrical and conical, and the taper of conical hole is 1:30 and 1:12. This kind of conical inner hole bearing is equipped with tightening sleeve or withdrawal sleeve, so that the conical inner hole self-aligning ball bearing can be conveniently and quickly assembled on the optical shaft or stepped machine shaft.

Chinese name spherical roller bearing foreign name spherical roller bearing main purpose paper machinery, reducer classification symmetrical spherical roller asymmetric spherical roller features double row roller function automatic centering performance

catalogue

1 Introduction

2 specific introduction

3 structure classification

▪  structure type 

▪  Post code

4 purpose and installation

▪  purpose

▪  install

▪  Clearance

5. Precautions

Introduction to editing and broadcasting

The self-aligning roller bearing has double row rollers. The outer ring has one common spherical raceway and the inner ring has two raceways, which are inclined at an angle relative to the bearing axis. This ingenious structure makes it have automatic centering performance, so it is not easy to be affected by the error or shaft bending caused by the angle between the shaft and the bearing housing seat. It is suitable for the occasion of angle error caused by installation error or shaft deflection. The bearing can not only bear the radial load, but also bear the axial load of two-way action.

The inner holes of self-aligning roller bearings are cylindrical and conical, and the taper of conical hole is 1:30 and 1:12. This kind of conical inner hole bearing is equipped with tightening sleeve or withdrawal sleeve, so that the conical inner hole self-aligning ball bearing can be conveniently and quickly assembled on the optical shaft or stepped machine shaft.

The models of self-aligning roller bearings are: self-aligning roller bearings (20000cc type); Tapered hole self-aligning roller bearing (20000cck type); Self aligning roller bearing (20000cc / W33 type); Tapered hole self-aligning roller bearing (20000cck / W33 type); Self aligning roller bearing installed on the set sleeve (20000cck + H type); There are 6 kinds of self-aligning roller bearings (20000cck / W33 + H type) installed on the tightening sleeve.

Specific introduction to editing and broadcasting

Self aligning roller bearing has two rows of rollers, which mainly bear radial load and axial load in either direction. It has high radial load capacity, especially suitable for working under heavy load or vibration load, but can not bear pure axial load. The outer race of this kind of bearing is spherical, so its centering performance is good and can compensate the coaxiality error.

There are two rows of symmetrical spherical rollers, the outer ring has a common spherical raceway, and the inner ring has two raceways inclined at an angle to the bearing axis, which has good centering performance. When the shaft is bent or installed eccentrically, the bearing can still be used normally. The centering performance varies with the bearing size series. Generally, the allowable centering angle is 1 ~ 2.5 degrees, This type of bearing has large load capacity. In addition to bearing radial load, the bearing can also bear axial load with two-way action, and has good impact resistance. Generally speaking, the allowable working speed of self-aligning roller bearing is low.

Self aligning roller bearings are divided into symmetrical spherical roller and asymmetric spherical roller according to the shape of roller section. Asymmetric self-aligning roller bearings are early products and mainly serve the maintenance of the main engine. Symmetrical self-aligning roller bearings are rarely used in the new design of the main engine. The internal structure has been comprehensively improved and optimized, Compared with the self-aligning roller bearing produced in the early stage, it can bear greater axial load. The operating temperature of this kind of bearing is lower, so it can meet the requirements of higher speed. According to whether the inner ring has retaining edge and the cage used, it can be divided into type C and type ca. the characteristics of type C bearing are that the inner ring has no retaining edge and adopts steel plate stamping cage, CA Tyrion bearing is characterized by retaining edges on both sides of the inner ring and turning solid cage. In order to improve the lubrication of the bearing, the user can be provided with a self-aligning roller bearing with annular oil groove and three oil holes on the outer ring, which is represented by the bearing rear code / W33. The self-aligning roller bearing with inner ring oil hole can also be supplied according to the requirements of users. In order to facilitate the loading, unloading and replacement of bearings, the self-aligning roller bearing with inner hole taper can also be provided. The taper of the taper hole is 1:12 and the later code is K. in order to meet the requirements of special users, the bearing with inner hole taper of 1:30 can also be provided, and the latter code is K30. For the bearing with taper in the inner hole, the locking nut can be used to install the bearing directly on the conical journal, or the bearing can be installed on the cylindrical journal with the help of the locking sleeve or the withdrawal sleeve. In order to prevent harmful slip between raceway and roller due to centrifugal action during high-speed operation of bearing, the bearing shall bear a certain minimum radial load, which can be estimated according to the following formula:

Fr =0.02C

Where:

Fr -- minimum radial load n

C - Basic rated dynamic load of bearing n

Equivalent dynamic load

P = fr + y1fa when fa / FR e

P = 0.67fr + y2fa when fa / FR e

Where:

P-equivalent dynamic load

Y1 Y2 - axial dynamic load coefficient

Equivalent static load

P0=Fr+Y0Fa

Where:

P0 - equivalent static load n

Y0 - axial static load coefficient

Structure classification editing and broadcasting

structure type 

Self aligning roller bearings are divided into cylindrical bore and conical bore. The taper of the tapered inner hole is respectively 1:12 rear self-aligning roller bearing with code K (153000 or 113000) and 1:30 rear self-aligning roller bearing with code K30. When this kind of bearing is matched with the conical shaft, the inner ring moves along the axial direction to adjust the radial clearance of the bearing.

Post code

Install the tapered hole self-aligning roller bearings with rear codes K and K30 on the matching set sleeve to become rear codes K + H and K30 + H bearings. This kind of bearing can be installed on the optical shaft without shaft shoulder, and is suitable for occasions where the bearing needs to be installed and disassembled frequently. In order to improve the lubrication performance of the bearing, an annular oil groove is turned on the outer ring of the bearing and three evenly distributed oil holes are drilled, with the rear code of W33.

Purpose and installation editing broadcast

purpose

Main applicable cages: pressed steel plate reinforced cages (suffix e, few in China). Pressed steel plate type cage (suffix CC), glass fiber reinforced polyamide 66 cage (suffix tvpb), machined brass two-piece cage (suffix MB). Machined brass integral cage (suffix CA), stamped steel plate cage for vibration occasions (suffix JPA). Brass cage for vibration applications (suffix EMA). For the same structure, the codes on the bearings may be different.

Main applications: papermaking machinery, reducer, railway vehicle axle, rolling mill gearbox bearing seat, rolling mill roller, crusher, vibrating screen, printing machinery, woodworking machinery, various industrial reducers, vertical self-aligning bearing with seat.

install

Self aligning roller bearings are equipped with drum roller bearings between the inner ring with two raceways and the outer ring with spherical raceways. The curvature center of the outer ring raceway surface is consistent with the bearing center, so it has the same centering function as the automatic centering ball bearing. In case of deflection of shaft and shell, the load and axial load in two directions can be adjusted automatically. Large radial load capacity, suitable for heavy load and impact load. The inner diameter of the inner ring is a bearing with tapered hole, which can be installed directly. Or install it on the cylindrical shaft with tightening sleeve and disassembly cylinder. The cage uses steel plate stamping cage, polyamide forming cage and copper alloy car cage.

For self-aligning bearings, when installing the bearing with shaft into the shaft hole of the box, the middle mounting ring can prevent the outer ring from tilting and rotating. It should be remembered that the balls of some sizes of self-aligning ball bearings protrude from the side of the bearing, so the middle mounting ring should be recessed to prevent damage to the balls. A large number of bearings are generally installed by mechanical or hydraulic press in method.

For separable bearings, the inner ring and outer ring can be installed separately, which simplifies the installation process, especially when the inner and outer rings need interference fit. When installing the shaft with the inner ring in place into the bearing housing with the outer ring, you must pay attention to check whether the inner and outer rings are correctly aligned to avoid scratching the bearing raceway and rolling parts. If cylindrical and needle roller bearings use an inner ring without flange edge or an inner ring with flange edge on one side, it is recommended to use a mounting sleeve. The outer diameter of the sleeve shall be equal to the inner race diameter F, and the tolerance standard for machining shall be D10. It is best to install the punched outer ring needle roller bearing with a mandrel.

Clearance

For the installation axial clearance of self-aligning 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 self-aligning 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, the axial clearance should be adjusted appropriately. Bearings with low speed and bearing vibration shall be installed without clearance or preloaded. Its purpose is to make the roller and raceway of self-aligning roller bearing have good contact, the load is evenly distributed, and prevent the roller and raceway from being damaged by vibration and impact. After adjustment, the axial clearance shall be checked with a dial indicator. The method is to fix the dial indicator on the machine body or bearing seat, make the contact of the dial indicator against the smooth surface of the shaft, push the shaft left and right along the axial direction, and the maximum swing of the dial indicator is the axial clearance value.

Attention problems editing and broadcasting

The preload of self-aligning roller bearing is carried out at room temperature, but in the working state, the preload of bearing will change due to the drive shaft caused by the rise of micro tensile temperature of the system. Therefore, this factor should be taken into account in setting the preload.

It requires the capacity of the size, speed, and other conditions set by the rational use of self-aligning roller bearing preload to ensure the transmission of life. If the preload is too large, power consumption will be reduced, and even overheating will be caused. If the preload is too small, the body load, shaft rolling and the gap between the outer rings will produce runout, running and transmission accuracy, so as to reduce the increase of noise, affect the gear meshing and seriously damage the teeth and bearings.

According to different self-aligning roller bearing assembly, for example, the bearing preload nut directly compressing the inner ring of the inner bearing in the axial direction rotates the inner and outer rings, so as to eliminate the gap and realize the purpose of bearing preload. Achieve common use: first, far more than the pre installed bearing, the last of the nut, and then back 1 / 4 turn. The advantages of this method are less investment, simple, practical and consistent. Under the premise of excellent quality, tapered roller bearings can be used.

1. Electric heating plate heating method: the bearing can be placed on the electric heating plate with a temperature of 100 ℃ for a few minutes. This method is the most simple. For example, turning over several times can make the bearing bear heat evenly and have high efficiency. This method can be used for large and small self-aligning roller bearings

2. The electric furnace heating method places the bearing in a closed automatic temperature control electric furnace for heating, with uniform heating, accurate temperature control and fast heating. It is suitable for the occasion of heating many bearings in batch

3. Induction heating method uses the induction heater to quickly, reliably and cleanly heat the self-aligning roller bearing to the required temperature, which is especially suitable for the tight fit of the inner ring. Because only the inner ring is heated and the outer ring is rarely heated, it can be easily installed on the shaft and into the seat hole

4. Electric bulb heating method uses 50W electric bulb to heat the self-aligning roller bearing, which can ensure that the heating temperature is about 100 ℃. The smaller bearing can be directly placed on the bulb, and the larger bearing can be placed in the conical cover of the bulb. The conical cover can prevent the heat loss of the bulb and make the heating uniform. The conical cover can be adjusted up and down, and can adapt to heating bearings of different sizes within a certain range. If far-infrared bulb is used, Note that the direction of the bulb should be downward, so as not to harm people's eyes with infrared rays. This kind of bulb can save energy, and the bulb heating method is applicable to a small number of lamps that are not often needed; In case of bearing heating, the bulb can also be used for lighting at ordinary times. In addition, no other equipment is required

5. Oil tank heating method is a widely used traditional heating method. The metal mesh is set at the place 50 ~ 70mm away from the bottom of the oil tank, and the bearing is placed on the mesh. The large bearing should be lifted with a hook, and the bearing should not be placed directly at the bottom of the tank, so as to prevent the local heating of the bearing part contacting the bottom of the tank from being too high, or the dirt precipitated at the bottom of the tank from entering the bearing oil tank. The key points of heating method are as follows. Mineral oil with good non corrosive thermal stability should be used, It is better to keep transformer oil, oil and container clean. The capacity of the oil tank should be determined by the size and oil quantity of the heated self-aligning roller bearing. If the container is too small, the oil temperature will drop quickly as soon as it is put into the bearing during continuous operation, and the effect is not good