Single Direction Thrust Ball Bearings

Detail Introduction :

Single direction Thrust ball bearings is one of the indispensable parts of many machines, by a shaft ring, a seat ring and a steel ball, cage assembly.

It is worth noting that Single direction Thrust ball bearing can only withstand a single direction of axial load, and can make a single direction of axial positioning, but can never withstand any radial load.

SKF bearings are commonly used mainly because of its advanced manufacturing technology, all SKF bearings have a strong and durable, low friction, can simultaneously withstand radial and axial loads, high and low temperature conditions can be used and other advantages.

Single direction Thrust ball bearings as the bearing industry in the well-known brand Skf production research and development of one-way thrust ball bearings, in the global scope have a stable market network, for the development of the world industry provides a strong technical support.

Single direction Thrust ball bearing is also a smaller size bearing, one is the bearing seat ring with a flat bottom seat cushion, another is the spherical seat cushion shape. Bearings with spherical rings can be used together with spherical cushions to compensate for misalignment between the bearing housing and the bearing surface of the shaft.

Single direction thrust ball bearings are used in a wide range of applications, mainly in gyro rotors, micro motors and other devices with high requirements for dynamic balance, noise, vibration and stability.

And Single direction Thrust ball bearings simplify the structure around the imported bearings, easy maintenance, inspection, generally can simultaneously withstand radial load and axial load, relatively easy to use under high and low temperature conditions, in order to improve rigidity, even in the negative clearance that is pre-load state can also be used. 

Single direction thrust ball bearings have a total of one-way, two-way types.

Single direction Thrust ball bearings features.

1, whether one-way or two-way, can choose spherical spherical spherical seat cushion type or with a spherical seat ring type, to a certain extent to allow the installation error.
2, SKF bearings are made of high-quality steel, can make the bearing life up to 80% of the super clean steel.
3, choose high-quality grease technology-SKF's lubricant technology can make the life of the grease extended and improve the performance of the bearing.
4, high-grade steel balls - quiet and smooth at high speed rotation.
5, and Single direction Thrust ball bearings using the option of the collar, can allow for mounting errors.

Thrust ball bearings are designed to withstand thrust loads at high speeds and consist of a washer-like collar with ball rolling raceway grooves. Because the collar is seat cushion shape, therefore, the thrust ball bearing is divided into flat bottom seat cushion type and spherical spherical seat cushion type two types. In addition, this bearing can bear the axial load, but can not bear the radial load.

Of course, one-way thrust ball bearings are used to bear axial load mainly shaft, radial combined load, but the radial load shall not exceed 55% of the axial load, compared with other thrust roller bearings, such bearings have a lower friction factor, higher speed, and has a spherical performance.

Because SKF bearings involved in the extremely wide range, the maximum extent to meet the needs of customers, of course, in the installation of high-speed precision SKF Single direction Thrust ball bearings also need to pay attention to the following matters, so as to extend the bearing life.

When installing SKF Single direction Thrust ball bearings, it should be done in a dust-free and clean room to ensure that there is no dust contamination during the installation process; special tools should be used to install the bearings to ensure that they are evenly stressed; the bearings should be placed in a place where the humidity does not exceed 65% to prevent rust on a regular basis.

The following is a more detailed description and introduction of Single direction Thrust ball bearing.

1.Single direction Thrust ball bearings Designs and variants

Single direction thrust ball bearings
1.consist of a shaft washer, a housing washer and a ball and cage assembly (fig. 1)
2.can accommodate axial loads and locate a shaft axially, in one direction only

Double direction thrust ball bearings
consist of one shaft washer, two housing washers and two ball and cage assemblies (fig. 2)
The housing washers and ball and cage assemblies of double direction bearings are identical to those used in single direction bearings.
can accommodate axial loads and locate a shaft axially, in both directions

Bearings with sphered housing washers
1.can accommodate initial misalignment
2.are available in both single (fig. 3) and double direction designs
3.can be used together with a sphered seat washer adjacent to the housing washer (fig. 4 and fig. 5) or adjacent to a machine component manufactured with a sphered surface

Appropriate sphered seat washers must be ordered separately (product tables). Depending on the bearing series, they have the basic designation U 2, U 3 or U 4 followed by a two-digit number, which identifies the size, e.g. sphered seat washer U 320 for bearing 53320).

Cages

 table 1

2.Single direction Thrust ball bearings Permissible speed
The speed ratings in the product tables indicate:
1.the reference speed, which enables a quick assessment of the speed capabilities from a thermal frame of reference
2.the limiting speed, which is a mechanical limit that should not be exceeded unless the bearing design and the application are adapted for higher speeds

3.Single direction Thrust ball bearing Bearing data
 

The bearing also has a limited temperature under the specified operation. The limited temperature of the bearing depends on the material of the bearing. Excessive temperature is also harmful to the bearing. The following is the limit on the bearing temperature.

4.SKF Single direction Thrust ball bearings Temperature limits

The permissible operating temperature for thrust ball bearings can be limited by:
1.the dimensional stability of the bearing washers and balls
2.the cage
3.the seat washer(s)
4.the lubricant

Where temperatures outside the permissible range are expected, contact SKF.

Bearing washers and balls
Depending on their size, washers and balls of SKF thrust ball bearings are heat stabilized up to:
1.125 °C (260 °F) where d ≤ 300 mm
2.150 °C (300 °F) where d > 300 mm

Cages
Steel and brass cages can be used at the same operating temperatures as the bearing washers and balls.

Seat washers
Seat washers are made of steel and can be used at the same operating temperatures as the bearing washers and balls.

Lubricants
For temperature limits of SKF greases, refer to Selecting a suitable SKF grease.
When using lubricants not supplied by SKF, temperature limits should be evaluated according to the SKF traffic light concept.

5.SKF Single direction Thrust ball bearings Mounting
Where mounting a single direction thrust ball bearing, it is important to differentiate between the shaft washer and the housing washer. The bore of the shaft washer is ground and always smaller than the bore of the housing washer. The shaft washer should always be placed against a shaft step or fixed shaft component.

Complete guide to SKF Single direction Thrust ball bearing.

Bearings have become an essential part for the development of modern industrial industries, and SKF has a very good application as an outstanding bearing manufacturer.
The following are common questions and answers about SKF Single direction Thrust ball bearings.

1.What is SKF Single direction Thrust ball bearings?

Single direction thrust ball bearings consist of a shaft ring, a seat ring and a steel ball and cage assembly. Single direction thrust ball bearings are separated type, shaft ring, seat ring, steel ball - cage assembly can be installed separately. Single direction thrust ball bearing, can withstand single direction axial load, and can make single direction axial positioning, but never can bear any radial load.

2.Single direction Thrust ball bearings allowable speed is what?

Each kind of bearing has a permissible speed, a one-way thrust ball bearing speed may be higher than the reference speed, but not higher than the value of the limit speed. In the development of thermal permissible speed, should be fully considered the influence of the special working environment. If a one-way thrust ball bearing directly side by side installation to take special measures to achieve a high speed of a single bearing.

3.One-way thrust ball bearings and flat bottom thrust ball bearings what is the difference

Single direction thrust ball bearings and flat bottom thrust ball bearings is actually a one-way and two-way difference.
Single direction flat bottom thrust bearings are generally composed of a row of steel balls (with cage), a shaft ring (and shaft tight fit) and a seat ring, and its seat ring and shaft clearance and bearing seat hole is a tight fit, and its steel balls in the middle of the shaft ring and seat ring to do rotary motion.

The main difference is Single direction Thrust ball bearings can only bear a direction of the axial load, and completely can not bear the radial load. And because the axial load it is uniformly distributed in each steel ball above, so the one-way flat bottom thrust ball bearing load capacity is quite large; but also because in the work, its temperature rise will be relatively large, so it allows the limit speed is not high.

Although the one-way flat bottom thrust ball bearing can not limit the radial movement of the shaft or shell, but it can limit the axial movement of the shaft and shell in the same direction, so such bearings are often used in combination with deep groove ball bearings will have better results.

4.Single direction Thrust ball bearings What are the installation considerations?

When the technician does the installation, the axis of the shaft and housing hole must be kept concentric, otherwise it will produce stress concentration causing premature damage to the bearing. If you want to prevent this undesirable phenomenon, then you can leave a certain gap between the outer diameter of the seat ring and the housing hole, preferably in 0.5 ~ 1mm radial clearance.

It is worth noting that its shaft centerline and shell support surface should maintain a certain vertical slenderness, of course, does not allow the shaft in the work of tilt or deflection phenomenon, which will cause uneven load distribution, and then cause premature damage to the bearing. How can we eliminate the bearing axis tilt it, researchers have shown that the support surface in the seat ring, pad some elastic materials, such as oil-resistant rubber, leather, etc., or the use of thrust ball bearings with spherical seat.

5.Single direction Thrust ball bearings structure form

Single direction flat bottom thrust ball bearings it also belongs to the separation type bearings, it can also be classified according to its structure form: one-way thrust ball and two-way thrust ball bearings. Single direction thrust ball bearings it can only withstand a direction of load, and still axial load, while two-way thrust ball bearings it can withstand two directions of axial load.

Both of them can not bear radial load. And thrust ball bearing or belong to the structure with seat cushion form, and because its seat cushion mounting surface is spherical, seat bearing has a certain spherical performance, but also can reduce the impact of the error when installed. One-way flat bottom thrust ball bearings are mainly used in automotive, machine tools and other industries.

6.What is the effect of vibration on the one-way thrust ball bearing?

During normal use, vibration damage to the bearing is quite sensitive, spalling, indentation, rust, cracks, wear, etc. will be reflected in the bearing vibration measurement.

Therefore, by using a special bearing vibration measuring device (frequency analyzer, etc.), the magnitude of vibration can be measured, and the frequency distribution can be used to deduce the specific situation of abnormalities. The measured values vary depending on the conditions of use of the bearings or the location of the sensors, so it is necessary to analyze and compare the measured values of each machine beforehand to determine the judgment criteria.

7. What are the effects of temperature on Single direction Thrust ball bearings?

Prolonged use of the bearings can put the bearings in abnormal conditions and is also harmful to the bearing lubricant. Sometimes bearing overheating can be attributed to the bearing lubricant. If the bearing in more than 125 ℃ temperature for a long period of continuous rotation will reduce the bearing life. Causes of high temperature bearings include: insufficient or excessive lubrication, lubricant. Containing impurities, excessive load, bearing damage, insufficient clearance, and oil seal generated by high friction, etc..

In the process of using the bearing is easy to appear the phenomenon of temperature rise. When the bearing temperature rises, first determine whether the misoperation, such as indeed rising, should be done as follows.
1, check the cooling water pressure, water flow and piping system is normal. If the water pressure is low may be filter blockage, can not be timely processing, can stop processing, when confirmed to work, and then put into use.
2, should check the oil pressure of the governor, if the oil pressure is low may cause the cooling water hydraulic valve to close.
3、Check whether there is any noise in the bearing, and detect whether there is any abnormality in the bearing swing.
4、Take an oil sample to observe whether there is any change in oil color, and conduct a laboratory test to see if it is deteriorated. If it is confirmed to be deteriorated, it should be stopped and replaced with new oil.
5、Check whether the oil level of the oil mark is normal, if not normal, check whether the oil tank drain valve is closed. If it has been closed tightly, oil should be replenished, if the gasket is seeping oil, it should be shut down.

8.What is the role of Single direction Thrust ball bearing?

Single direction thrust ball bearing is only applicable to the machine which bears axial load on one side and low speed, such as crane hook, vertical water pump, vertical centrifuge, jack, low speed reducer, etc.

The shaft ring, seat ring and rolling body of the bearing are separated and can be assembled and disassembled separately. Moreover, the thrust ball bearing is designed to withstand thrust load at high speed and consists of a washer-like collar with a ball rolling raceway groove. Because the collar is seat cushion shape, therefore, the thrust ball bearing is divided into two types: flat bottom seat cushion type and spherical seat cushion type. In addition, this bearing can bear axial load, but can not bear radial load. It is only suitable for bearing axial load on one side and low speed, such as crane hook, vertical water pump, vertical centrifuge, jack, low speed reducer, etc.

The shaft ring, seat ring and rolling body of the bearing are separated and can be assembled and disassembled separately. ## One-way and two-way refers to the parallel and perpendicular to the axis of the two directions, some shaft in motion in both directions will be subject to force, so it is necessary to bearing in both directions can withstand the force of the shaft.

9. Price standard of Single direction Thrust ball bearing.

The price of the bearing is about several dozens of dollars per set, the cheap ones are more than ten or twenty dollars, the expensive ones are one or two hundred dollars, and the price varies for different functions and uses of the bearing. The price is based on a number of factors. Good quality is naturally more expensive, but it is also very reasonable and good value for money.

The type of bearing, the material of the parts used will determine the life, reliability and performance of the bearing, but there are many factors that affect the performance of the bearing, including the choice of bearing capacity, rolling contact conditions, as well as the cleanliness of the operating environment and the dimensional stability of the bearing parts, and the price of all aspects are very good to be relatively high. 

The selection of ball bearing needs to consider the rolling body type, rolling body column number, use, cage and its material, bearing material, type, use characteristics, outer diameter, inner diameter and other factors. For example, bearing material has high temperature bearing steel, etc.; cage and its material has Y copper plate stamping, J steel plate stamping, F1 carbon steel, etc.; usage has general, engineering machinery, automobile wheel, rolling mill, machine tool spindle, etc.

10. What are the advantages of Single direction Thrust ball bearing?

1. Thin-walled bearing thin-walled ring bearing high precision, very quiet and strong bearing capacity.
2. SKF ball bearings are available in three designs and are extremely small and mostly square in cross section.
3.In all SKF series, the cross section remains the same even for larger shaft diameters and bearing holes.SKF bearings are therefore called equal cross section (CS). It is this feature that distinguishes the thin-walled rings in the standard ISO series from conventional bearings.

Nowadays, there are more and more high-end bearings, but when choosing a bearing, the bearing that suits your machinery is the most important.

11.What is the application range of Single direction Thrust ball bearing?

Single direction Thrust ball bearings are widely used in machine tool spindles, high frequency motors, combustion turbines, centrifugal separators and other machines.

But Skf bearings are very diverse, almost configured with a full range of general-purpose bearings and bearings for specific users, more than 1800 types, including deep groove ball bearings, cylindrical roller bearings, spherical roller bearings, tapered roller bearings, angular contact ball bearings, thrust bearings, self-aligning ball bearings, needle roller bearings, linear bearings, guide bearings, joint bearings and bearing housings and many different products.

In fact, different types of bearings are used for different purposes, but in general, they play a supporting role. The essence of support is to be able to bear radial load, can also be understood as a fixed shaft, so that the shaft can only achieve rotation, and control its axial and radial movement. Simply put, the bearing can only play a load-bearing role, but can not play a transmission role, but also has a certain role in reducing friction.