What are the different types of bearings used in mixers?
Mixer drive systems are subjected to both axial (thrust) and radial loads during operation. The type and magnitude of load depends on the mixer geometry and the materials being mixed. Accordingly, bearings are selected for transmission of the loads. The following are the different types of bearing used in mixers.
- Self aligning ball bearings
- Deep groove ball bearings
- Angular contact ball bearings
- Cylindrical roller bearings
- Spherical roller bearings
- Tapered roller bearings
- Thrust ball bearings
- Pillow block bearings
- Plummer block bearings
Self aligning ball bearings
Self-aligning ball bearings are of the double row type, with a spherical outer ring raceway. Their self-aligning capability allows compensation for misalignment, agitator shaft deflections, and housing deformations. Self-aligning ball bearings are available in cylindrical and tapered bore design. The bearings are not separable.
Deep groove ball bearings
Single row deep groove ball bearings are suitable for both radial and thrust loads. These bearings can be used for high speed mixer operations. Sealed deep groove ball bearings are easy to install and maintain. The capabilities of these bearings and their competitive price make them a popular choice for mixers. The self-aligning capacity of deep groove ball bearings is limited. Deep groove ball bearings are inseparable.
Angular contact ball bearings
Single row angular contact ball bearings are suitable for both radial and thrust loads. They accommodate thrust loads in only one direction; therefore, they are adjusted against another bearing which accommodates the opposite thrust load. Angular contact ball bearings are suitable for high speeds. Their self-aligning capability is limited. Angular contact ball bearings are inseparable.
Cylindrical roller bearings
Single row cylindrical roller bearings are separable. This design facilitates easy mounting and removal. Both the bearing rings can be given a tight fit. The modified line contact between rollers and raceways eliminates edge stressing.
Spherical roller bearings
Spherical roller bearings are used for heavy duty mixers, such as those used for viscous materials. They feature two rows of symmetrical barrel rollers which can align freely in the spherical outer ring raceway. This design ensures compensation for shaft deflections and misalignment of the bearing seats. Spherical roller bearings have long rollers with a large diameter. The close contact between the rollers and raceways results in a uniform stress distribution and a high load carrying capacity.
Tapered roller bearings
Tapered roller bearings are capable of handling high radial and axial loads. As tapered roller bearings transmit axial loads only in one direction, a second, symmetrically arranged tapered roller bearing is provided for counter guidance. Tapered roller bearings are commonly used in kneader extruders. Tapered roller bearings are of separable type. The cone with the roller and cage assembly, and the cup can be mounted separately. The modified line contact between rollers and raceways eliminates edge stressing.
Thrust ball bearings
Thrust ball bearings are made as single and double direction bearings. These bearings have the capability of handling high axial loads; however, they are not suitable for radial loads. In addition to the design with flat washers, thrust ball bearings with spherical housing washers and seating washers are also available.
Pillow block bearings
Pillow blocks are housings which have a bearing fitted into them. The advantage of pillow blocks is that there is no need to manufacture a separate bearing housing for the mixer. Their use is limited to applications where the magnitude of load is small, and for clean operating environments.
Plummer block bearings
Plummer blocks are readily available bearing housings suitable for installing standard bearings. These are used for higher load ratings and corrosive industrial environments.
While selecting bearing for mixing equipment, it is essential to have accurate information on the load-carrying capacity of the bearings and their expected operational life.
Unique Mixers & Furnaces Pvt Ltd
Contact Person: Mr Jayesh R Tekchandaney
Phone – +91-22-25801214/25822385