Clutch release bearing is an important part of automobile clutch system, which realizes the combination and separation between engine and transmission system through axial movement. According to different classification standards, clutch release bearings can be divided into various types. The following is a detailed introduction to the types of clutch release bearings:

I. Classification according to the function principle

1. Push-type clutch release bearing: this kind of bearing realizes clutch separation and combination by being pressed by the thrust force to the clutch release finger (lever). 

It is usually used in occasions that require large thrust force to release the clutch.

2. Pull Type Clutch Release Bearing: In contrast to the push type, the pull type bearing achieves clutch release by pulling on the clutch release finger (lever). 

This type of bearing is more common in some specific design of clutch system.

II. Classification according to structural type

1. Non-aligning clutch release bearing: This type of bearing does not have the function of self-aligning and needs to be installed to ensure that the axis is accurately aligned with the axis of the clutch system. 

Non-aligning bearings include push type and outer ring rotation, push type and inner ring rotation and other types.

2. Self-aligning clutch release bearings: These bearings are capable of automatically adjusting axial deviations to a certain extent, thus minimizing the effect on clutch performance of axial deviations due to installation errors or during use. 

Self-aligning bearings also include push type and pull type two types.

III. Classification according to sleeve material

Clutch release bearing sleeve material is also an important basis for its classification. Common sleeve materials include engineering plastics, low plastic steel, cast iron, cast steel, powder metallurgy and bearing steel. Different materials have different performance characteristics of the sleeve, such as wear resistance, corrosion resistance, strength, etc., suitable for different use of the environment and working conditions.

IV. According to different designs and applications, clutch release bearings can be mainly categorized into the following types:

1. Traditional release bearings (Standard Release Bearings):

   - This is the most basic type, which is directly connected to the release fork or hydraulic slave cylinder and is used to push the release lever or act directly on the pressure plate to release the clutch.

   - They may require periodic lubrication to minimize wear.

2. Self-Aligning Release Bearings (SARBs):

   - Designed with an internal structure that automatically adjusts the alignment with the release lever or pressure plate to work effectively even with slight misalignment.

   - This design reduces wear and noise caused by misalignment.

3. Integrated or Unitized Release Bearings:

   - The release bearings are integrated with the release forks or other components to form a single unit.

   - This design simplifies the installation process, reduces connectivity problems between components, and improves reliability. 

4. Hydraulically Actuated Release Bearings:

   - In some modern vehicles, the release bearing is directly coupled to the hydraulic system and does not require a mechanical connection.

   - This design, often referred to as a clutch slave or slave cylinder, is directly actuated by hydraulic pressure, which reduces operating forces and improves responsiveness.

5. Silent Release Bearings:

   - Special materials or designs, such as increased internal lubrication or the use of low friction materials, are used to reduce noise during operation.

   - These bearings are particularly suitable for vehicles that require low noise levels.

6. Sealed or Long-Life Release Bearings:

   - A fully sealed design, filled with long-life grease, reduces the intrusion of external contaminants and extends service life.

   - This design reduces maintenance requirements and is suitable for locations that are difficult to access or costly to replace.

V. Specific Model Examples

Taking a brand clutch release bearing as an example, its model number may contain the following information:

Contact ring diameter: indicates the size of the diameter of the part of the bearing in contact with the clutch release finger (lever).

Contact surface shape: such as arc or plane (plane usually do not note code).

Bearing type designation: e.g. T for push type clutch bearing, WT for non-aligning - push type - outer ring rotating clutch bearing unit, etc.

Unit inner diameter: indicates the size of the diameter of the inner ring of the bearing.

Unit mating width: indicates the width of the mating part of the bearing and clutch system.

Sleeve material designation: As mentioned earlier, indicates the type of material of the bearing sleeve.

In summary, there are various types of clutch release bearings, which can be applied to different automotive clutch systems and use environments according to the different function principles, structure types, sleeve materials and specific models. Each type has its specific application scenarios and advantages, and the selection of the right release bearing depends on the design of the vehicle, the conditions of use and the preference of the repairer. When replacing, the manufacturer's recommendations should be followed to ensure optimum performance and longevity of the clutch system.