What type of bearing seal
In order to maintain good bearing lubrication conditions and normal working environment, full performance of the bearing, prolong the service life of rolling bearings must have suitable sealed to prevent leakage of the lubricant and dust, moisture or other contaminants invasion . Bearing seals can be divided into two categories comes with sealing and additional sealing. The so-called built-sealed bearing is to manufacture the bearing itself to have the sealing performance of the device. Such as bearings with dust cover, ring. This seal is very small footprint, easy installation and removal, the cost is relatively low. The so-called bearing additional sealing means, that is, install the cover and other internal manufacturing a sealing device having a variety of properties. Additional bearing seal selection should consider the following several main factors:
1. bearing lubricant and types (greases and oils);
2. The bearing of the working environment, the size of the space occupied;
3. The axis of the advantages of the support structure, the allowable angle deviation;
The circumferential speed of the sealing surface;
5. bearing operating temperature;
6. The manufacturing cost. Plus seal is divided into non-contact and contact two. Are as follows:
1) Non-contact seals Non-contact seals is to seal its relative movement of the parts are not in contact, and there is adequate clearance seal. This form of seal, in the work of almost no frictional heat, no wear, especially for high-speed and high-temperature applications. Non-contact seals commonly used in various forms a gap type, labyrinth and gasketed and other structures, are used in different situations. Non-contact seals gap to as little better. 2) contact seals contact seals is sealed relative to its moving parts and no contact with the sealing gap. This seal because the seal is in direct contact with a mating member, a large friction at work, heat is also large, easily lead to poor lubrication, the contact surface is easy to wear, causing the sealing effect and performance. Thus, it applies only to the low-speed operating conditions. Contact seals common seal in the form of blankets, cup sealing structure, used in different occasions. According to the working conditions and working environment bearing on the sealing degree requirements, engineering design often use a combination of seal forms, in order to achieve a better seal.
