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The bearing with double-sided seal can not only preserve the grease, but also prevent foreign matters such as dust from entering the fag bearing and keep the rolling element rotating in a clean environment. This kind of bearing is mostly used in occasions with poor service environment and inconvenient maintenance and repair.
At present, the commonly used structural form is crimped dust cover. After the bearing is filled with lubricating grease, press the dust cover. The dust cover is deformed and fixed in the tooth mouth of the outer ring with die ina bearing. Generally, the dust cover can no longer be removed after being pressed. If the dust cover is to be removed, it will be scrapped. Because there is a gap between the inner diameter of the dust cover and the inner ring of the bearing, the lubricating grease cannot be completely sealed in the bearing, and too small dust or foreign matters cannot be blocked out, so the sealing effect is less. Because the dust cover is press installed in the bearing, the dust cover rarely falls off, the sealed NTN bearing structure is firm, and the heat dissipation is better than the contact seal.
The sealing forms of non-contact sealing ring and dust cover are similar. There is a suitable clearance between the inner diameter of the sealing ring and the outer diameter of the bearing inner ring, which can prevent most of the grease from leaking into the NSK bearing and large particles of dust from entering the bearing; As the name suggests, the inner diameter of the contact seal ring is in contact with the outer diameter of the inner ring. This method can effectively prevent the leakage of lubricating grease and prevent external dust and liquid from entering the bearing. However, due to contact, some heat will be generated and serious wear will be caused.