Problem with applying lubricant

Not all bearings filled with grease must have oil filling holes and vent holes. The lubrication and sealing methods for bearings vary depending on the type of bearing, the application environment, and design requirements, and different configurations may be used. Some bearings are designed with ease of lubrication in mind; as such, they may include oil filling holes and vent holes to facilitate the addition and replacement of grease, while also preventing excessive pressure from being generated inside due to the compression of the grease. However, there are some bearings that are sealed; they are typically filled with an adequate amount of lubricant at the time of manufacture, and this lubricant continues to function throughout the bearing’s service life. As a result, such bearings do not have oil filling holes or vent holes. For this type of bearing, users generally do not need (and should not) add or replace lubricant on their own. In bearing applications that require regular addition or replacement of lubricant, there are indeed some bearings equipped with oil filling holes and vent holes. The oil filling hole is used to fill the bearing with grease, while the vent hole allows excess grease and gas to be expelled, preventing an increase in internal pressure caused by an excessive amount of grease. If you are not sure whether your bearing needs lubricating grease or how to lubricate it properly, the best approach is to consult the bearing’s user manual or contact the bearing manufacturer for professional guidance. They usually provide detailed lubrication instructions and maintenance recommendations. Without clear guidance, it is not recommended to lubricate the bearings on your own to avoid causing damage. .

It is recommended to consult the device’s user manual or contact the manufacturer. Additionally, there are many types of this kind of oil injection method; it would be best to send a video for easier discussion, as a reference.

The concerns you have are valid; it’s not necessarily necessary to have oil vents – as long as there is a way to allow air and oil to escape, that’s sufficient. Typical mechanical design manuals contain diagrams.

The bearing chamber is not completely sealed; when you apply grease, you can see the old grease being forced out

Firstly, those that use grease do not necessarily require regular greasing, such as some low-power electric motors； Secondly, if fat injection is needed, there will definitely be an injection port, but there may not necessarily be a port for removing fat; the main goal is to ensure that old fat is removed~