Roller Bearings Grease Seal Way

Time：2020.10.15  Source：Roller Bearings Suppliers

In order to provide the running speed of the bearing at work, grease or lubricating oil is generally used to lubricate the bearing. How about sealing lubricant when we lubricate the bearing with grease?According to the use of different types of bearings, the bearing grease sealing way will be different.

Different sealing methods of grease may lead to unstable temperature rise, abnormal temperature rise, long initial running in time, and even sintering. Therefore, it is necessary to adopt appropriate grease amount and correct sealing method according to the service conditions.

1. Confirmation before sealing

Make sure there is no residue left inside the bearing.It is recommended to use bearings for high speed spindle in the order of cleaning, degreasing and sealing in grease.Other conditions of use, it is also recommended to remove the attachment to the bearing inside the anticorrosive oil.Need WSBC 22310 E,click here to learn more.

2. Sealing in grease

It is recommended to use a packer in order to seal the proper amount of grease.Packer, preferably a gauge with a seal reading.

3. Sealing amount of grease

Standard recommended sealing amount for precision bearing:

Angular contact ball bearings for high speed spindles -- 15% (-2%~+2%) of intervolume

Cylindrical roller bearings for high-speed spindles -- 10% (-2%~+2%) of intervolume

Ball bearings for motors -- 20%~30% of space volume.

Sealing method of bearing grease:

1. Grease sealing method for ball bearings

(1) Seal evenly between the steel balls.If the guide of the cage is an outer ring guiding the phenol resin cage, it is recommended to apply thinly grease to the guide surface of the cage.

(2) Turn the bearing by hand to seal the grease evenly into the raceway surface, the inside diameter of the cage, between the steel balls and the guide surface, so that the grease fills the internal space.

2. Grease sealing method for cylindrical roller bearings

(1) Apply 80% of the sealed oil evenly on the rolling surface.At this point, it is recommended that the inside diameter of the cage not contain too much grease.The grease inside the cage is difficult to flow in the initial run-in and running stage, which increases the temperature rise and also extends the run-in and running time.

(2) Apply the grease on the roller rolling surface to the end face of the roller, the cage, the contact part with the roller, and the inlet of the pocket, so that the grease can be evenly distributed to the whole bearing.

(3) Apply 20% of the sealed amount of grease evenly to the racetrack surface of the outer ring covering the bearing room.Click here to learn more about WSBC 22224-E1.

It is necessary to select the grease according to the working temperature of the rolling bearing.The temperature range of grease varies with the type of grease.The upper service temperature limit of a grease depends primarily on the type of base oil and thickener, while the lower service temperature depends primarily on the type and viscosity of the base oil.Common calcium base greases are generally based on mineral oils, and their temperature is -10~60℃, which can only meet the general operating temperature requirements.

For lithium base grease suitable for rolling bearings, the upper limit of service temperature generally does not exceed 120℃, while the lower limit of service temperature varies with base oil.The lower limit of service temperature of lithium grease based on mineral oil is generally not lower than -20℃, while the lower limit of service temperature of lithium grease based on synthetic oil can reach -40~-60℃.

Therefore, the operating temperature range of the rolling bearing should be basically the same as that of the grease in order to meet the operating requirements.Of course, in addition to the operating temperature range, other operating conditions such as speed, load, etc. are also important factors in the selection of grease.