The fixation of precision bearings, this question has been asked a lot in recent times, mainly because many people know that, for example, the fixation of bearings requires bearing cages, but the methods and steps for bearing fixation and positioning are still Somewhat puzzled. This article will explain in detail the positioning method and fixed installation steps of the precision bearing fixed bearing.

Positioning method of precision bearing fixed bearing

1. Lock nut positioning method:

When installing the bearing inner ring with interference fit, usually the inner ring side is against the shoulder on the shaft, and the other side is generally fixed with a lock nut (KMT or KMTA series). Bearings with tapered holes are directly installed on the tapered journal, usually fixed on the shaft with a lock nut.

2. Spacer positioning method:

It is convenient to use spacer sleeves or spacer rings between bearing rings or between bearing rings and adjacent parts instead of integral shaft shoulders or bearing seat shoulders. In these cases, dimensional and shape tolerances also apply to related parts.

3. Positioning of stepped shaft sleeve:

Another method of bearing axial positioning is to use stepped bushings. These bushings are suitable for precision bearing arrangements. Compared with threaded lock nuts, they have less runout and provide higher accuracy. Stepped shaft sleeves are usually used for ultra-high-speed spindles, for which traditional locking devices cannot provide sufficient accuracy.

4. Fixed cover positioning method:

When installing the bearing outer ring with interference fit, usually the side of the outer ring is against the shoulder on the bearing seat, and the other side is fixed with a fixing cover. The fixing cover and its fixing screws have a negative impact on the shape and performance of the bearing in some cases. If the wall thickness between the bearing seat and the screw hole is too small, or the screw is tightened too tightly, the outer ring raceway may be deformed. The lighter ISO size series 19 series are more susceptible to this type of damage than the 10 series or heavier series.

Installation steps of precision bearing fixed bearing:

1. Before installing the bearing on the shaft, you must first unplug the fixed pin that fixes the bearing jacket, and at the same time, polish the surface of the journal smoothly and clean, and apply oil to the journal to prevent rust and lubricate (allow the bearing to rotate slightly on the shaft) .

2. Apply lubricating oil on the mating surface of the bearing seat and bearing, and install the double-row tapered roller bearing into the bearing seat. Then put the assembled bearing and bearing seat on the shaft and push it to the desired position for installation.

3. Do not tighten the bolts that fix the bearing seat, and make the bearing housing rotate in the bearing seat. Also install the other bearing and seat on the same shaft, rotate the shaft a few times, and let the fixed bearing automatically find its position. Then tighten the bearing seat bolts.

4. Install eccentric sleeve. Put the eccentric sleeve on the eccentric step of the bearing inner sleeve first, and tighten it by hand in the direction of rotation of the shaft. Then insert the small iron rod into or against the counterbore on the eccentric sleeve. Knock the small iron rod along the axis of rotation with a hand hammer. Install the eccentric sleeve firmly, and then tighten the hexagon socket screws on the eccentric sleeve.