How to install the bearings correctly?
Author: hongyuanTime:
The correct installation of the bearing directly affects the accuracy, life and performance of the bearing when it is used. This article shares several tips and precautions for bearing installation.
①Bearing installation tips
▶ Installation with copper rod and manual hammering
This is an easy way to install small and medium-sized bearings. When the inner ring of the bearing has a tight fit and the outer ring has a loose fit, place the copper rod close to the end face of the inner ring of the bearing, directly hit the copper rod with a hammer, and transfer the force through the copper rod to install the bearing on the shaft slowly.
When the inner ring of the bearing is large, you can use copper rods to strike hard evenly around the end surface of the inner ring of the bearing. Do not hit only one side, and do not use excessive force. Symmetrical tapping, gently tapping and slowly install it to avoid installing oblique cracking bearings .
▶▶ Installation with sleeve
This method is the same as using copper rods to install bearings. It is to press the sleeve directly on the end surface of the bearing (the end surface of the inner ring is pressed when the bearing is installed on the shaft; the end surface of the outer ring is pressed when installed in the housing hole), and the striking force of the hammer can be evenly distributed on the installation The whole bearing end face of the bearing can be used in conjunction with the press, saving labor and time, and reliable quality. The sleeve used for installation should be made of soft metal (either copper or low carbon steel pipe).
If the bearing is installed on the shaft, the inner diameter of the sleeve should be slightly larger than the journal 1-4mm, the outer diameter is slightly smaller than the diameter of the flange of the inner ring of the bearing, or the thickness of the sleeve shall prevail, and the thickness shall be made equal to the thickness of the inner ring of the bearing 2/3-4/5, and both ends of the sleeve should be flat and perpendicular to the barrel. If the bearing is installed in the seat hole, the sleeve outer diameter should be slightly smaller than the bearing outer diameter.
▶▶ Press-in method
The installation pressure should be directly applied to the end face of the interference fit bearing ring, otherwise it will cause pressure damage on the bearing working surface, causing the bearing to be quickly damaged.
▶▶ Heating installation
For the installation of bearings with large interference or large-size bearings, in order to facilitate installation, the principle of thermal expansion and contraction can be used, and the bearings are heated in the oil tank and then installed with copper rods, sleeves and hand hammers. The temperature during heating is generally controlled below 100°C, and 80-90°C is more suitable.
When the temperature is too high, it is easy to cause the bearing ring raceway and rolling body to anneal, affecting the hardness and wear resistance, resulting in reduced bearing life and premature scrap.
The fit between the bearing and the shaft is generally a transition fit, and the fit between the seat ring and the bearing seat hole is generally a clearance fit. The center shaft ring of the bidirectional bearing should be fixed on the shaft to prevent rotation relative to the shaft. Generally, the installation method of the bearing is that the shaft rotates most, so the fit between the inner ring and the shaft is an interference fit, and the fit between the outer ring of the bearing and the bearing chamber is a clearance fit.
When installing the bearing, you must first fix the dial indicator to the end surface of the box shell, so that the contact of the meter is on the bearing shaft ring raceway and rotate the bearing. While rotating, observe the pointer of the dial indicator. The axis centerline is not vertical. If the hole of the case is deep, it can also be inspected by the extended dial gauge. This is a good way to check the perpendicularity of the shaft ring and shaft centerline.
Bearing installation is reversed, not only does the bearing work abnormally, but also the mating surfaces will be severely worn. Since the difference between the shaft ring and the seat ring is not obvious, extreme care should be taken during assembly, and it cannot be reversed.
When the installation is correct, the seat ring can automatically adapt to the rolling of the rolling body to ensure that the rolling body is located in the upper and lower raceways. In addition, there should be a gap of 0.2-0.5mm between the bearing ring and the bearing seat hole to compensate for errors caused by inaccurate parts processing and installation. When the center of the bearing ring shifts during operation, This gap can ensure its automatic adjustment, avoid contact friction, and make it operate normally. Otherwise, it will cause severe damage to the bearing.
②Precautions during installation
1.For bearing rings with clearance fits, it is recommended to apply a thin layer of anti-creeping corrosion agent to the mating surfaces to prevent frictional corrosion between the mating surfaces.
2.The force applied to the bearing during installation must not be transferred from one bearing ring to another through the rolling element, otherwise it may cause damage to the raceway. However, under no circumstances should you directly strike the bearing rings, cages, rolling elements or seals.
3.Install an eccentric sleeve. First put the eccentric sleeve on the eccentric step of the bearing inner sleeve, and tighten it by hand in the direction of rotation of the shaft, and then insert or hold the small iron rod against the counterbore on the eccentric sleeve, and hit the small direction with the hammer in the direction of rotation of the shaft. Iron rod, make the eccentric sleeve installed firmly, and finally tighten the hexagon socket screws on the eccentric sleeve.
4.Do not tighten the bolts that secure the bearing housing first, but allow the bearing housing to rotate in the bearing housing. Then tighten the bearing seat bolts. Also install the other end bearing and seat on the same shaft, rotate the shaft a few times, and let the bearing itself find the correct position automatically.
5.Apply lubricating oil to the mating surfaces of the bearing housing and bearing, and install the bearing into the bearing housing. Then put the assembled bearing together with the bearing housing on the shaft and push it to the desired position for installation.
The correct installation of bearings can not only increase the service life of bearings, reduce costs, but also greatly improve production efficiency. Therefore, it is urgent to learn the correct bearing installation knowledge.
Products
- YRT rotary table bearing
- YRTS rotary table bearing (high speed series)
- YRTM with integral angular measuring system series
- ZKLDF axial angular contact ball bearing series
- RA series crossed roller bearing
- SX series crossed roller bearing
- CRBH series crossed roller bearing
- RE series crossed roller bearing
- RU series crossed roller bearing
- RB series crossed roller bearing
- XR/JXR series crossed taper roller bearing
- Crossed roller bearing
Contact Us
✉️ bearing20@hyzcgroup.com
📞 +86 15236685001
