Key steps and detailed instructions installing bearings
Source:NETAuthor:UN Addtime:2022-05-16 Click:
Whether the joint bearing is installed well or not will affect the accuracy, life and performance of the joint bearing. Therefore, please fully study the installation of the spherical plain bearing, that is, please follow the steps including the following items to install the spherical plain bearing.
(1) Cleaning of spherical plain bearings and related parts
For grease-lubricated spherical plain bearings and oil seals or dust caps on both sides, the sealing ring spherical plain bearings do not need to be cleaned before installation.
(2) Check the size and finishing of the relevant parts
(3) Installation method
The installation of the spherical plain bearing should be determined according to the structure of the spherical plain bearing, the size and the matching nature of the spherical plain bearing parts. The pressure should be directly applied to the end face of the tight fitting ring, and the pressure should not be transmitted through the rolling elements. The spherical plain bearing installation generally adopts the following methods:
A. Press fit
When the inner ring of the spherical plain bearing is tightly fitted with the shaft, and the outer ring and the spherical bearing seat hole are loosely fitted, the spherical plain bearing can be press-fitted on the shaft by a press, and then the shaft together with the spherical plain bearing is installed into the spherical bearing seat hole. , When press-fitting, on the end face of the inner ring of the spherical plain bearing, pad an assembly sleeve (copper or mild steel) made of soft metal material. The inner diameter of the assembly sleeve should be slightly larger than the diameter of the journal, and the outer diameter should be larger than the inner diameter of the spherical plain bearing. The ring ribs are slightly smaller to avoid pressing on the cage. The outer ring of the spherical plain bearing is tightly fitted with the hole of the spherical plain bearing seat, and when the inner ring and the shaft are loosely fitted, the spherical plain bearing can be pressed into the hole of the spherical plain bearing seat first. At this time, the outer diameter of the assembly sleeve should be slightly smaller than the diameter of the seat hole. If the spherical plain bearing ring is tightly fitted with the shaft and the seat hole, the inner ring and the outer ring should be pressed into the shaft and the seat hole at the same time. .
B. Heat fit
It is a common and labor-saving installation method to convert the tight fit into a loose fit by heating the spherical plain bearing or the spherical plain bearing seat by thermal expansion. This method is suitable for the installation of spherical plain bearings with large interference. Before hot-loading, put the spherical plain bearing or the ferrule of the separable spherical plain bearing into the oil tank and evenly heat it at 80-100 °C, then take it out of the oil and install it on the shaft as soon as possible. In order to prevent the inner ring end face and the shaft shoulder from not fitting tightly after cooling, the joint bearing can be axially tightened after cooling. When the outer ring of the spherical plain bearing is tightly fitted with the spherical plain bearing seat made of light metal, the hot-fitting method of heating the spherical plain bearing seat can be used to avoid the mating surface from being scratched. When heating the joint bearing with the oil tank, there should be a mesh grid at a certain distance from the bottom of the box, or hang the joint bearing with a hook. The joint bearing cannot be placed on the bottom of the box to prevent heavy impurities from entering the joint bearing or uneven heating. There must be a thermometer, and the oil temperature should not exceed 100 ℃ strictly to prevent the tempering effect and reduce the hardness of the ferrule.
C. Installation of tapered bore spherical plain bearings
The tapered bore bearing can be directly mounted on the tapered journal, or on the tapered surface of the adapter sleeve and the withdrawal sleeve. The tightness of the fit can be measured by the reduction in the radial clearance of the spherical plain bearing. Therefore, before installation The radial clearance of the spherical plain bearing should be measured. During the installation process, the clearance should be measured frequently to achieve the required clearance reduction. Generally, the lock nut is used for installation, and the heating installation method can also be used.
D. Installation of thrust spherical plain bearings
The match between the shaft washer and the shaft of the thrust bearing is generally a transition fit, and the match between the seat washer and the joint bearing seat hole is generally a clearance fit, so this kind of joint bearing is easier to install, and the central axis of the two-way thrust joint bearing should be fixed on the shaft. , to prevent rotation relative to the shaft. The installation method of the spherical plain bearing is generally the case where the shaft rotates, so the fit between the inner ring and the shaft is an interference fit, and the fit between the outer ring of the spherical plain bearing and the spherical plain bearing chamber is a clearance fit.