1.Selection and requirements of the installation site
The installation site should be at a distance from lathes, grinders and other mechanical equipment. The site should be cleaned, kept dry and clean, and strictly prevent iron filings, sand particles, dust, and moisture from entering the bearing.
2.Check bearing model and prepare installation tools
Check whether the IKO bearing model and size meet the installation requirements, and select the appropriate assembly method according to the structural characteristics of the non-standard bearings and the various components matched with it, and prepare the tools and measuring tools for installation. Commonly used installation tools include hand hammers, copper rods, sleeves, special backing plates, snail mosquito fixtures, presses, etc., with vernier calipers, micrometers, dial gauges, etc.
3.Inspection of bearing assembly surface
If there are bruises, rust, abrasive debris, sand, dust, and dirt on the assembly surface of the IKO bearing assembly and the parts that cooperate with it, one bearing is difficult to install, resulting in an incorrect assembly position; second, these attachments form abrasive It is easy to damage the working surface of non-standard bearings and affect the quality of assembly.
Therefore, before installation, the mating surfaces of the journal, bearing housing hole surface, shoulder end surface, and connecting parts such as bushings, washers, ends, etc., should be carefully inspected. If there is a rust layer, you can use a fine file to file it off and polish it with a fine emery cloth. At the same time, the attachments on the bearing assembly surface and its connecting parts should also be removed.
For IKO bearings with separable inner and outer rings, do not interchange the outer rings so as not to affect the contact quality. For non-standard bearings, the rolling elements in the bearings must not be taken out and placed arbitrarily, so as to avoid the installation position disorder and affect the accuracy. IKO CRWU 40-50 runner block ,ERIC BEARING LTD can supply , pls refer to below photos :
When installing IKO bearings, in order to facilitate the inspection of the bearing code and not cause errors, the typing side of the bearing ring should be placed and installed outward.
4.Heating of bearing and housing shell hole
For medium and large bearings with large interference, it is necessary to heat them before installation in order to facilitate installation; for tightly fitting light metal housing shell holes (such as aluminum housing), due to the low hardness, in order to prevent IKO bearing outer ring pressure The surface of the housing hole of the bearing seat is scratched or roughened when entering, and it should also be heated.
The heating method is generally to place the bearing or separate bearing ring in the oil tank filled with clean engine oil, so that the engine oil floods the non-standard bearings and heats up evenly.
When the temperature reaches 80-90℃, take it out and clean it, and install it while it is hot. The oil tank can be made of 2-3mm thick iron plate, a porous iron plate is added at a height of 50-70mm from the bottom of the tank, and the bearing is placed on the porous iron plate for heating. The purpose is to avoid the precipitation of impurities in the oil into the bearing.
However, for bearings with dust caps or seals on both sides, since lubricants have been added to the manufacturing, they cannot be heated at the early stage of installation.
5.Matching selection of rolling bearings
(1)Choose the basis of cooperation
According to the rotation of the load acting on the bearing relative to the ring, there are three types of load on the IKO bearing ring: local load, cyclic load and swing load. Generally, cyclic load (rotating load) and swing load adopt tight fit; except for special requirements on the use of local load, tight fit is generally not suitable.
When the non-standard bearing ring bears the dynamic load and is heavily loaded, the inner and outer rings should use an interference fit, but sometimes the outer ring can be a little loose, and it should be able to make axial movement in the housing hole of the bearing housing ; When the bearing ring bears oscillating load and the load is light, you can use a looser fit than the tight fit.
The interference between the IKO bearing ring and the shaft or housing hole depends on the size of the load. When the load is heavier, a larger interference fit is used; when the load is lighter, a smaller interference fit is used. Generally, the radial load P is less than 0.07C for light load, P is greater than 0.07C and equal to or less than 0.15C is normal load, and P is greater than 0.15C for heavy load (C is the rated dynamic load of the bearing)
The necessary secrets for the selection of IKO rolling bearings
IKO bearings with relatively low noise
When the above two types of low noise bearings cannot be used, bearings with relatively low noise can be used. The specific comparison basis is as follows:
(1)The noise of the ball bearing is lower than that of the roller bearing, and the (friction) noise of the bearing that slides relatively less is lower than that of the bearing that slides more; the more the number of balls, the thicker the outer ring, the smaller the noise;
(2)The noise of bearings using solid cages is relatively lower than that of bearings using stamped cages;
(3)The noise of bearings using plastic cages is lower than that of bearings using the above two cages;
(4)High-precision bearings, especially those with higher rolling element accuracy, have relatively less noise than low-precision bearings;
(5)The noise of small bearings is relatively smaller than that of large bearings.
Vibration can be said to be quite sensitive to damage to IKO bearings, and flaking, indentation, rust, cracks, wear, etc. will be reflected in bearing vibration measurements.
Therefore, the size of the vibration can be measured by using a special IKO bearing vibration measuring instrument (frequency analyzer, etc.), and the specific circumstances of the abnormality cannot be inferred from the frequency points. The measured value differs depending on the use condition of the bearing or the installation position of the sensor, etc. Therefore, it is necessary to analyze and compare the measured value of each machine in advance to determine the judgment standard.
Scar sound and its control method If the rolling surface of the rolling bearing has cracks, indentation or corrosion, periodic vibration and noise like riveted rivets will occur. The period may be fixed but most of them have a certain corresponding relationship with the speed. It will occur continuously on the channel, and the scars will appear on the steel ball from time to time, and this noise will have certain changes with the installation and lubrication conditions.
The control methods of this type of noise are: do not knock on the IKO bearing during installation, prevent the bearing from slanting when the bearing is assembled with the shaft and then install it in the bearing housing; prevent corrosion of the IKO bearing in stock and prevent impact vibration during transportation; high viscosity Of grease.