When designing a new spindle, before selecting an INA bearing, first consider the spindle performance parameters, roughly determine the most critical performance, and then enter further exploration. (Including: spindle speed, spindle accuracy, spindle rigidity, spindle life, spindle heat, spindle reliability) After the spindle parameters are determined, the actual dimensions of the spindle (shaft diameter, length, bearing span) are determined. ERIC BEARING LTD have rich stock for INA SL045006-PP- 2NR, pls click here :
According to the bearing type (ball or cylindrical roller bearing), arrangement (column number), drive mode (transmission belt, gear, motor, built-in motor), lubrication (grease, oil and gas, oil mist, spray) and other spindle parameter settings Its structure.
Bearing radial load
The INA bearings that mainly bear radial loads are radial bearings. The nominal contact angle of this type of bearing a0 <= 450. Roller bearings with the same ruler can bear larger radial loads than ball bearings.
N-type and NU-type cylindrical roller bearings can only bear radial loads, and other types of radial bearings can bear both radial loads and axial loads.
Bearing axial load
The bearings that mainly bear axial loads are generally thrust bearings, whose nominal contact angle a0> 450. Thrust bearings and thrust angular contact ball bearings can withstand axial forces in one or two directions at the same time, depending on the structure. When the bearing force is particularly high, thrust cylindrical roller bearings and thrust spherical roller bearings are preferred.Thrust spherical roller bearings and one-way thrust angular contact ball bearings can withstand both axial and radial loads, and other thrust bearings can only withstand axial loads.
Bearing length compensation
Supporting a shaft and a bearing usually adopts a structure in which a fixed bearing and a floating bearing are combined. Traveling INA bearings compensate for shaft length errors and thermal expansion.NU type and N type cylindrical roller bearings are ideal free bearings. These bearings can compensate for their own length. The inner and outer rings of the bearing can be tightly fitted.
Length compensation for sliding fit
Non-separable bearings can also be used as swimming bearings. One of the two rings of this type of bearing adopts a fit, and there is no axial fixed surface. Therefore, a ring of the bearing can move on its bearing surface.After determining the size and type of precision bearings, consider the specific design of the bearings.
Fully consider the bearing fatigue life, rigidity, heat and other factors, select the most appropriate bearing clearance (preload).After determining the design of the main shaft structure, the necessary conditions for actual installation should be considered.
High-precision bearing installation shaft and bearing seat accuracy, tolerance fit, tightening force of set nut required for installation and fixing, INA bearing preload after actual installation and confirmation of internal clearance.INA bearings are precision fittings, and need to be handled according to the correct method during installation and use in order to extend the service life of INA bearings. ERIC BEARING LTD have rich stock for INA NUTR50-A, pls click here :
The surface of the INA bearing is coated with anti-rust oil. You must carefully clean it with clean gasoline or kerosene, and then apply clean high-quality or high-speed high-temperature lubricating grease before installation and use. The effect of cleanliness on the life of miniature bearings and vibration noise is very large. But we have to remind you in particular that the fully enclosed bearings do not need to be cleaned and refueled.
When lubricating INA bearings, the more grease is applied, the better. This is a common misconception.
The correct installation of INA bearings also affects the accuracy, life, and performance of the bearings. Therefore, the design and assembly department should fully study the installation of INA bearings. Hope to install according to the operation standard. The work standard items are usually as follows:
(1) Cleaning bearings and bearing related parts
(2) Check the dimensions and finishing of related parts
(4) Inspection after installing the bearing
(5) Supply lubricant
During use, the basic external conditions of INA bearing operation must be monitored frequently, such as temperature, vibration and noise measurements. These regular inspections will detect potential problems early and will prevent unexpected machine stoppages, enable production planning to be realized, and increase plant productivity and efficiency.
During operation, INA bearings require correct relubrication to perfect its performance. When the bearing will reach its end-use period, it should be replaced.Although the INA bearing can no longer be used, but the original bearing is properly removed, and the new bearing is replaced in time, which can promote the service life of the new bearing.
During the installation of imported INA bearings, many users responded that the INA bearings themselves can achieve the required accuracy, but after the installation, they cannot reach the accuracy. Shanghai Shaanyan trade engineers will share with you the methods to improve the installation accuracy of INA imported bearings.
The engineer explained that the main reason for the insufficient accuracy of the INA bearing after installation may be that we cannot guarantee whether the temperature value of the heated area of the INA bearing is uniform during the heating process. If the temperature is too high, the INA bearing will be annealed and reduce the INA bearing's Mechanical properties; temperature is too low, thermal expansion value is not enough, it is difficult to assemble .In order to solve this problem, we propose a new method to change the traditional assembly of INA bearing heating
Use electric heating instead of acetylene oxygen heating
The flat electric furnace is designed as a cylindrical electric furnace, named INA bearing electric heater. According to different INA bearing inner diameter, it can be designed into INA bearing electric heater with different power and specifications (the best applicable range is INA bearing inner diameter φ300mm / the above). This heating device has the following advantages: uniform and stable heat radiation, no smoke and dust on the surface of the heated INA bearing, clean and clean, easy to measure and control the temperature of the INA bearing.
Infrared thermometer for its warm
INA bearing surface temperature monitoring. The heating value of INA bearing assembly is generally controlled at 100 ℃ ～ 120 ℃. Within this temperature value, the INA bearing steel has the largest thermal expansion value, which is convenient for INA bearing assembly. This temperature value will not change the mechanical properties of the INA bearing and has high reliability.
In summary, the INA bearing electric heater is superior to the traditional acetylene oxygen heating, and is an effective method to improve the INA bearing assembly accuracy and working efficiency and reduce labor intensity.
INA imported bearing precision improvement method
After the INA bearing is installed in the host, if the radial run out of the main shaft is measured, it can be found that the measured value of each revolution has a certain change; when continuous measurement is performed, it can be found that after a certain number of revolutions, this change will be approximately Repeatedly. The index to measure the degree of this change is the cyclic rotation accuracy. The number of revolutions required for the change to reappear approximately represents the "quasi-period" of the cyclic rotation accuracy. The magnitude of the change in the quasi-period is large, which is the cyclic rotation accuracy. If the spindle is properly preloaded, the speed will be gradually reduced to close to the compulsory speed to implement the "run-in" effect of the INA bearing, which can improve the cycle rotation accuracy of the spindle .