FAG machine spindle bearing assembly

It must be ensured that the rolling contact surfaces have been adequately lubricated when the FAG machine spindle bearings are installed. The dimensional accuracy of adjacent structures must be checked. If you would like to obtain technical support during the initial installation, we recommend that you consult with an expert in industrial services, see page 146, chapter Equipment and services for rolling bearing installation and maintenance. Single-bearing solutions In a single-bearing solution, the compact design of the high-precision bearings YRTS and ZKLDF differs from that of the cross-roller bearings given in the TPI sample. High-precision bearings are consistent with the sample TPI 120, and high-precision bearings are installed in the sample TPI 103 (high-precision bearings subjected to combined loads). Cross-roller bearings Z-556 cross-roller bearings are supplied internally with a specific axial preload. For the cross roller bearing Z-549, axial preload is set during installation.


  When installing a double-bearing solution, it must be ensured on the one hand that radial deep groove ball bearings and angular contact ball bearings have good radial running. This can be achieved by centering the device or by aligning the axial retaining ring. On the other hand, axial preload must be set correctly by means of angular contact ball bearings. The three-bearing solution must ensure that the thrust deep groove ball bearings perform well in the radial direction relative to the radial cylindrical roller bearings. This can be achieved by centering or centering operations. Centripetal cylindrical roller bearings must be mounted with a specific radial preload, see Catalog SP 1, GMN Super Precision Bearings. Special attention must be paid to the preload of thrust bearings.
  Single bearing solutions Due to the size limitations of thrust/radial bearings YRTS and angular contact thrust ball bearings ZKLDF (see TPI 120, high-precision bearings subject to combined loads), cross-roller bearings are used here. The characteristics of these bearings are that the surrounding structure is simple, the design takes up less space, and the lubrication is convenient. The two-bearing solution uses two bearing configurations to meet the requirements of most applications. The main way of this kind of bearing configuration is a preloaded thrust bearing and another bearing, and the other bearing pretensions the thrust bearing and realizes a radial guiding function. This bearing solution can meet the high speed requirements. Angular contact ball bearings and tapered roller bearings can achieve this function. The three-bearing solution has a significant advantage in using a three-bearing arrangement where high accuracy and stiffness are required. However, the added workload due to installation must be considered.


  Single Bearing Solution Features In a single bearing solution, all loads are carried by a single bearing. This makes the surrounding structure of the bearing simple and compact. In addition, it is not necessary to center each bearing on one another, and lubrication is relatively simple because only one bearing needs to be lubricated. Cross roller bearings The rollers of these bearings are inclined relative to the shaft and the rollers are mounted in a continuous cross pattern. Separate the rollers with a plastic cage. The precision of these bearings is P5, and the running accuracy is better than P4. Cross roller bearings provide adjustable pretension or fixed pretension. High running accuracy In addition to the cross roller bearings described here, thrust/radial bearings YRTS and ZKLDF with diameters ranging from 200 mm to 460 mm are also suitable for these applications. Thrust/radial bearings ZKLDF can produce such bearings up to 1030 mm in diameter. These series of bearings have higher accuracy than THK crossed roller bearings. See TPI 120 for high precision bearings with combined loads.


  The solution characteristics of the two bearings Compared to the single bearing solution, the load on the two bearing solutions is shared by the two bearings. Thrust bearings mainly bear the weight of the table and the workpiece. Angular contact ball bearings are used to provide radial support while axially preloading the shafting. If thrust roller bearings are used, the system can withstand very high loads. For high speed applications, thrust ball bearings are recommended. During the design and installation process, it must be ensured that the minimum load can be satisfied under various load conditions. This also affects the recommended paired bearing configuration. Speed ​​In terms of speed, the use of ball bearing two-bearing solutions is a good choice for friction, lubrication and high precision. Accuracy dimensions and geometric tolerance accuracy are mainly determined by larger thrust bearings. The radial runout of the system is affected by the smaller diameter angular contact ball bearings.


  Solution Characteristics of Three Bearings In this arrangement, the combined loads are properly distributed to two thrust bearings and one radial bearing. This requires separate consideration of design requirements. The appropriate preload must be selected according to the load conditions to ensure the minimum axial load. Lubrication must be specially considered for lubrication. Although the thrust bearing needs more lubricating oil to dissipate heat, more oil is not necessary for a radial cylindrical roller bearing when the rotational speed is high. Depending on the design, radial bearings can, in most cases, be lubricated by smaller thrust bearings above, see page 124. Rigidity The high rigidity of the bearing system can be achieved by a fixed axial preload between the two thrust bearings and radial pretensioning of the radial bearings, typically up to 5 μm radial pretensioning, see section 126 Page and sample SP1, super precision bearings. Accuracy Dimensions and Geometrical Tolerances If each bearing is accurately combined, this bearing configuration can achieve very high accuracy.