Characteristics and Application of Thrust Bearings in Printing Machines1

Product overviewPrinting machine thrust bearing thrust cylindrical roller bearing ZARA ZARI0001837E0001837A thrust needle roller bearing ZAXA00018380 angular contact ball bearing single row 72..-BE-2RS00018675 thrust angular contact ball bearing ZKLF...-2RS. The characteristics of the thrust bearing of the printing press are arranged in conjunction with the floating bearing, and the thrust bearing is used to provide axial support for the main cylinder. Capable of bearing bi-directional loads, usually with zero clearance. According to the requirements of the printing press, thrust cylindrical roller bearings, thrust needle roller bearings or angular contact ball bearings can be selected. Additional information ■ For more detailed information see catalogue HR 1, Rolling Bearings, Axial Cylindrical Roller Bearings, Axial Needle Roller Bearings Or internally centred intermediate washers ZS, Fig. 1. The seat washer can be centered externally and the shaft washer can be centered internally. Depending on the design, they can have a relative radial displacement s, see dimension table. The shaft and race outer surfaces are ground. Preload In some applications, ready-to-install bearing units with pre-adjusted inner rings are available. Bearing units designed with pre-adjusted inner rings are free of play. Applications Thrust bearings are particularly suitable for bearing axial forces in main roller bearing arrangements. They are extremely rigid in the axial direction and can only withstand axial forces in both directions. Angular contact ball bearings Single row angular contact ball bearings to DIN 628-1 are available in open and sealed designs, Figure 2. Universal mating designs have the suffix UL or UO and can be arranged in either an X or O arrangement, see table on page 104. Preload In printing machinery, angular contact ball bearings are usually designed with zero clearance or light preload, preferably angular contact ball bearings of the 72..-B series. Radial and axial load capacity Single row angular contact ball bearings can withstand unidirectional axial force and large radial force. Axial adjustment requires another bearing mounted symmetrically with it. The axial load carrying capacity depends on the contact angle. That is, the larger the contact angle, the larger the axial load that the bearing can bear. Due to their 40 contact angle, these bearings can withstand high axial loads. Application-matched single-row angular contact ball bearings are particularly suitable for use as thrust bearings in printing press main cylinders due to their low friction and high axial stiffness. Thrust angular contact ball bearing ZKLF thrust angular contact ball bearing is a self-retaining structure, double row angular contact ball bearing contact angle 60 into an O-shaped arrangement, Figure 3. The inner ring is adjustable to guarantee zero play. A contact angle of 60 guarantees high axial stiffness. The thick-walled outer ring allows it to be bolted directly to adjacent structures. Makes installation extremely easy. Axial angular contact ball bearings are high precision bearings: ■ Integral thick-walled outer ring with lubrication holes and mounting holes ■ Double inner ring with ball and cage assembly ■ Lip seal or gap seal. Figure 3 Two-way thrust angular contact ball bearing. Printing Press Thrust Bearing Seals Printing press thrust bearings can be sealed by seals mounted to the adjacent structure, or angular contact ball bearings with the suffix 2RS, with lip seals on both sides. RS contact seals are used to prevent the ingress of dust, contaminants and water vapour. Lubrication In some cases, thrust cylindrical roller bearings and thrust needle roller bearings can be relubricated through the inner ring or intermediate washer. Angular contact ball bearings or thrust angular contact ball bearings with lip seals on both sides are filled with high-quality grease and lubricated for life. In some applications, relubrication is required. In this case, Arcanol MULTITOP greases are suitable. Suffix Suffixes for existing designs: see table below. Existing design suffixes describe design UL universal matching bearings, bearing pairs in O or X arrangements with light preload Standard design UO universal matching bearings, bearing pairs in O or X arrangements with zero clearance. Design and Safety Guidelines Adjacent Part Design The entire face of the thrust bearing washer must be fully supported. Adjacent shoulders must be rigid, flat and perpendicular to the axis of rotation. Geometrical tolerances for precision thrust bearings DIN 620-3 (ISO 199), see page 28.