Ložiskové jednotky NTN-SNR

SNR Industry 33 In order to prevent possible damage to the bearing insert due to improper assembly, the housing must first be screwed down onto its respective base or onto the frame before the inner rings of the inserts are tightened into their final position on the shaft. Otherwise, undesirable axial distortion could result and thus premature failure of the bearing. The ends of the shaft should be provided with a chamfer for easier assembly. It must be ensured that the set screws of the bearing inserts are screwed out far enough so that they do not project in the inner ring bore. Otherwise, assembly can be difficult or the shaft could even be damaged. Normally the bearing inner rings are slid onto the shaft with a tight loose fit. If for individual cases an inter- ference fit proves to be essential, the inner rings should be fit using a suitable piece of pipe, preferably made of brass or plastic. We also supply the respective assembly tools for all bearing inserts, as well as for standard bearings. Direct hammer impacts on the inserts or the housing must be avoided because they can damage the bearing. When assembly is finished, the shaft is initially turned by hand in order to ensure rotation without problems. In operation, cast iron housings should be stressed by pressure force and not by tension, if possible. Take-up units must be positioned in that way, that the straining screw presses against the housing during adjustment. Grey cast iron housings are not suitable for highly alternating or axial dynamic loads. In such cases, housings made of cast steel or nodular graphite iron should be used. Mountings with large bearing spread and bearings which are exposed to additional axial loads because of highly variable temperatures, require special measures, such as mounting a floating bearing screw. Additional information about assembly Securing the housing If exact positioning of the bearing unit is required, some of the housing types can be secured using available centring, or straight or tapered pins. Housing types with possible positions of the pin bores can be found in the tables starting on page 190.