Mounting bearings with a cylindrical bore
With separable bearings, the inner ring can be mounted independently of the outer ring, which simplifies mounting, particularly where both rings have an interference fit. When mounting the shaft and inner ring assembly into the housing containing the outer ring, careful alignment is required to avoid scoring the raceways and rolling elements. When mounting cylindrical or needle roller bearings with an inner ring without flanges or with a flange on one side only, a guiding sleeve should be used (fig. 1). The outside diameter of the sleeve should be the same as the raceway diameter of the inner ring and should be machined to tolerance class d10Ⓔ for cylindrical roller bearings, and to tolerance 0/–0,025 mm for needle roller bearings.
Safety precautions for fluoro rubber and Polytetrafluoroethylene
Fluoro rubber (FKM) and Polytetrafluoroethylene (PTFE) are very stable and harmless up to normal operating temperatures of 200 °C (390 °F). However, if exposed to temperatures above 300 °C (570 °F), such as fire or the open flame of a cutting torch, FKM and PTFE give off hazardous fumes. These fumes can be harmful if inhaled, as well as if they contact the eyes. In addition, once the seals have been heated to such temperatures, they are dangerous to handle even after they have cooled. Therefore, they should never come in contact with the skin.
If it is necessary to handle bearings with seals that have been subjected to high temperatures, such as when dismounting the bearing, the following safety precautions should be observed:
Always wear protective goggles, gloves and appropriate breathing apparatus.
Place all the remains of the seals in an airtight plastic container marked with a symbol for “material will etch”.
- Follow the safety precautions in the appropriate safety data sheet (SDS).
If there is contact with the seals, wash hands with soap and plenty of water and, if contact has been made with the eyes, flush eyes with plenty of water and consult a doctor immediately. If the fumes have been inhaled, consult a doctor immediately.
The user is responsible for the correct use of the product during its service life and its proper disposal. SKF takes no responsibility for the improper handling of FKM or PTFE, or for any injury resulting from their use.