Adapter and removal sleeves serve to mount and remove bearings with tapered bores onto cylindrical shafts. They are commonly used to compensate for a size deviation between the bearing bore and shaft diameter or to convert sizes from metric to inch. Both adapter and removal sleeves utilize lock nuts to hold the bearing in position after being mounted on the sleeve. Adapter sleeves are more common than withdrawal sleeves and can be used on a smooth or stepped shaft. Threads located on the small end of the tapered sleeve are used in conjunction with a nut to push the bearing up the tapered surface. This allows the bearing and sleeve to seat firmly in place. In contrast, a removal sleeve has threads located on the large end of the taper. Mounting is facilitated by threads located on the shaft and by a shaft abutment. The bearing seats against the abutment as a nut pushes the removal sleeve into the bore of the bearing. Dismounting is eased by the use of a second nut located on the large end of the sleeve. However, the best way to remove a bearing from an adapter or withdrawal sleeve is by hydraulic oil holes. Removal with hydraulic oil both eases removal and prevents serious damage on the bearing. A hydraulic nut can also be used to accurately position a bearing up the taper of a sleeve.
Lock nuts are torque fasteners that are often used when mounting a bearing. Internal threads allow the lock nut to connect to adapter or removal sleeves as well as threaded shafts. This makes it possible to adjust and maintain the bearing position as well as facilitate bearing removal. Lock nuts can utilize lock washers to prevent the nut from backing off. Grooves on the outer peripheral of the nut allow for tightening by a spanner wrench.
Lock washers are utilized to secure lock nuts. A tab washer is the most common type used in industry. Tab washers contain an internal tab which fits into a shaft keyway. The washer also contains external tabs that fit into slots located on a lock nut. When the lock nut is fully tightened, and the internal tab is properly positioned, one of the external tabs on the washer is bent over into one of the locknut slots. This prevents the locknut from backing off as the shaft rotates.
Hydraulic nuts are intended to ease mounting of large bearings. Often the forces required to seat a bearing properly on an adapter or removal sleeve can be quite large and difficult to achieve if done by hand. Hydraulic nuts are able to provide constant pressure to seat the bearing with very little resistance. The hydraulic nut is threaded onto the shaft or sleeve and provides the force required to move the bearing up the taper of the sleeve. After the bearing is properly positioned, the hydraulic nut may be removed and a lock nut is utilized to secure the bearing in place. Hydraulic nuts facilitate mounting and dismounting when moving the bearing proves to be an issue.
Labyrinth seals utilize a sequence of metal rings to prevent contamination and lubrication leaks. These metal rings do not touch, but rather, create a labyrinth of gaps, which prohibits substances from penetrating the seal. Labyrinth seals maintain low friction by avoiding ring contact. Low friction enables the seal to operate at high temperatures, withstand high rotational velocity, and extend service of the bearing. Applications include gas turbines, tool machining, and centrifugal compressors.
A plummer block is a housing unit where the bearing is purchased separately. In general, a plumber block housing is intended for larger loads than a pillow block and often the bearing is fitted onsite. The housing is typically split, allowing the bearing to be properly seated in the housing and removed when needed. Standard plummer blocks are made of grey cast iron, although other materials are available. Plummer blocks contain two or four bolt holes that hold the housing firmly in place. Seals are also available to bar contamination from entering the plummer block housing.
Stabilizing rings are intended to inhibit axial movement of a bearing. The rings, located between the housing and the outer race of the bearing, fix the bearing position and disallow shaft expansion. Stabilizing rings should only be used to fix one bearing per shaft. The other bearings must be allowed some degree of positional freedom.
Lubrication systems automate the process by which lubricant is dispersed into a mechanical structure. These automated systems remove the need for manual lubrication, which may be difficult and tedious. Programmed settings ensure that the optimal amount of lubricant is given at set intervals. As a result, performance is enhanced and premature failure is avoided. Systems vary depending on parameters such as volume capacity, maximum temperature, maximum pressure, and distribution rate. Applications include cables, dies, air lines, and pumps.
- Hydraulic Nut
- Lock Nut
- Lock Washer
- Lubrication System
- Plummer Block
- Removal Sleeve
- Seal Ring
- Stabilizing Ring