Description
Cooper Pedestals for Bearings
Cooper Bearings are similar to self lube bearings, but you do not need to disassemble your machine to install or service them. Instead, Cooper components are split into two halves, which are then formed around the shaft and built up one piece at a time.
The advantage of such a system is that they can be installed, removed, serviced, partially or completely replaced without having to spend time dismantling your machine first. This design also allows for any misalignment to be taken up at the assembly stage.
Cooper bearings are divided into three sections: Bearings, Cartridges and Pedestals. The bearing is the rotating mechanical part, consisting of a roller cage with inner and outer races. The cartridge is the protective shroud around the bearing which contains the grease and seals. It also aids in mounting the bearing to the main housing. The Pedestal is the hollow block which is bolted to your machine. This keeps the cartridge and bearing at the correct position for the shaft to rotate.
Cooper bearings are commonly supplied in two forms: the Fixed Type (‘GR’) and Expansion Type (‘EX’) as described below. Where conditions are unsuitable for these standard types other configurations are possible.
Fixed Type Bearing (GR)
The outer race of the fixed (GR) bearing has shoulders integral with the roller track, while the inner race assembly has shoulders formed by hardened lips on the clamping rings or similar integral shoulders. This type of bearing provides axial location to the rotating portions of machinery and can sustain both radial and axial loading. The inner race halves are accurately aligned by means of fitted clamping rings.
Expansion Type Bearing (EX)
The expansion (EX) bearing has a plain outer race roller track. This bearing takes radial load only. The inner race is clamped to the shaft, and moves axially with it when expansion or contraction occurs. The Cooper expansion bearing offers virtually no resistance to axial movement as the rollers spiral through the outer race.
Pedestals
Pedestals (also known as Pillow Blocks) are the most common method of mounting Cooper split roller bearings. Pedestals are common between expansion (EX) and fixed (GR) units. Pedestals should be fully supported on a flat, rigid surface to avoid distortion of the pedestal or deflection under load. The flatness of the supporting surface should be to tolerance IT7 according to ISO 1101 and the surface roughness not more than 12.5µm Ra.
