Bearing retention / Securing Bushes
A Vesconite bearing can be retained in a number of ways:
Interference fitting
Mechanical securing
Adhesive bonding

As a safety precaution, bearings may be secured using conventional mechanical means such as keeper rings, key ways and grub screws. Interference fitting This is when the outside diameter of the bearing is slightly larger than the housing into which it fits. This is the most common method of retention. This method of installation is suitable for applications across a standard temperature range. In sub-zero conditions, it is usually advised to use interference fitting with mechanical securing.

The bearing is then installed by press or freeze fitting. Bearing sizes are calculated for Vesconite for metric, imperial and marine applications.

Mechanical securing
If the application requires that interference fitting is not suitable due to high temperatures or installation limitations, mechanical securing ensures that the bearing remains in its housing.
To prevent possible rotation, keeper rings, keeper plates or grub screws are used. This is especially important for bearings that may be used in sub-zero conditions and is often done together with interference fitting.
When using grub screws, take care that minimal pressure is applied to the bearing. Drilling recessed holes are often required.
Mechanical securing of a split bearing can be done using grub screws.

Adhesive bonding
If desired, anaerobic adhesives such as Loctite 603 or 648 retaining compound may be used. Epoxy suitable for plastics may also be used. Adhesive bonding is recommended when using sliding fits.

Machine a lead in chamfer of 15° to 35° on the leading edge of the bearing to ease the installation. Roughen the steel surface and the Vesconite to aid the bonding.

The bearing should be pressed into place and excess adhesive wiped off.

To improve bonding, the Vesconite surface may be lightly roughened.

Updated Jun 01  2005