Spherical plain bearings also known as “Ball Bushings”, “Spherical Plane bearings” and “Spherical ball bushing bearings” have been manufactured in a diverse category of materials and best suited to offer bearing solutions in most operating environment. They are normally available in sizes of inches and metric and are suitable for agricultural equipments, heavy duty machines, equipments in mining, construction and logging, robotics and off-highway vehicles.
Characteristics of Spherical plain bearings:
They have and inner ring comprising of spherical surfaces which is convex outside and an outer ring which has a concave surface inside and correspondingly spherical. This design makes them absolutely suitable for all bearing arrangements where slewing or oscillating movements should be permitted at slow sliding speeds.
Permissible Temperature for Operation:
In case of spherical plane bearing with seals, the operating temperature can vary from -20° +250°F. For spherical plane bearing without seals, the permissible range varies from -50° +300°F. The load capacity to carry will be low, when the temperature is high.
Bearing pillow block:
It is a mounting unit which is included with an anti- friction bearing to provide shaft support where the mounting surface is parallel to the shaft surface. The housing material used commonly would be cast iron or steel plate. Cast Iron, being used as a standard, provides greater performance while absorbing vibration and can withstand temperature up to 300°C In case of light-duty equipments or applications, these pillow block bearings are available with pressed steel.
Angular contact ball bearings:
These bearing have both inner and outer race rings that are placed at relative to one another in the same directing as the axis of the bearing. These types of bearings are best suited to support combined loads, which means, they simultaneously act in axial and radial directions. Higher the angle of contact higher is the axial load capacity and lower the capacity of radial load. Ceramics like Silicon nitride used in high speed equipments like dentistry, jet engines etc because of their low density which reduces the centrifugal force and functions better.
Maintenance and Maintenance-free:
Bearings with maintenance i.e., steel-on-steel are coated with a dry lubricant, which have hardened sliding surface of contact on both the rings with corrosion resistant and wear characteristics. The maintenance free spherical plain bearings will have sliding contact surface based on three types of groups. Steel-on-copper alloy, steel-on-PTFE material and steel-on-PTFE fabric. The friction here is very low and can be used for equipments where maintenance free long bearing lives are required and for operating conditions like inadequate lubrications or unavailability of lubrications.