Engineering - Steel bearings
Pivot bearing (PV), Pivot roller bearing(PVHR)
Fixed and movable bearings with pivot rotation
Pivot bearing are fixed bearing with a concave upper shoe and convex lower shoe, while extra-hardened pivot roller bearing are movable bearing that combine standard pivot bearing with multiple rollers. Both pivot bearing and pivot roller bearing are designed to track rotational movement in all directions.
Suitable for very large bridges subject to very large reaction force and movements
Pivot bearing have spherical upper and lower shoes to absorb vertical load and are designed to accommodate large reaction force. They are commonly used in very large bridges, particularly those of arch, truss and cable-stayed construction.
Extra-hardened pivot roller bearing are designed for much larger reaction force and movements, and employ a combination of pivots to support and track both vertical load and rotational displacement and rollers to track movement in the bridge direction. Pivot roller bearing are commonly used on larger bridges with medium to long spans.