LCL's Spherical Bearings have been designed to
be very easy to install, maintenance-free and cost-effective. The
product has been successfully used in a broad range of applications
which include: vehicle bridges, railway bridges and stadiums.
LCL's Spherical Bearings are designed for very high vertical, horizontal
and lateral loads and where large rotational structural displacements
need to be accommodated. The bearings are grouped into three categories:
fixed bearing (restriction of all movement in planar axis); guided
bearing (restriction of movement in one direction in planar axis);
multi-directional bearing (allows movement in all planes and axes).
All three types can be designed to accommodate uplift loads, often
required during construction or during the life of the structure.
The bearings are designed to be quickly and easily replaced because
of the structural fastening and attachment strategy LCL deploys.
Structural rotation is accommodated by a system of convex and concave
plates which are, in turn, mounted onto a flat sliding surface which
allows horizontal displacements whilst the curved bearings rotate
about their center of radius. In addition the bearings have the
capability to rotate in any direction (constraint-free rotation)
around both horizontal and vertical planes by the sliding action
of the curved spherical surfaces. The spherical bearings are capable
of large tilting angles with very low tilting resistance. LCL offers
two spherical bearing products which differ mainly in accordance
with the strategy used at the sliding surface interface.
The most popular product is designed primarily for use in railway
bridges and consists of a convex bronze or stainless steel base
plate which is self lubricating through the incorporation of trepanned
recessed reservoirs containing solid lubricants whose primary constituent
is molybdenum. The concave smooth finished steel top plate slides
over the base plate which allows the large rotational displacements.
However, by adopting an advanced materials design approach, LCL
also offers a Spherical Bearing which consists of a convex aluminium
or stainless steel base plate but where the steel top plate is machined
to accommodate a dimpled Teflon (PTFE) sheet. In this way the PTFE
sheet is mechanically recessed and confined, resulting in superior
mechanical binding. Compared to the traditional method of surface
bonding the sheet, LCL's design approach guarantees the integrity
of the sliding surface components during the life time of the bearing.
All of LCL-Bridge Spherical Bearing designs, materials & fabrication
processes can be adapted to client required manufacturing specifications
or codes of practice; for any Country. The bearing is designed to
be maintenance free for the duration of its design life and can
operate down to extremely low temperatures; as low as - 40 degrees