
11
CASTOR SAFETY & MAINTENANCE
CASTOR SAFETY & MAINTENANCE
In order to ensure the Nano castors are maintained in serviceable and
safe condition, regular inspection is required, especially where arduous
conditions are known to be involved or there is a suspicion of misuse or
abuse. The other key element to ensure is in safe serviceable condition, is
the castor xing bolt, the condition of which can usually be determined
from the condition of the castor bracket.
The castor is highly rated for the application so if visible distortion is
evident a signicant impact will have occurred and under these conditions
the castor and xing must be replaced.
Typical signs of impact which would require castor and xing replacement:
It may be thought feasible to repair the castor in a number of these
instances, but serious structural damage will have occurred to the head
bearing and castor assembly as well as possibly damage to the main
mounting bolt.
When inspecting a castor in order to
determine its serviceability, pay particular
attention to the head swivel bearing
(compare to a new one if possible) and the
boss/rivet which goes through the centre
of the swivel bearing and which clamps the
assembly together.
If the castor is in sound condition,
free from distortion then it may be adequate
to only replace the main xing bolt
with one of a higher tensile
strength, along with a spacer
washer that enables a higher
bolting torque to be applied.
This will improve the reliability of
the x, but will not increase the
strength of the castor assembly.
The new xing nut and bolt are
to be re-torqued to 55Nm.
In order to replace the xing bolt,
the wheel axle bolt, half nut and star washer will rst
need to be removed, along with the central bushing
tube and M12 end washers. This enables the wheel
to be removed so that the castor xing bolt can be
replaced.
When retting the wheel, the axle bolt, half nut
and star washer, must be replaced with OEM
specication new parts and re-torqued to 80Nm
(Pic A). Ensure the axle tube and assembly is lightly greased to ensure a
smooth action when operating the foot brake.
Power Towers Limited strongly recommends replacing any castor
assembly that is over 3 years old with a new one.
Swivel bearing head
should feel free to rotate
and not loose
Castor mounting bolt
Side impact and foot
pedal distortion as a
result of a signicant side
impact.
Top mounting plate distortion as a
result of a single signicant impact
or multiple lower level impacts.
Even if the rest of the castor is
in good condition, it must be
replaced.
Foot pedal distortion as a result
of a signicant frontal impact; it is
likely the top plate and bearing will
be distorted as well.
M12 nyloc nut torque
to 55Nm.
M12 standard washer.
Special thin spacer
washer on top of swivel
bearing of castor
M12X60 10.9 bolt
Pic A.
Important.
These instructions apply to all Nano machines BEFORE
serial no. 26953115C
Courtesy of Crane.Market