Technical information

Cleaning operations
Empty and clean out mixing drum with
plenty of water.
Clean out hopper.
Drain water tank if frost is likely.
Raise hopper and fix safety chain. Stop
engine or electric motor. Wash down
outside of mixer.
Grease up machine for next day's work.
Keep the mixer clean.
Hose Failure Valve
Machines bearing the "CE" mark
indicating compliance with the EC
Machinery Safety Directive have a Hose
Failure Valve fitted to the ram inletl/outlet
port in addition to the restrictor.
In service it is not unusual for violent
operation of the control valve (in order to
shake material free from the hopper when
the ram is at the full extent of its stroke) to
blow off the relief valve activating the
Hose Failure Valve, which then prevents
closing of the ram and lowering of the
hopper.
Should this occur, slowly lift the hopper
slightly by extending the ram without
blowing off the relief valve, then slowly
close the ram lowering the hopper. Once
the hopper has lowered by approximately
300mm normal operation can be
resumed.
If a new hose failure valve is to be fitted
the valve should first be unscrewed from
the body, and the gap between the valve
baffles adjusted to 2mm by means of the
small capscrew and nut. Following
adjustment, the valve should be screwed
fully home into the body and operation of
the machine checked when it is fitted.
Hopper Ram
The hydraulic cylinder/ram is single acting
and certain climatic conditions can cause
the formation of condensation in the
cylinder bore when the hopper is left
lowered when the mixer is not working.
This will lead to corrosion which will
damage the ram, seals and bore surface.
If the ambient temperature is expected to
fluctuate considerably or the mixer is not
to be used for sometime fully raise the
hopper, attach the safety chain leaving the
hopper in the raised position. As the
cylinder is full of oil this will help prevent
the formation of condensation.
When lowering the hopper; first fully raise
the hopper, unhook the safety chain and
slowly lower the hopper.
Over long periods oil will leak back into
the tank and it is prudent to
raise/lower/raise the hopper to re-charge
the cylinder with oil.
Over long periods carry out the above
procedure on a weekly basis to ensure the
internal surfaces are coated with oil.
NOTE: From April 2000, the annulus side
of the hopper ram is connected to
a header tank to ensure that the
ram cylinder is always full of oil.
This will prevent condensation
from forming within the cylinder.
(See Parts page E-1E.)
OPERATION 2.13