4.5
Securing rims
The NAV 11-21-31, B956, B957 and R926 series tyre-changers are equipped with an oil pressure adjuster, for the
oil contained in the hydraulic system.
The pressure is indicated on the pressure gauge. With weak or especially thin rims, it is advisable to reduce
pressure; with especially thick and hard to remove rims, hydraulic pressure should be set on maximum.
For alloy rims, it is necessary to use low hydraulic pressures and fit special tools on the chucking table to avoid
damaging the rim.
ADJUSTING THE PRESSURE ALSO ADJUSTS THE CLAMPING FORCE OF THE CHUCKING TABLE.
THE VALVE IS PRE-SET TO OPTIMUM PRESSURE FOR SECURING THE RIM'S FLANGE FROM THE
INSIDE (SEE "TECHNICAL SPECIFICATIONS"). WHEN SECURING DIRECTLY ON THE INSIDE OF
THE METAL SHEET OR ON ALLOY RIMS, IT IS ADVISABLE TO REDUCE THE PRESSURE SO AS
NOT TO BUCKLE OR DAMAGE THE RIM ITSELF. BE VERY CAREFUL WHEN REDUCING THE
FORCE OF THE GRIPPERS, TO AVOID RIM UNCLAMPING DURING TYRE FITTING/REMOVING DUE
TO LOW PRESSURE. IN ANY CASE, NEVER REDUCE PRESSURE VALUES BELOW 100 BAR.
MAKE SURE THAT RIM CLAMPING IS DONE PROPERLY AND THAT THE GRIP IS SECURE, TO
PREVENT THE WHEEL FROM FALLING DURING FITTING OR REMOVAL.
DO NOT CHANGE THE SET OPERATING PRESSURE VALUE BY MEANS OF THE MAXIMUM
PRESSURE VALVES. BUTLER S.P.A. SHALL NOT BE RESPONSIBLE FOR INJURY OR DAMAGE
ARISING FROM UNAUTHORISED CHANGES.
To properly secure rims, proceed as follows:
A.
Place tool carrier arm 3 (Fig. 29) in «rest» position by hand or with the help of the controls found on the tyre-
changer model you are working on.
B.
Move the mobile platform 1 (Fig. 29) outwards. Allow the wheel to slide along platform 1.
C.
Position chucking table 2 approximately in the centre of the wheel; move the platform towards the chucking
table and centre the wheel in the most convenient position by means of the control levers.
D.
Secure the rim with the chucking table 2 (Fig. 29)
Clamping on the central flange is always safest. Note: for wheels with grooved rims secure the wheel so
the groove is facing outward.
For rims with an inner diameter greater than 46", and which do not feature flanges with a central hole, it is
possible to secure the wheel by means of the set of extensions described in "Standard accessories".
To secure wheels with alloy rims additional protective jaws are available. They allow you to work on the
rims without damaging them (see "Standard accessories). The protective jaws are fitted onto the chucking
table's normal jaws by means of a bayonet connection.
WHEN WORKING ON LARGE SIZE TYRES (AGRICULTURAL MACHINES AND EARTH MOVING
MACHINES) TWO OPERATORS ARE REQUIRED, FOR BETTER SAFETY. WHEN HANDLING
WHEELS WEIGHING MORE THAN 500 KG, WE RECOMMEND THE USE OF FORKLIFTS OR CRANES
FEATURING AN ADEQUATE RATED WEIGHT.
NEVER LEAVE THE WHEEL FITTED ON THE MACHINE FOR A PERIOD LONGER THAN
NECESSARY FOR CARRYING WORK AND IN ANY CASE NEVER LEAVE IT UNATTENDED.
4.6
Tubeless tyres
4.6.1 Beading
A.
Secure the wheel to the chucking table, as described in the previous paragraph.
B.
Remove all balancing weights from the rim
Extract the valve and let air out of tyre.
C.
Move to work position C (Fig. 2, Fig. 4, Fig. 6).
D.
Lower tool carrier arm 2 (Fig. 30) into work position: safety connection 1 hooked.
ALWAYS MAKE SURE THAT THE ARM IS CORRECTLY HOOKED TO THE CARRIER.
E.
Check chucking table clamping pressure by looking at the pressure gauge (A Fig. 9 and 15) located on
chucking table rear end (150-160 bar). If it is not correct, open chucking table clamps. Ensure that required
pressure is restored after this command. If not, the hydraulic system is leaking.
NAV11-21-31, B956, B957, R926
1465-M002-0
GB
33