JIB CRANES WITH AN ARTICULATED ARM MANUALLY ROTATED

DONATI SOLLEVAMENTI S.r.l. - Via Roma, 55 - 21020 Daverio (VA) - Tel. 0332 942611 - Fax. 0332 948597
6.4 Adjusting and regulating
6.4.1 Adjusting the rotation brake of the crane arm
REMAINING RISKS IF ON THE CRANE DURING THE ADJUSTMENT OF THE BRAKE
DANGER / RISK
Risk of crushing in case of
contact with the rotation arm
when adjustments of the brake
are being made.
BAN / WARNING
Warning! Exposure to moving
parts can cause danger.
55
OBLIGATION / PREVENTION
• Adjustments of the brake must be
carried out by qualified
maintenance staff.
• Use of protective gloves and, if
necessary, safety harnesses.
• The brake of the jib crane must be adjusted so as to guarantee the stability of the
arm in any of its positions with a maximum load.
• The braking is mechanical and is ensured by two pushed clutch plates which with
adjusting screws work on a pressure plate, in contact with the rotation tube of the
arm.
• The clutch plates, which are asbestos-free, are subject to wear in relation to the
intensity of service and when, after a period of use, there is a tendency of the arm to
take up preferred positions putting itself in different positions to those required
when the rotation action has not happened, adjustment must be made.
To adjust the brake of the arm of the jib crane proceed as follows:
WARNING! When this operation is carried out at a height, on a scaffolding or
other mobile equipment, the use of safety harnesses is obligatory.
1. Regulate the slidability of the rotation of the arm, using the braking system by means of the
adjusster screws 1 ( fig.55 ).
2. Carry out the check of planarity of the arm with the help of a level. Carry out such a check rotating
the arm by 90° to the left and to the right ( fig.56 ).
fig.55
fig.56
If the adjusatment of the brake has been made several times and after the last
adjustment the stability of the arm is not guaranteed, replace the clutch plates.