216
MAINTENANCE
Basic machine
HBR204-MU-6-eng.doc
OPERATION AND MAINTENANCE INSTRUCTION MANUAL
THIS DOCUMENT IS THE PROPERTY OF HÜETTE BOHRTECHNIK GMBH - TOTAL OR PARTIAL REPRODUCTION IS PROHIBITED
C7
CHECKING AND TIGHTENING HEAD MOVEMENT CHAIN
Position the mast as shown, with the rotary head at its upper limit. To
check correct tensioning of the chain, you will need to act on its centreline
using a lever and measure the value X.
HEAD TRAVEL [mm]
MAXIMUM VALUE (X)
[mm]
3150
40
6900
70
8400
80
MAST WITH GEAR MOTOR
The chain tensioning device is located at the front of the mast.
Place the mast in a horizontal position
Tensioner hydraulic cylinder (A).
The chain is automatically tensioned during the
head movement.
Maximum admissible lengthening: 2%.
To compensate for the lengthening of the chain
due to wear of its components, you can remove the
links P of the chain:
-
Remove six links P on the chain (6900)
-
Remove six links P on the chain (8400)
Always remove links two at a time as shown in the
figure.
(
☞
"MAINTENANCE
– Mast with hydraulic cylinder – Reduction of number of chain links").
6.17
5.16.A
5.16.B