JUNTTAN PM 20L Operator's Manual page 76

JUNTTAN
Daily operation section
When you are ready to drive the pile which you have positioned according to the
previous sections, release all the controls into their neutral positions.
n NOTICE
It is recommended to keep the leader foot on ground during hammer operation. This
way the vibrations from the impact will not be transmitted to the machine and the
leader foot cylinder will not be damaged if the pile suddenly races down.
When you drive piles you should keep the drive cap, the hammer guide claws and the
leads of the ram block always properly creased. The pulling with the winches is
prevented, if the piling switch is on position 1 or 2. The pilot pressure from lifting side
of the hydraulic control block is released.
LIMITATION OF USE OF THE PILING HAMMERS
General
As with all machinery there is a limit as to the operational conditions under which the
machinery is expected to function safely, efficiently and longer lasting. A general
definition for the piling hammers limit is described below.
Limitation of use
Under normal piling conditions, the hammer must be stopped when a 10 blows or more
per 25 mm of penetration is recorded, over 6 consecutive intervals of 25 mm (For
example 60 blows per 150 mm).
Continued use of the hammer over this limitation will result in hammer breakage within
a short period of time. The hammer must be stopped immediately. For more information
and guidance please contact your local dealer or manufacturer before proceeding
beyond this limitation.
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