waratah HTH618C, Руководство оператора

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Operation: Special Techniques
T7M7G6M,00004B3 -19-15JUN20-1/1
Use of Double Cuts
NOTE: Poor tree form encountered during felling,
delimbing, and processing, makes it necessary to
use special techniques to be able to safely handle
stems with minimal damage to the carrier.
The use of double cuts allows the tree to fall freely,
while minimizing butt damage. It is recommended larger
diameter trees are double cut to prevent saw bar damage
and “barber chairs” (3).
Two cuts; a front (or compression) cut (1) and a back (or
release) cut (2) are advised for larger trees. Using the
two-cut method means the top or tip of the saw bar is not
travelling over the direction of the fall, which can cause
damage if the tree moves forward and down.
Position the harvester head to the front, or in the desired
direction of fall of the tree. Make the front cut with no
sideways or upward pressure. The cut should finish when
the cutting unit is square with the direction of the fall. The
back cut should be higher than the front cut, allowing the
tree to fall a level and avoid splitting wood towards the
cutting unit. A slight sideways and upward pressure,
according to the lean and size of the tree, should be
applied as the tree is being cut.
The aligning of the two cuts is important, as there may be
holding wood left on either side, which may cause damage
to the saw unit if they are not parallel. Over-cutting the
release cut with the front cut can also stop the cutting unit
from returning if the tree begins to fall.
Trees of varying diameters may mean the alignment of
the harvester head needs to compensate for the cuts to
be parallel.
1— Front or compression cut
2— Back or release cut 3— Barber chair
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—UN—09JAN08
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