waratah HTH622B SIII, Руководство оператора

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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 handle stems
safely with minimal damage to the carrier.
2
1
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3
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1—Front or compression cut
2—Back or release cut
3—Barber chair
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.
T7M7G6M,00004B3-19-11OCT21
Quarter Cutting
2
1
TX1019722—UN—09JAN08
1—Front or compression cut
2—Back or release cut
This method is used on various occasions to gain better
control when felling. Use a saw cut, placed at the base
of the tree in the direction of the fall, approximately a
quarter of the diameter into the tree. The harvester head
is then moved to the back of the tree ready for falling.
CAUTION: Prevent possible injury while felling.
Always work on one tree at a time and complete
the tree cut. Failure to follow the safety
precautions may lead to serious injury.
Ensure the back cut (2) is placed higher in the tree than
the front cut (1); approximately one-quarter of the tree
Operation: Special Techniques
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