National Crane 600H, Руководство по обслуживанию

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BOOM 600H SERVICE MANUAL
4-8
08-19-2022 Control # 092-13
4. Note all pad locations and tag accordingly.
5. Inspect pads for wear using previously mentioned
inspection criteria.
6. Assemble top/rear wear pads to the top of the 2
nd
and
3
rd
boom sections with the cam plates. Wear pads can
be inserted from the hoist mount end of the boom. Install
capscrews through holes in outer boom sections.
7. The wear pad on each side at the top/rear of the boom
can be adjusted over a range of 3/16 in(4.8 mm) by
rotating, end for end, the wear pad and plate or the wear
pads and plate independently. This is possible because
the holes in these parts are offset from the center. The
holes are 0.06 in (1.5 mm) off center in the plate and
0.03 in (0.8 mm) off center in the wear pad. Various
combinations of rotation of these parts allow the
adjustment.
a. Adjust pads until they are within 0.03 in (0.8mm) off
center in the wear pad. Various combinations of
rotation of these parts allows the adjustment.
b. Torque retainer capscrews, refer to Fasteners and
Torque Values pg 1-7. Failure to properly torque
capscrews will cause loss of preload and cause
excessive side clearance between sections.
Front Bottom Pad Replacement
NOTE: Refer to Inner Wear Pad Calibration pg 4-8 of this
section to determine Wear Pad shim thickness.
1. Extend boom approximately 4 ft (120 cm) out.
2. Using an appropriate lifting device, sling around the 3
rd
section boom and lift it up until weight is removed from
the bottom pads in the front of the 2
nd
and 1
st
boom
sections.
3. Loosen and remove the four capscrews holding the pad
doubler plate in between the 3
rd
and 2
nd
sections,
remove plate, remove pads from this plate. Note all pad
locations and tag accordingly.
4. Loosen and remove the four capscrews holding the
bottom front wear pads to the 1
st
section, remove pads.
Retract cable adjustment ends may have to be loosened
during this step. Note all pad locations and tag
accordingly.
5. If disassembly of cables was required:
- Replace all wear pads.
- Wear pad plate.
- Re-torque retract cables.
INNER WEAR PAD CALIBRATION
1. With a pair of inside/outside calipers, measure the inside
width of the outer section (Wi) at the front and back of
the boom and record the smallest measurement. If the
section has cylinder anchor bars, take a measurement
directly in front of these bars
2. With the inside/outside calipers, measure the outside
width of the inner section (W0) at each side pad location.
Record the largest measurement.
W
i
CYLINDER
ANCHOR BARS
OUTER
SECTION
FIGURE 4-3
W
o
2 PLCS
TOP
W
o
1 PLC
BOTTOM
INNER SECTION
t
wp
t
wp
FIGURE 4-4
REFERENCE ONLY