National Crane 600H, Руководство по обслуживанию

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NATIONAL CRANE
08-19-2022 Control # 092-13
4-25
600H SERVICE MANUAL BOOM
4
10. Wipe and inspect all cylinder internal and external
surfaces for damage.
11. Remove seals and bearings from packing gland and
piston. Replace all seals and bearings.
12. Reassemble shaft and piston set in the proper order with
external snap ring, large washer, internal round section
ring, packing gland, stop tube, piston to shaft o-ring,
piston, and locknut. Loctite locknut onto shaft using type
680 according to Loctite recommendations. Torque
locknut to 600 ft-lbs (813 Nm).
13. Grease piston assembly and install the shaft assembly
with piston, o-ring, stop tube, packing gland, internal
round ring, large washer, and external snap ring into
barrel assembly.
14. Using special drive tool, drive the packing gland into the
barrel assembly.
15. Insert one end of round ring into groove in barrel
assembly and spiral the ring into groove with straight
blade screw driver.
16. Slide large washer into position on end of packing gland
and retain with the external snap ring being sure that
snap ring contracts completely and properly into the
snap ring gland groove.
TELESCOPE CYLINDER REPAIR
NOTE: The following Telescope Cylinder Repair,
Disassembly and Assembly instructions are NOT
for the six section boom telescope cylinder. For
repair information on the six section telescope
cylinder contact Crane Care. See the DANGER
warning for the six section boom repair and service
on page 4-3.
Telescope Cylinder Disassembly
1. After cylinder has been removed from boom, place on
supports and place drain pan under holding valve and
cylinder head area.
2. Retract cylinder shaft with oil from the hydraulic system
until about 12 in (30 cm) of shaft is extended. The barrel
must be filled with oil to prevent a compressed air
chamber being formed which could result in injury at
disassembly. Relieve any trapped hydraulic pressure
which might remain in the cylinder.
Pressure line from a porta-power
or hydraulic line from the crane
circuit valve. Read step 5 and 6
before performing this step.
Shaft extended
about 12 in
Retaining Ring
Washer
Snap Ring
Cylinder Barrel
FIGURE 4-13
Boom Extend
Boom Retract
FIGURE 4-14
REFERENCE ONLY