National Crane 600H, Руководство по обслуживанию

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NATIONAL CRANE
08-19-2022 Control # 092-13
4-5
600H SERVICE MANUAL BOOM
4
22. Loosen and remove four capscrews attaching the
bottom pad plate to the second section. Slightly lift third
section, and remove pad plate.
23. Slide 3
rd
section out of 2
nd
section. Removal of side
pads is optional, as the side pads have adequate
clearance for boom disassembly. If removal of side pads
is required, tag all shims, pads and corresponding
locations for proper re-assembly.
24. Loosen and remove all remaining capscrews and wear
pads from boom sections.
Boom Disassembly Alternative #2
The 600H boom design allows for removal of the extend
cylinder from the rear of the boom without complete
disassembly of the boom sections. This procedure allows
quick access to the cylinder, retract cables, and various
internal boom components for service or replacement.
1. Remove hoist. Please refer to the hoist removal section
in this book.
2. Gaining access through rear of boom, loosen capscrews
retaining the extend cable anchor in the rear of the 3
rd
section as well as the anti-two-block wire clamp on the
anchor assembly. Loosen and remove two capscrews
retaining lock bar to extend cylinder. Remove lock bar
3. Extend boom 24 in (61 cm). Loosen and remove the
nuts which secure the extend cables to the cable anchor
plate. Remove nut from anti-two-block spade bolt.
4. Drape extend cables and anti-two-block wire inside
boom, and slide cable anchor plate out of the side of the
hoist mount.
5. Loosen and remove two capscrews, lockwashers and
spacers which anchor the extend cylinder rod butt plate
to the rear of the 1
st
section.
6. Using appropriate lifting device, lift extend cylinder up
and out of retaining slot on rear of 2
nd
section.
Retracting cylinder with an external hydraulic power
source during this step may be necessary.
7. Pull cylinder out through rear of boom assembly
approximately one-half the length of the cylinder.
Turning of the butt plate and rod 90 degrees may aid in
sliding cylinder through hoist mount area. Keep extend
cables tight to minimize the possibility of damage.
8. Lift extend cylinder up until it contacts inside of boom
section. Remove anti-two-block wire clamp from extend
cable anchor. Remove anchor by pulling anchor and
cables out rear of boom. A slight angle applied to the
anchor as it is being pulled to the rear will permit easier
removal.
9. Continue to pull extend cylinder and cables out of rear of
boom. Remove extend cables and store in an area to
minimize the possibility of damage.
Additional Maintenance, Disassembled
Boom
1. Clean all boom sections and inspect for wear, dents,
bent or bowed boom sections, gouged metal, broken
welds or any abnormal conditions. Repair or replace as
required.
2. Inspect all sheaves for excessive groove wear or
abnormal rim wear. Replace as required.
3. Inspect all sheave bearings for excessive wear or cut
liner material. If installed bearing diameter is 0.015 in
(.38 mm) larger than the pin diameter, bearing must be
replaced. Any cut or gouge which causes the bearing
liner to be distorted is cause for bearing replacement.
4. Clean and inspect all cable assemblies according to the
wire rope inspection procedures in this section. Pay
particular attention to any wire breakage within 6 ft (180
cm) of the end connections. Replace cable assemblies
as required. Lubricate all cable assemblies before
reinstalling them in the boom.
5. Inspect all sheave pins for nicks, gouges or pitting due to
rust in the bearing surface area. Replace if any damage
is evident.
6. Inspect anti-two-block wire full length for damage, check
for electrical continuity.
7. Clean all boom sections and inspect for wear, dents,
bent or crooked boom sections, gouged metal, broken
welds or any abnormal conditions. Repair or replace as
required.
8. Inspect all sheaves for excessive groove wear or
abnormal rim wear. Replace as required.
9. Inspect all sheave bearings for excessive wear or cut
inner liner material. If installed bearing diameter is 0.015
in larger than pin diameter, bearing must be replaced.
Any cut or gouge which causes the bearing liner to lose
strands is cause for bearing replacement.
10. Clean and inspect all extend and retract cable
assemblies according to wire rope inspection
procedures in this section. Pay particular attention to
any wire breakage at the end connections. Replace
cable assemblies as required. Lubricate all cable
assemblies as required. Lubricate all cable assemblies
before reinstalling them in boom.
DANGER
Do not, under any circumstances, work at an elevated
height without using proper fall protection as required by
local, state or federal regulations.
REFERENCE ONLY