Manitowoc National Crane NBT30H-2, Service Manual

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4
10
National Crane
03-20-2019 Control # 613-06
4-17
NBT30H-2 SERVICE MANUAL BOOM MAINTENANCE
Third (positive lock) nut installation is to be placed on each of
the extend cables. The retract cables do not require the third
(positive lock) nut.
The third nut should be hand tightened until the tapped hole
for the set screw is tangent to the end face of the wrench flat.
Install set screw into Third nut and tighten.
( OPTION 2 ) method used ONLY when space constraints
prevent OPTION 1 usage (see Figure 4-23).
TORQUE VALUES for Second Nut:
Inch Series with Coarse Threads (UNC)
Metric Series with Coarse Threads
BOOM INSTALLATION ON THE TRUCK
1. Extend and set the outriggers.
2. Attach a lifting device at the boom center of gravity and
lift the boom on the truck and lower to the boom rest.
3. Line up the boom with the attach point on the turret.
4. Install the boom pivot pin (Figure 4-4).
5. Attach a lifting device to the rod end of the lift cylinder
raise the lift cylinder so that the pivot pin can be installed
(Figure 4-4).
6. Install the lift cylinder pivot pin in the bottom of the 1
st
boom section.
7. Reinstall telescope cylinder hydraulic lines as per
removal tags.
LIFT CYLINDER INSTALLATION
1. Attach a lifting device to the lift cylinder.
2. Raise the lift cylinder to the truck bed under the boom.
3. Line up the lift cylinder with the attach point on the turret
and install the pivot pin (Figure 4-4).
4. Raise the rod end of the lift cylinder to the attach point
under the boom and install the pivot pin.
Cable end
Thread Size
Minimum
Nut
Strength
GRADE
Nut Type
TORQUE
ft lbf
1/2-13 SAE 2
Hex Jam
(HALF)
12
5/8-11 SAE 2
Hex Jam
(HALF)
31
3/4-10 SAE 2
Hex Jam
(HALF)
47
7/8-9 SAE 2
Hex Jam
(HALF)
63
1-8 SAE 2
Hex Jam
(HALF)
199
1 ¼-7 SAE 2
Hex Jam
(HALF)
203
1 ½-6 SAE 5
Hex Jam
(FULL)
250
1 ¾-5 ASTM B
Hex Jam
(FULL)
250
Cable end
Thread Size
Minimum
Nut
Property
Class
Nut Type
TORQUE
Nm
M16x2 5
Hex Jam
(THIN)
26
M20x2.5 5
Hex Jam
(THIN)
66
CAUTION
Fall Hazard!
Do not, under any circumstances, work at an elevated
height without using proper fall protection as required by
local, state or federal regulations.
WARNING
Crushing Hazard!
Ensure the lifting device is capable of supporting the
boom assembly. Death or serious injury may result.
!
!