Manitowoc National Crane NBT30H-2, Service Manual

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CRANE INSTALLATION NBT30H-2 SERVICE MANUAL
9-2
03-20-2019 Control # 613-06
required rating, the gross axle rating is reduced to its
weakest component value.
• Wheelbase (WB), Cab-to-Trunnion (CT) and Cab-to-
Axle (CA)
- The WB, CT and CA requirements are
determined by:
- Mounting Configuration
- Boom Length
- Bed Length
The WB and CT shown in Figure 9-2 are required so the
basic NBT30H-2 can be legally driven in all states and
meet stability requirements. The dimensions given
assume the sub-base is installed properly behind the
truck cab. If exhaust stacks, transmission protrusions,
etc. do not allow a close installation to the cab, the WB
and CT dimensions must be increased. Refer to
Mounting Configuration on page 9-5 for additional
information.
• Truck Frame - Select a truck frame that minimizes or
eliminates frame reinforcement or extension of the after
frame (AF). Many frames are available that have the
necessary AF section modulus (SM) and resistance to
bending moment (RBM) so that reinforcing is not
required. The frame under the cab through the front
suspension must have the minimum SM and RBM
because reinforcing through the front suspension is
often difficult because of engine, radiator mounts and
steering mechanics. See Truck Frame Strength on
page 9-7 for the necessary section modulus and
resistance to bending moment values.
• Additional Equipment
Additional equipment recommendations are as follows:
- electronic engine control system
- increased cooling system
- extra heavy duty PTO. See page 9-5 for PTO and
Hydraulic Pump.
A conventional truck cab should be used for standard
crane mounts.
• Neutral Start Switch - The chassis must be equipped
with a switch that prevents operation of the engine
starter when the transmission is in gear.