Manitowoc National Crane NBT40 Series Service Manual

CRANE INSTALLATION NBT40 SERVICE MANUAL
9-12 Published 8-01-2017 Control # 287-11
PTO REQUIREMENTS
Horsepower
The crane is equipped with a piston hydraulic pump (1,
Figure 9-8) that supplies 75 gpm to the crane functions. The
pump shaft needs to turn at proper RPM as shown below to
provide these flows. The PTO torque rating need to be at
least 475 lb-ft (641 N.m) or 89 HP (67kW) per 1000 RPM of
PTO shaft speed.
Direct PTO Mount
Most pump installations can be direct mounted to the PTO
using adapter assemblies available from the PTO supplier. If
the pump is direct mounted, its weight should be supported
by a strap between the pump and the transmission. The
splined shaft coupling in a direct mount pump installation
requires lubrication. A special multi-lube (#200S Silver
Streak) is applied to the shaft during original installation and
should be reapplied to the shaft the on PTO semi-annually
thereafter.
PTO Ratio
Pump shaft speed is determined by truck engine RPM and
PTO ratio:
Pump Shaft Speed = Truck Engine RPM x PTO Ratio
The following PTO ratio and engine speed combinations
provide proper pump shaft speed which is the recommended
maximum speed for the NBT40 pump.
The speeds shown below are optimum operating speeds.
The engine must be operated at a speed such that the
horsepower developed is adequate to run the pump under
pressure and provide the required flow.
Select as slow as an engine speed as possible to reduce fuel
usage, while ensuring PTO ratio does not exceed engine
torque capacity especially at low engine speeds.
Pump Rotation
The hydraulic pump must be installed so that the pump
rotates the same direction as the arrow on the pump
housing. Make certain which direction the power take off
output shaft rotates before selecting a clockwise (CW) or
counter-clockwise (CCW) rotation hydraulic pump. Either
CW or CCW rotation pumps are available and are marked
clearly with a directional arrow on the pump housing.
Do not confuse engine crankshaft rotation with power take
off rotation. If the power take off shaft rotates opposite the
engine crankshaft, it is turning in a CW direction when
viewed from the rear of the truck. If the power take off shaft
rotates the same as the engine crankshaft, it is turning in a
CCW direction when viewed from the rear of the truck.
FIGURE 9-8
7606
1
Engine Optim Speed Range
(RPM)
PTO Ratio - 2200
RPM PUMP
2000 110%
1800 122%
1600 138%
1500 147%
CAUTION
Rotating the pump in the wrong direction damages the
pump.
Reference Only

Manitowoc National Crane NBT40 Series Specifications

General

Brand	Manitowoc
Model	National Crane NBT40 Series
Category	Construction Equipment
Language	English