TM 55-1925-286-13&P
OPERATOR, UNIT, AND DIRECT SUPPORT MAINTENANCE
AIR COMPRESSOR FOR
INLAND AND COASTAL LARGE TUG (LT)
EQUIPMENT DESCRIPTION AND DATA
EQUIPMENT CHARACTERISTICS, CAPABILITIES, AND FEATURES
The compressed air system is comprised of two 2-stage, pressure lubricated, air cooled air compressors, two
starting air receivers, one ship's service air receiver, two air dryers, six pressure regulators, three automatic
drains, and miscellaneous gauges, valves, and piping. The technical characteristics of these components are
detailed in the equipment data paragraph in this work package. Theory of operation is outlined in WP 0003 00.
LOCATION AND DESCRIPTION OF MAJOR COMPONENTS
1. Port Main Engine Starting Air Regulator (figure 1, item 1). The regulator reduces the pressure of the starting
air entering the port main engine's starting motor.
2. SSDG 2 Starting Air Regulator (figure 1, item 2). The regulator reduces the pressure of the starting air
entering the SSDG 2 starting motor.
3. Air Compressors (figure 1, item 3). The compressors supply all of the compressed air for use onboard the
LT.
4. Ship's Service Air Receiver (figure 1, item 4). This receiver stores all of the air for the ship's service air
system, ensuring that an ample reserve of compressed air is available for the vessel's use.
5. Starting Air Receivers (figure 1, item 5). These two receivers store all of the compressed air for the starting
air system. Air from these receivers is supplied to the starting systems of the main engines, SSDG 2, the bow
thruster engine, and the pump drive engine.
6. Ship's Service Air Regulator and Bypass Manifold (figure 1, item 6). The regulator controls the pressure of air
entering the ship's service receiver from the starting air receivers. The bypass manifold permits bypassing of
the regulator in the event of regulator failure.
7. Bow Thruster Engine Starting Air Regulator (figure 1, item 7). The regulator reduces the pressure of the
starting air entering the bow thruster engine starting motor.
8. Pump Drive Engine Starting Air Regulator (figure 1, item 8). The regulator reduces the pressure of the
starting air entering the pump drive engine starting motor.
9. Starboard Main Engine Starting Air Regulator (figure 1, item 9). The regulator reduces the pressure of the
starting air entering the starboard main engine's starting motor.
DIFFERENCES BETWEEN MODELS
At the time of issue for this manual, only hull number LT-803 had received the higher capacity air compressor
upgrade. Therefore, no differences between models currently exist. As other vessels are upgraded, this manual
will be revised to reflect those installations. Differences between models will be identified at that time.
0002 00-1
