TM 5-4310-385-13
SECTION II. EQUIPMENT DESCRIPTION
1-7. PURPOSE OF THE AIR COMPRESSOR. An electric motor driven compressor for tools, tire inflation and general
shop use.
1-8. CAPABILITIES AND FEATURES.
a.
Two stage compressor provides compressed air at 5 cfm and 175 psi.
b.
Electric motor driven.
c.
Magnetic motor starter with thermal relay protects motor against overload.
d.
Pressure switch provides for automatic compressor cut-in at 160 psi and cut-out at 190 psi.
e.
Tank safety relief valve to prevent damage to compressor and injury to personnel.
f.
Automatic unloading of compressor unit upon machine shutdown.
g.
Air discharge system with inflator gage can be used to directly inflate tires to proper pressure.
h.
Tank mounted pressure gage gives constant reading of air pressure in tank.
1-9. DESCRIPTION OF COMPRESSOR COMPONENTS.
a.
Air Tank (1). A 20 gallon air tank with welded boss openings for check valve, pressure gauge, pressure switch,
outlet valve, and safety relief valve. Has a welded platform base for electric motor and compressor mounting.
b.
Safety Relief Valve (2). Tank mounted valve with relief setting of 200 psi. Pull ring for manual check of operation.
c.
Check Valve (3). Spring and poppet valve that prevents air from returning to the compressor head from the tank.
Has threaded opening for unloader line fitting.
d.
Aftercooler Tubing (4). Air discharge tubing from high pressure cylinder head to check valve and air tank.
e.
lntercooler Tubing (5). Finned copper tubing between the high and low pressure cylinder heads. Provides heat
dissipation between the high and low pressure cylinder heads.
f.
Compressor Unit (6). A two stage air cooled pump driven by pulleys and V-belts. Rated at 5 cfm at 175 psi.
g.
Electric Motor (7). Three phase, 2 hp induction motor. Shaft mounted pulley powers larger compressor flywheel.
Wired in series with pressure switch and magnetic motor starter.
h.
Hose Rack (8). Welded to motor starter frame to provide hose storage.
i.
Motor Starter (9). Contacts are magnetically closed when power is applied. Contains a thermal or melting relay
which opens the circuit when a current overload is sensed. Enclosure contains ON/OFF switch (10) and RESET button
(11).
j.
Pressure Switch (12). Controls operating pressure range between 160 psi (cut-in) and 190 psi (cut-out) with a
differential of 30 psi. Diaphragm senses operating pressure and opens and closes contacts. Adjustable pressure setting.
Contains a pressure relief fitting for the unloader line.
k.
Shutoff Valve (13). Hand operated globe valve to shut off air flow from tank to air hoses.
I.
Air Hose (14). 50 ft. hose couples to shutoff valve and inflator gauge assembly. Stores on tank hose rack.
m.
Unloader Line (15). Runs between check valve and pressure switch. Upon compressor shutdown, provides
release of air pressure in cylinder heads and aftercooler for easier startup.
n.
Inflator Valve and Gauge Assembly (16). Connected to 50 ft. air hoses. Hand lever releases air pressure.
Sight glass provided for inflation reading. Quick connect couplings between gauge and inflator valves (one regular tire
valve, one special application valve).
o.
Pressure Gauge (17). Provides continuous reading of tank pressure between 0-200 psi.
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