R1
R2
G1
G2
G3
G4
5
2
1
4
3
6
20
CYLINDER ARRANGEMENT
12
21
3
19
16
26
25
11
9
28
4/5
GREEN
GREEN
29
RED
7
8
21
5
15
18
10
RELIEF
VALVE
SYSTEM
CHARGING
29
29
22
27
2
1
24
14 17
23
13
CYLINDER RECHARGING
AIRCRAFT SYSTEM CHARGING
ASf0906
Servicing line
Pressure gauge, 0-200 psi (motor inlet)
1.
16.
Servicing line valve
Pressure regulator
2.
17.
Cylinder pressure gauges (6 each)
Manifold assembly
3.
18.
Lever control valves (green) (4 each)
Motor and pump
4.
19.
Lever control valves (red) (2 each)
Nitrogen storage cylinders (6 each)
5.
20.
Manifold bypass valve
Frangible safety discs (7 each)
6.
21.
Motor inlet selectro valve
Servicing line connection
7.
22.
Pump inlet valve
Filter
8.
23.
Recharge valve
Purifier
9.
24.
Manifold shutoff valve
Motor regulator
10.
25.
External air connection
11.
26.
Recharge connection
Low-pressure gauge cutout
12.
27.
Pressure gauge, 0-600 psi (low pressure)
Filter (inlet-air)
13.
28.
Pressure gauge, 0-5,000 psi (high pressure)
Check valve
14.
29.
Pressure gauge, 0-5,000 psi (manifold pressure)
15.
Figure 9-6.--A/M26U-4 system nitrogen flow diagram.
NITROGEN CYLINDERS.--The nitrogen
CONTROL PANEL.--The control panel, figure
cylinders (20) store the supply of nitrogen for the unit.
9-5, mounts the necessary valves, gauges, and
They are mounted horizontally and held in place by
plumbing components to operate the nitrogen
straps, as shown in figure 9-4. The cylinders are gray
servicing unit. The valves (4 through 10 and 17),
with two black bands, indicating that they contain
gauges (3 and 13 through 16), and plumbing
oil-free (formerly water-pumped) nitrogen. Note that
components direct the flow and control the pressure of
the cylinders do not have cutoff valves in the neck, as
nitrogen throughout the servicing system. A motor and
do most other cylinders. For this reason, you cannot
pump assembly (commonly referred to as a booster
install full cylinders on this unit; the cylinders must be
installed empty and charged in place. Nitrogen
pump), a motor regulator, a purifier, and a filter are
pressure in all cylinders should be maintained between
attached to the back of the control panel. (Only a part of
200 and 3,500 psi. The gaseous nitrogen used in this
the motor and pump assembly is shown in figure 9-5.)
system is Federal Specification BB-N-411, Type 1
NOTE: The number in parenthesis following the
(gaseous), Class 1 (oil-free), Grade B (99.50 percent
pure, low-moisture content).
component name refers to figures 9-5 and/or 9-6.
9-8
