Q9-3. How is nitrogen obtained on an aircraft
1. It is manufactured by using a
2. It is purchased and stored by the supply
3. It is a by-product of oxygen production
4. It is manufactured by using a nitrogen
Q9-4. A nitrogen bottle containing oil-tolerant
nitrogen has which of the following paint
A gray bottle with one black band
Figure 9-2.--Portable high-pressure nitrogen cylinder.
A gray bottle with two black bands
A gray bottle with three black bands
identification of the contents is printed in white on the
A gray bottle with no bands
cylinder. The cylinder's last hydrostatic test date is also
stenciled across the bottom of the cylinder.
Q9-5. Which type of nitrogen should NEVER be
used to purge an oxygen system?
The components of the walk-around bottle are
mounted on a one-piece welded frame designed to be
hand-carried. The cylinder assembly is fastened to the
bed of the frame by means of two quick-coupling
clamps, which provide fast removal and installation of
the cylinder. The pressure regulator is bolted to the
front of the frame, and all other servicing parts are
LEARNING OBJECTIVES: Identify the
attached to the regulator.
components of pneumatic systems. Identify
The top of the frame has four brackets for coiling
procedures for inspecting, troubleshooting, and
the servicing hose when it is not in use. The major
repairing pneumatic systems and related
components are the cylinder, the shutoff valve, the
pressure regulator, the cylinder pressure gauge, the
delivery pressure gauge, the bleed valve, the servicing
The portable high-pressure nitrogen cylinder
hose, and the recharge valve.
(commonly called a walk-around bottle) and the
A/M26U-4 nitrogen servicing unit are typical of
nitrogen servicing equipment currently in use by the
500-cubic-inch capacity reservoir designed for a
Navy. We will also briefly cover low-pressure air
working pressure of 3,000 psi. It is shatterproof and
contains a safety disc that is designed to burst between
4,000 to 4,500 psi to prevent over pressurizing the
PORTABLE NITROGEN CYLINDERS
cylinder during recharge.
SHUTOFF VALVE.--The shutoff valve controls
The walk-around bottle, shown in figure 9-2, is
the flow of nitrogen from the cylinder to the inlet of the
designed for hand carrying to remote locations for
regulator. It is a needle valve that is open only during
charging such components as accumulators, aircraft
servicing operations. The valve is closed when the unit
struts, and high-pressure tires. The user can control
is stored or the cylinder is being recharged.
delivery pressure up to a maximum of 3,000 psi.
PRESSURE REGULATOR.--The pressure
Nitrogen cylinders are painted gray with black
regulator is a single-stage assembly that allows the
stripes. One black stripe identifies oil-pumped
operator to set the delivery pressure. Once the delivery
nitrogen, and two black stripes identify water-pumped
nitrogen. In addition to the color codes, the exact
pressure is set, the regulator maintains this pressure as