TRUCK SERVICE MANUAL
CHAPTER XII
FLEXIBLE HOSE, NYLON TUBING, RIGID PIPING AND FITTINGS
DESCRIPTION
Rigid (copper) tubing and fittings of different sizes
have been used to connect different air devices in the air
system.
However, flexible hoses and nylon tubing is
gaining increasingly wide usage in place of copper piping
on IH vehicles.
FLEXIBLE HOSE
Any size or length of hose can now be made locally
for service requirements.
The hose is constructed of a seamless synthetic
rubber lining or tube reinforced with one fabric braid of
high tensile steel wire which is covered with a synthetic
rubber-impregnated oil-resistant fabric braid.
These hoses can be used for air systems and air
brake systems, except air line from air compressor to air
reservoir, where the temperature will exceed 300
degrees F.
The fittings used at the ends of the flexible hose are
of the swivel type, such as that shown in Fig.
1.
The
swivel end permits one end of the hose to be
disconnected and not disturb the complete hose.
Fig.
1.
Flexible Hose Fitting
CAUTION
:
Do not try to mix different
type hoses and hose fittings.
In some
cases the hose and hose fittings may
seem to fit, but the ends may not hold up
under pressure.
If in doubt as to the
identification of the hose and/or fittings
which are being repaired, use new IH
components to make up a new hose
assembly.
Hose Assembly Instructions
When the assembly procedure in making up a hose
is being performed, each step should be finished
carefully to assure proper connections at the hose ends.
1. Remove the hose fitting and nut from socket and
hose.
Fig.
1 illustrates the swivel hose fitting.
So that the swivel nut and fitting can be removed
from the hose and socket assembly, install a
pipe adapter in the swivel nut and tighten it,
locking the swivel joint assembly (nut and fitting).
The swivel nut and fitting can now be turned out
of the hose using a wrench.
2. Separate the hose from the socket.
3. Repeat steps 1 and 2 for the removal of second
end.
4. Use a fine-tooth hack saw to cut hose to desired
length (Fig.
2).
Use care in supporting the hose
so as not to crush or damage the hose during
the cutting operation.
5. Lightly clamp the hose socket in a vise.
6.
Screw end of new hose into socket until hose
bottoms in fitting (turn hose counterclockwise).
Then back off hose 1/4 turn (Fig.
3).
Fig. 3
165
BRAKES-AIR