Installation Of Flexible Hose Assemblies - Piper Lance II Service Manual

LANCE II SERVICE MANUAL
2-8b. IDENTIFICATION OF FLUID LINES. (Refer to Figure 2-4b.) Fluid lines in aircraft are often
identified by markers made up of color codes, words or geometric symbols. These markers identify each line's
function, content and primary hazard as well as direction of fluid flow. In most instances fluid lines are marked
with 1-inch tape or decals. Paint is used on lines in engine compartments where there is a possibility of tapes,
decals, or tags being drawn into the engine induction system. Certain lines may be further identified as to
specific function within a system. For example: DRAIN, VENT, PRESSURE or RETURN.
Lines conveying fuel may be marked FLAM; lines containing toxic materials are marked TOXIC in place
of FLAM. Lines containing physically dangerous materials such as oxygen, nitrogen or freon are marked
PHDAN.
The aircraft and engine manufacturers are responsible for the original installation of identification
markers, but the aviation mechanic is responsible for their replacement when it becomes necessary.
Generally, tapes and decals are placed on both ends of a line and at least once in each compartment
through which the line runs. In addition, identification markers are placed immediately adjacent to each valve.
regulator, filter or other accessory within a line. Where paint or tags are used, location requirements are the
same as for tapes or decals.
2-8c. INSTALLATION OF FLEXIBLE HOSE ASSEMBLIES.
a. Flexible hose must not be twisted on installation. A flexible hose which is installed with a twist may
have a reduced service life and may cause a loosening of the fittings to which it is attached.
b. Never exceed the minimum bend radius and avoid tight bends in flexible hose assemblies (Refer to
AC 43: 13-1, Chapter 10).
c. Never stretch a hose tight between two fittings as this may result in overstressing and eventual failure.
The length of the hose should be sufficiently long to provide 5 to 8 percent slack.
Added: 10/3/80
HANDLING AND SERVICING
1B7