Piper Aircraft Corporation Malibu Mirage PA-46-350P, Airplane Maintenance Manual

Page: 233 / 1956

PIPER AIRCRAFT, INC.
PA-46-350P, MALIBU MIRAGE
MAINTENANCE MANUAL
PAGE 7
Feb 28/07 1K7
20-00-00
8. Flareless Tube Assemblies
The use of flareless tube fittings eliminates all tube flaring. An operation, referred to as presetting, is
necessary prior to installing a new flareless tube assembly. Presetting is performed as follows:
A. Cut tube to correct length. Ensure ends are perfectly square. Deburr inside and outside of tube. Slip
nut, then sleeve, over the tube. (Refer to Figure 6, Step 1.)
B. Lubricate fitting and nut threads as specified in table contained in Figure 6.
C. Place fitting in a vise (refer to Figure 6, Step 2). Hold tubing firmly and squarely on seat in fitting.
(Tube must bottom firmly in the fitting.) Tighten nut until cutting edge of sleeve grips tube. This point
is determined by slowly turning tube back and forth while tightening nut. When tube no longer turns,
nut is ready for final tightening.
D. Final tightening depends upon type and size of tubing. On aluminum alloy tubing up to and including
half inch outside diameter, tighten nut from 1 to 1-1/6 turns. On aluminum alloy tubing over half inch
outside diameter, or steel tubing, tighten nut from 1-1/6 to 1-1/2 turns.
E. After presetting the sleeve, disconnect tubing from fitting and check the following points (refer to
Figure 6, Step 3):
(1) Tube extends 3/32 to 1/8 inch beyond sleeve pilot to prevent blow off.
(2) Sleeve pilot contacts tube. A maximum clearance of 0.005 inch for aluminum alloy tubing, or
0.015 inch for steel tubing, is acceptable.
(3) A slight collapse of tube at sleeve cut is permissible. No movement of sleeve pilot, except
rotation, is permissible.