TM 55-1520-240-23-6
7-4.2
TUBE BENDING (AVIM)
(Continued)
7-4.2
Tube ends shall be square to tube
centerline. OD of tube shall be free
of scratches 1-1/2 inches from tube
ends to ensure leak-proof swage at
end fittings.
NOTE
If desired, tube may be cut oversize
and trimmed to desired length after
bending.
1.
Cut tube (1) to required length (APP E-50, chart
A) (Task 7-5). If tube is cut oversize, mark both
ends of tube to finished length. Use marking
pencil (E271).
2.
Mark tube (1) for the number of bends to be
made as follows (APP E-50, Chart B):
a.
Identify one end of the tube as the X-end.
Mark distance from finished X-end to each
bend with a line (1.1) around the tube.
b.
Mark a reference line (1.2) about 2 inches
long, along the length of the tube at the
X-end. Sight down the length of the tube
from the X-end with the reference line facing
up (12 o’clock).
c.
At each bendline (1.1) rotate the tube
clockwise the number of degrees shown in
the DIAL C SET column. Make a reference
line (1.3) about 2 inches long, along the
length of the tube at the bend line.
NOTE
Use the line at the X-end as the zero
degree reference for tube rotation at
each bend line.
7-23
