TM 1-1500-204-23-11
(c) Impingement Angle. The angle of the
(2) Using Heat Lamps. The following are the
heat lamp should be perpendicular to the surface, or
steps to take when using heat lamps:
the part will heat unevenly (see Figure 3-5 View C).
(a) Perform Thermal Survey.
Before
(d) Heat Sink. The presence of clamps or
using heat lamps for a repair process,
substructure members may create a heat sink drawing
a heat survey shall be performed on
heat away from the part. (See Figure 3-5 View D).
component(s) as described in Chapter
Reposition heat lamp or add additional heat lamps
as required to obtain the required temperature.
(b) Place heat lamp(s) in the same posi-
(e) Curvature. A curved surface will heat
tion as determined by the heat survey
unevenly, as shown in igure 3-5 View E. Place
in Chapter 6 to obtain the required tem-
additional heat lamps over the repair area to obtain
perature.
the required temperature.
(c) Using high temperature tape, tape ther-
(f) Shadow. The presence of obstructions
mocouple sensors or thermocouples
can cast a shadow on the repair area causing uneven
in the repair area at the minimum and
heat distribution (see igure 3-5 View F). Reposition
maximum temperature, as determined
heat lamp or add additional heat lamps as required
by the heat survey in Chapter 6. To
to obtain the required temperature.
ensure the thermocouple accurately
measures the surface temperature of
the part, use tape approximately the
(g) Emissivity. Emissivity of the surface
same color as the part surface to secure
effects surface temperature. A shiny or light color
the thermocouples.
surface has a low emissivity, which results in a cooler
surface temperature when heated, as opposed to a
dark surface which has a high emissivity and will
(d) Connect the thermocouple to a tem-
result in a higher surface temperature when heated.
perature measuring device. (The hot
bonder controller can be used for tem-
perature measuring). Check to ensure
(h) Heat Relection. The presence of vac-
proper operation.
uum bag material (i.e. breather cloth) can insulate
and relect energy away from the part being heated.
(e) Power on heat lamp(s) and continually
monitor the temperature to ensure the
(i) Ambient Temperature. Temperature the
required temperature is achieved.
ambient temperature is warm, it will take less energy
to heat the part than if the ambient temperature is
cool. Adjust the heat lamp placement accordingly.
3-7