TO 35 C2-3-473-2
(f) Cure insulating compound as follows.
(b) Stop drill (0.125inch max) crack ends to
prevent futher progression of cracks.
Curing techniques can range from a simple pass-over with
a hot air gun application to radiant heat sources. The selec-
tion of equipment for the heat configuration of auxiliary
Fusion arc weld cracks using Hastelloy X
power unit when the compound is applied. Recommended
weld rod (AMS5798) with gas backup.
cure conditions are; 5 minutes at 300F (149C) or 10
minutes at 280F (138C) or for 1 hour at 250F (121C).
(d) Perform fluorescent penetrant inspection
Once the applied coating has achieved the temperature
after repair in accordance with MIL-I-6866.No cracks
required, complete foaming and cure will be completed.
A surface tack will indicate incomplete cure and additional
time at temperature is required.
(e) Replace insulation material as required.
h. Repair Turbine Housing Scroll. (See figure
Repair damaged insulating material on
turbine plenum (4) as follows:
Repair cracks in flange or body (1) as
Cut away any loose material around
Stop drill crack at both ends to prevent
progression of crack.
(b) Throughly clean area with methyl-
ethyl-ketone MEK TT-M-261 or equivalent. Dry with
(b) Hand abrade to clean up area around
clean, lint-free cloth.
(c) Apply primer (SS4155, General Electric
Cap., Silicone Products Business Dept., Waterford, NJ
12188) by wiping, brushing a spraying to a thickness of
0.1 to 0.3 millimeter. Air-dry for 1 hour.
Use solvent in a well-ventilated area. Avoid
(d) Mix insulation compound (CAGE
excessive skin contact or prolonged inhalation of
64101, P/N V-657, General Electric cap., Silicone Prod-
vapor. Do not use near open flame or in area
ucts Business Dept., Waterford, NJ 12188) as follows.
where high temperatures prevail.
Thourghly mix 10 parts of resin and 1 part catalyst. Addi-
tion of the catalyst should be held within 10 percent of
the specified amount. Mixed compound will have a 4 to 6
hours application life at 77F (25C) during which time the
compound is most easily applied.
Clean turbine housing scroll with solvent
(e) Apply insulating compound as follows.
Trowel compound onto cleaned area. Total thickness of
P-D-680, Type II or equivalent. Dry with clean, lint-free
insulation material after repair shall be 0.20 to 0.40 inch.