(9)
Immerse part in magnesium touch-up solution (Dow 1) (Method No. 402G) for one-half to one minute followed by rinse in clean tap water.
(10)
Immediately oven dry part at 250F (121C) for two hours.
(11)
Plug all holes and mask all areas not to be painted.
(12)
Apply primer (Method No. 402J).
(13)
Air-dry 15 to 30 minutes, then bake one hour at 175 to 225F (79 to 107C).
(14)
Apply color-coat (Method No. 402K).
(15)
Air-dry 15 to 30 minutes, then bake one hour at 175 to 225F (79 to 107C).
Repair Page 429 Apr 1/05
20-00-02/70-00-01
C. Method No. 406C: Gouge and Scoring Repair
Repair gouges, scoring, etc., on magnesium alloy parts as follows:
WARNING: SOLVENT VAPORS ARE TOXIC AND FLAMMABLE. DO NOT INHALE VAPORS. OBSERVE FIRE PRECAUTIONS.
USE CORRECT PERSONAL PROTECTION. PROCEDURES THAT NEED GRIND/MACHINE WORK WILL CAUSE LOOSE PARTICLES THAT CAN GET IN YOUR EYES.
(1)
If build up is necessary, machine damaged surfaces while maintaining dimensional limits specified in the applicable Overhaul Manual. Clean machined surfaces using solvent (Federal Specification P-D-680, Type I) (SECTION VII) or equivalent.
(2)
If machining was necessary, perform a fluorescent penetrant inspection (SECTION III).
NOTE: Manufacturer furnished surface preparation and application instructions CMC Specifications PS-1, PS-2, PS-3, and PS-5 with purchase of epoxy repair compound.
(3)
If gouging or scoring repair is needed, hand finish to remove raised metal.
(4)
Mask areas not requiring repair before applying epoxy repair compound.
(5)
Prepare surfaces to be repaired per CMC Specification PS-1.
(6)
Apply epoxy repair compound (SECTION VII) by spray, brush, or blade application per CMC Specifications PS-2 or PS-3 to fill gouges, scoring, or build up surfaces as required to maintain dimensions listed in the applicable Overhaul Manual.
(7)
Allow compound to air-dry for 24 hours or cure in an over per CMC Specification PS-5.
7. Replacing Inserts, Studs, Bushings, and Pins
NOTE: See Method No. 416A, 416B, and 416C for repairing damaged/oversized diameters with inserts and/or plugs.
A. Method No. 407A: Loose or Damaged Thread Inserts Replacement
Step (1) describes the repair or non-Keenert thread inserts, and Step (2) describes the repair of Keensert thread inserts.
(1) Remove and replace non-Keensert thread inserts as follows:
(a)
Use long-nosed pliers (SECTION VII) to remove loose or damaged inserts.
WARNING: SOLVENT VAPORS ARE TOXIC AND FLAMMABLE. DO NOT INHALE VAPORS. OBSERVE FIRE PRECAUTIONS.
(b)
Clean hole from which insert was removed, using solvent (Federal Specification P-D-680, Type I) (SECTION VII) and remove corrosion if present.
Repair Page 430 Apr 1/05
20-00-02/70-00-01
(c) Install new insert three-quarters to one and one-half turns below surface of countersink. Remove tang, if applicable, using long-nosed pliers (SECTION VII) or blunt tool and hammer (SECTION VII).
NOTE: Use a modified screwdriver, or a rod, with the correct outside diameter to fit inside diameter of insert and slotted to fit over tang of insert, to install new insert.
(2) Remove and replace loose or damaged Keensert thread inserts as follows:
NOTE: Refer to Table 402 and Table 403 for Keensert dimensions and installation data.
CAUTION: DO NOT PERMIT THE DRILL TO TOUCH HOUSING OR DAMAGE CAN RESULT.
(a)
Use standard drill to remove insert material between Kees. (See Figure 403.)
(b)
Bend Kees inward and break off.
(c)
Remove insert with an "easyout" type tool.
WARNING: SOLVENT VAPORS ARE TOXIC AND FLAMMABLE. DO NOT INHALE VAPORS. OBSERVE FIRE PRECAUTIONS.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：标准施工手册 STANDARD PRACTICES MANUAL 20-00-02/70-00-01(79)
