(1) This coating prevents hydraulic fluid damage to titanium parts exposed to temperatures of 250°F or higher.
CAUTION: TO PREVENT CORROSION, CARE MUST BE TAKEN TO AVOID ANY SALT DEPOSITS, INCLUDING FINGERPRINTS, ON AN UNPREPARED TITANIUM SURFACE. HANDLE TITANIUM WITH CLEAN WHITE COTTON GLOVES.
B. Equipment and Materials
WARNING: SUBSTANCES LISTED BELOW MAY BE TOXIC OR FLAMMABLE. USE WITH ADEQUATE PRECAUTIONS.
(1)
Solvents
(a)
Stoddard solvent or equivalent
(b)
BMS 3-2 (Optional: TT-T-95, aliphatic naphtha)
(2)
Stripper
(a) Turco 4338
WARNING: THIS IS AN ALKALINE, STRONGLY OXIDIZING AGENT. USE CLEAN MILD STEEL CONTAINERS AND AVOID ALL CONTACT WITH EYES, SKIN, OR CLOTHES. WEAR HEAVY RUBBER GLOVES AND GOGGLES. CONTACT OF THE POWDER WITH ORGANIC SOLVENTS SUCH AS ACETONE OR MEK MAY RESULT IN AN EXPLOSION.
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(3)
Cleaners
(a)
Oakite 204, or Cee Bee 280, or equivalent MIL-C-25769, Type I or Type II cleaner
(b)
Oakite 61 (Optional: Wyandotte Altrex or equivalent aluminum type alkaline cleaner)
(c)
Isopropyl Alcohol - Federal Specification TT-I-735, or equivalent
(d)
Distilled or deionized water
(4)
Rubber gloves and clean white cotton gloves
(5)
Cheesecloth
(6)
(Optional: coarse aluminum wool)
(7)
Brushes or cellulose sponges
(8)
Soft, high quality bristle brushes
(9)
Mild steel tanks and handling equipment (for Turco 4338 solution)
(10)
Coating: Andrew Brown Company B-2000
(11)
Spraying equipment
(12)
Sandblasting equipment as required
(13)
Abrasives - 100 to 250 (Tyler Series) Mesh Silica, Alumina or Silicon Carbide
C. Prepare for Coating Application
(1) Sand blast surfaces to be coated to remove all contamination and previous coating.
CAUTION: IF SANDBLASTING EQUIPMENT IS USED INSIDE OF AIRPLANE, INSURE THAT NO PARTICLES ABRADE INTERIOR SURFACES NOT BEING TREATED. DO NOT SANDBLAST TITANIUM DUCTS. IF YOU SANDBLAST THE TITANIUM DUCTING, YOU CAN CAUSE PERMANENT DAMAGE.
(a) For extensive applications remove titanium parts from airplane (Ref Chapter 21, Air Conditioning, or Chapter 30, Ice and Rain Protection).
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(2) (Optional) Proceed as follows:
(a)
Remove titanium parts from airplane.
CAUTION: CHEMICALS USED FOR PRETREATMENT ARE VERY CORROSIVE TO AIRPLANE STRUCTURE. IF PARTS ARE NOT REMOVED FROM AIRPLANE, TAKE STRICT PRECAUTIONS TO ENSURE NO SOLUTION CONTACTS OTHER COMPONENTS OR STRUCTURE.
(b)
Replace parts showing metal deterioration.
NOTE: A bright metallic surface with etching is evidence of deterioration.
(c)
Clean hydraulic fluid.
NOTE: A light glossy brown film, a dull black residue, or a bare surface, are evidence of hydraulic fluid contamination.
1) Scrub with cheesecloth or aluminum wool dampened with Oakite 61 or equivalent.
NOTE: If aluminum wool is used, it should be sufficiently coarse to produce a dull surface. Avoid a shiny or polished surface.
2) Swab rinse.
3) Remove excess moisture with cheesecloth.
4) Repeat steps 1), 2), and 3) until a water-break-free surface is obtained.
(d)
Clean any remaining foreign matter. 1) Use minimum amount of Stoddard solvent or equivalent to moisten cheesecloth. 2) Rinse thoroughly with water. Use high-pressure rinse if possible. 3) Repeat steps 1) and 2) until a water-break-free surface is obtained. 4) Dry
(e)
Remove previous coating. 1) Prepare Turco 4338 stripper per directions on container.
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WARNING: ALKALINE, STRONGLY OXIDIZING. USED AT 200°F. WEAR GOGGLES AND HEAVY RUBBER GLOVES AND AVOID ALL CONTACT. USE MILD STEEL CONTAINERS AND HANDLING EQUIPMENT.
2) Immerse parts in stripper 30 to 40 minutes.
3) Water rinse.
4) Wash with air water spray.
5) Repeat steps 2), 3) and 4) until black coating is removed.
(3) If further chemical pretreatment is required, contact Boeing for procedure. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：737 AMM 飞机维护手册 结构 STRUCTURES(32)
