4) Cure
a) Allow the sealant to cure as follows:
Temperature Relative Humidity Time
75°F 50% 72 Hours 120°F 50% 18 Hours
5) Sanding
a) The cured sealant can be faired out and irregularities smoothed by sanding lightly with a fine sandpaper, cloth (aluminum oxide grit) or with a gum rubber buffing wheel. Any alodine coating that is damaged by sanding shall be repaired.
E. Corrosion Preventive Paint Application
(1)
General
(a)
The corrosion control treatment consists of the application of primer and aluminized coating EC-843 or EC-843S Corogard.
(b)
Surfaces that were stripped to bare metal with paint stripper should be primed with MIL-C-8514 wash primer and MIL-P-8585 zinc chromate primer, color Y, prior to application of Corogard coating.
(c)
Surfaces with primer that could not be stripped to bare metal with paint stripper should be reactivated and touched up with BMS 10-11, type 1 primer prior to application of Corogard coating.
(2)
Equipment and Materials
(a)
Wash Primer - MIL-C-8514
(b)
Zinc Chromate Primer - MIL-P-8585, color Y
(c)
Primer - BMS 10-11, type 1. Refer to 13-1-4, Finishing Materials.
(d)
Aluminized Coating 1) EC-843 Corogard with EC-1101 aluminum powder (12.5 oz of powder per gallon of resin)(preferred) 2) EC-843S Corogard with EC-1101 aluminum powder (9.0 oz of powder per
gallon of resin)(preferred)
3) G12E25 Aeroflex Finish (optional)
(e)
Thinners and Solvents 1) Ethyl Alcohol - MIL-A-6091, or OE-760B, Grade 2 2) Butyl Alcohol - TT-B-846 3) Toluene - TT-T-548 4) Methyl Isobutyl Ketone - TT-M-268 5) BMS 3-2 Solvent, optional: TT-N-95 Naphtha 6) Normal Butyl Acetate - TT-B-838 7) Lacquer Thinner - TT-T-266a 8) Solvent – Final Cleaning of Metal Prior to Painting (Series 84) (Ref AMM/SOPM
20-30-84)
(f)
Clean, lintless cloth
(g)
Stainless steel pressure pot liners and mixing equipment
(h)
Varnish or linseed oil type tack rags
(i)
Abrasive paper, 400 grit or finer and 280 grit or finer
(j)
Metal sieve, 60-80 mesh
500
51-21-131 Page 708 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. May 15/71
(k) Corogard Paint Application Equipment 1) For EC-843, use a DeVilbiss MBC or JGA gun, EX needle and tip, 30 or 36 air cap, or Binks No. 18 gun 66 x 66, SD nozzle assembly. Fluid pressure 10 to 20 psi and 60 to 70 psi atomization air.
2) For EC-843S, use a DeVilbiss MBC or JGA gun, FX needle and tip, 704 or 765 air cap, or Binks No. 18 gun 63 x 63, PB nozzle assembly. Fluid pressure 10 to 15 psi and 50 to 55 psi atomization air.
500
May 01/98 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 51-21-131 Page 709
(3) Apply Corrosion Preventive Paint
(a) Surface preparation
1) On surfaces that are stripped to bare metal, immediately prior to application of wash primer, remove all loose dirt, dust, and lint by wiping surface to be painted with a clean, lintless cloth, wet with solvent, Series 84 (Ref AMM/SOPM 20-30-84) and squeezed to remove excess solvent. Change to a clean cloth as soon as soil appears on cloth. Wipe dry with a clean, dry cloth before solvent evaporates.
2) On surfaces coated with BMS 10-11 and BMS 10-20 primer (did not strip), reactivate per 51-2-51, Chemical and Solvent Resistant Finish -Cleaning/Painting, prior to touching up with BMS 10-11 primer.
(b) Mixing and application
1) Wash primer MIL-C-8514 (apply to completely stripped surfaces)
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(29)