Flanges and Closure Fastener Surfaces

TB 55-8100-200-24

NOTE

Welding and brazing should not be

considered critical. However, welds

should be reasonable smooth and free

of craters and other irregularities

which would indicate an unskilled or

inexperienced welder.

f. Flanges and Closure Fastener Surfaces. Straighten steel flanges which are bent or otherwise deformed, by heat-

forming and hammering. Straighten closure fastener mounting surfaces on main rotor blade box by cold-forming.

Visually check for cracks in repaired areas. No cracks allowed.

g. Sanding. Prior to leak test, clean and sand all areas which were burned during heating or welding. in lieu of

sanding, corrosion removing compound may be applied as indicated in paragraphs 3-2a(1) through 3-2a(3).

h. Leak Test. Before refinishing, test container for leakage as indicated in paragraph 2-3k. Eliminate leaks which are

disclosed, by welding. Areas that reveal leaks which are inaccessible to weld repair may be repaired with sealing

compound conforming to MIL-S-8802, Class B-1/2. Apply compound to interior of defective area in container by using an

extrusion gun, spatula, putty knife or other suitable means. Compound should be approximately one-sixteenth of an inch

thick after application. After sealing compound has cured, repeat test.

i. Distortion. Correct distortion of main rotor blade box to insure proper installation of rotor blade and ease in closure

and stacking of box. Top, sides, ends and bottom must present an overall true plane.

j. Rips and Tears. Replace ripped or torn panels in main rotor blade box which cannot be repaired by welding or

patching. Use aluminum sheet of like alloy and thickness.

k. Bumpers. Install bumpers on main rotor blade box that has been

3-6