TM 5-5420-203-14
Table 3-2. Suitable Replacement Bolts, Nuts, and Washers for Temporary
Replacement of Rivets - CONT
REPLACEMENT
RIVET
3/4 in. Countersunk Bolt, Cross Recessed,
Grade 8, UNC. Class 2A, ANSI-B-18.5, Zinc
Coated, (length as required).
3/4 in. Extra Duty Helical Spring-Lock
Washer, MS35340-51,
NSN: 5310-00-052-6454
3/4 in. Hex Plain Nut, Grade 8, UNC, Class
2B, ANSI-B18.2.2, Zinc Coated.
3/4 in. Flat Washer, FF-W-92.
3/4 in. Solid Buttonhead, Type 6.
3/4 in. Hex Screw, Grade 8, UNC, Class 2a,
FF-B-575, Zinc Coated (length as required).
3/4 in. Extra Duty Helical Spring-Lock
Washer, MS35340-51,
NSN: 5310-00-052-6454.
3/4 in. Hex Plain Nut, Grade 8, UNC, Class
2B, ANSI-B18.2.2, Zinc Coated.
3-11. WELDING PROCEDURES.
a. General. Welding on the bridge is limited to the tie rod housings located on the extreme ends of
the ramp sections. No other welding is authorized on the bridge. The bridge is constructed of a special
alloy aluminum (ASTM 2014-T6) which, when heated, loses its structural strength. Unauthorized
welding in specific areas and on certain components can result in the failure of the bridge, causing
severe damage and injury to personnel. Follow the procedures given, deviations are not authorized.
WARNING
Welding produces fumes and gases that are hazardous and can cause injury. Avoid breathing fumes
and gases. Ensure adequate ventilation. Arc rays can injure eyes and burn skin. Do not touch hot
surfaces or heated components, serious burns may occur. Use protective clothing, welding helmet,
and eye filter lens, Electrical shock can kill. Do not touch live electrical parts. (Refer to American
National Standard 249.1, Safety in Welding and Cutting.)
CAUTION
The welding of 2014-T6 aluminum, torch cutting of rivet heads, or the use of any procedure
that involves the application of heat to this alloy in prohibited as the structural integrity will
be jeopardized.
3-10 Change 2
