TM 5-5420-234-14&P
BAP GENERAL WELDING MAINTENANCE.
NOTE
When weldment cracks are discovered, it is recommended that they be repaired
at the next service interval to prevent the length of the crack from increasing and
to minimize repair. The following inspection procedures are to be considered as
guidelines only. Any cracks discovered during inspections, considered more
significant--especially from a safety standpoint--should be referred to the
supervisor for weld repair decisions. This would include cracks identified in any
BAP main frame or winch frame structures and cracks that have opened and could
lengthen rapidly during BAP handling of bridge bays or transport of loaded BAP.
Refer to the Operator's Circular for Welding Theory and Application (TC 9-237)
for further information about welding procedures.
a. Weldment Points. Thoroughly inspect all weldments for cracks, chips, or other damage. BAP areas include
the main frame structure, winch frame structure, front pin lock assemblies, rear guides, center roller assembly,
and catwalks. Not all of these are specifically addressed in subparagraph b.
b. BAP Main Frame Structure.
(1)
A-Frame to Main Rails. These welds are those joining A-frame tubes and main rail tubes to angled
plate between the two tubes. Sound welds in these joints are necessary to ensure safe loading and
unloading of the loaded BAP. A crack should be repaired before it reaches 1.0 inch (25.4 mm) in
length. The combined length of multiple cracks at either of the A-frame leg joints should not exceed
2.0 inches (50.8 mm).
(2)
Winch Frame Lower Lock Pin to A-
Frame. These welds join winch
frame lower lock pin outer
circumference to A-frame tubes.
Sound welds in these joints are
necessary to ensure safe loading and
unloading of the loaded BAP. A
crack should be repaired before it
3
reaches 0.75 inch (19.0 mm) in
length. The combined length of
multiple cracks at either of the pin
joints should not exceed 1.50 inches
(38.1 mm).
(3)
Winch Frame Upper Pin Saddle
Plate to A-Frame. These welds join
winch frame upper pin saddle plate
to top beam of A-frame. Sound
welds in these joints are necessary
for safe unloading of the loaded
BAP. A crack should be repaired
1
1
before it reaches 1.5 inches (38.1
mm) in length. The combined
length of multiple cracks at either
2
plate joint should not exceed 3.0
inches (76.2 mm).