1
2
3
3
3
TM 9-4940-568-20
10-10
10-4. FRS GENERAL WELDING MAINTENANCE.
NOTE
When weldment cracks are discovered, it is recommended that they be repaired at the
next service interval, or as noted 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 stand point, should be referred to the supervisor for weld repair
decisions. This would include cracks identified in any main structural areas (A-Frame,
main rail flanges and crane frame base) and cracks that have opened and could lengthen
rapidly during loading/unloading operations.
a.
Weldment Points. Thoroughly inspect all weldments for cracks, chips or other damage. Areas include the
front and rear corner fittings, FRS flatrack crossmembers and the hookbar. Inspect welds for acceptable crack
length limits using the following guidelines.
(1)
A-Frame Interface (1). This area includes the A-Frame channel to main rail interface, the top and
outboard wrapper plates, and the front wrapper plate and gussets. Solid welds in this area are necessary
to ensure safe loading and unloading of the FRS flatrack. A crack should be repaired before it has
reached 2 in. (5 cm). The combined length of multiple cracks at any one location should not exceed 4 in.
(10 cm).
(2)
Hookbar (2). These welds are located at the base of the hookbar casting on the A-Frame of the FRS
flatrack. These welds secure the hookbar to the structure and are subjected to a significant portion of the
total load during loading and unloading operations. Cracks should be repaired prior to reaching 1 in. (2
cm) in length. The combined length of multiple cracks at this location should not exceed 1 1/2 in. (4 cm).
(3)
Corner Fitting and Adjacent Structure (3). The corner fittings of the FRS flatrack are used for
transportation. They may be used to secure the FRS flatrack to a trailer or bribbing for the crane. Due to
the high loads that these fittings can see in a transport mode, the crack should be repaired before reaching
1/2 in. (1 cm) in length. The combined length of multiple cracks at any one location should not exceed
1/2 in. (1 cm). This applies to cracks present in the adjoining structure also.
