TM 9-2320-280-34
21-4. FRAME INSPECTION AND REPAIR (Cont'd)
NOTE
Transverse tear, crack, and break repairs (all welding on frame)
will use reinforcements (dutchman/fishplate), and be heli-arc type
as given in TC-9-237, providing tears, cracks, or breaks are
repairable (refer to task c.)
1.
Crack repair. (All welding on frame will be heli-arc type as given in TC 9-237.) Cracks not
extending across two adjacent faces of the frame rail may be welded.
(a) Stop drill crack with 1/8 in. (3 mm) drill hole.
(b) Vee-notch crack.
(c) Heli-arc weld crack with approved welding rod.
(d) If reinforcement or fishplate is to be added, grind weld flush to surface of rail.
(e) Install reinforcements (dutchmen/fishplate) and lap-weld.
2.
Welded reinforcements or fishplates will not be less than 6 in. (15.2 cm) in length along frame rail.
3.
Bolt on reinforcements or fishplates will not be less than 8 in. (20.3 cm) in length. Long bottom
edge of fishplate will be heli-arc lap welded to frame component.
4.
Puncture holes only in side faces of frame rails may be repaired with combinations of fishplates
and/or reinforcements. Welded type only will be used. Puncture holes in bottom face are not
reparable, replace frame rail.
5.
Bolted on repairs will use grade eight bolts, hardened washers and nuts. Use proper torque when
tightening nuts. (Refer to Appendix D when no other torque value is provided.)
6.
Bending repair:
WARNING
When performing frame rail straightening repairs accomplished
with power driven mechanical or hydraulic means, all personnel
will stand clear of vehicle. Failure or malfunction of equipment
may cause injury to personnel.
(a) Do not attempt to repair a bend when:
(1) Buckling to a height of 1/4 in. (6 mm) on any one face of frame box is involved. If more
than one face of frame box is involved with bending, replace part.
(2) Bending also includes more than very minor twisting.
(3) If part is bent in two directions, replace part.
(4) If bending involves a collapse of one or more faces of frame box at a suspension or body
attachment point, replace part.
(b) When performing straightening repair with frame on vehicle:
(1) Use spreader plates or wood blocking to distribute chain force to avoid damage to frame
box section.
(2) Be sure to loosen sufficient length of frame to allow frame force points to move without
causing other damage.
(3) Restrain vehicle movement in both directions along line of force application.
(c) Vertical bends, except at end sections, require removal of frame rail or crossmember from
vehicle. Straightening is done by using before and after dimensional measurements.
(d) Application of bulk heating to frame components is not authorized; metal properties are
irreversibly degraded.
(e) At the conclusion of a bend repair, carefully inspect welds in vicinity of repair and area of
force application. Any evidence of cracking or chipping of welds must be repaired. (Refer to
step 2.)
(f) Spot paint repaired areas using Chemical Agent Resistant Coating (CARC), following
TM 43-0139, Painting Instructions For Field Use.
7.
Front and rear wheel alignment checks (TM 9-2320-280-20) will be made after all frame repairs.
21-9
