KINGPIN REPLACEMENT (ALL EXCEPT XM1007) (Con't).
Compressed air used for cleaning or drying purposes, or for clearing restrictions,
should never exceed 30 psi (207 kPa). Wear protective clothing (goggles/shieid,
gloves, etc.) and use caution to avoid injury to personnel.
Using air-arc process, remove welds securing upper surface of kingpin (1) and plug welds from kingpin
`[mushroom." Care must be taken to minimize damage to bolster plate.
Remove kingpin (l).
Grind area of the bolster plate under kingpin "mushroom" flush so that new kingpin (1) will lie flat on bolster
install kingpin (l). Locate holes in kingpin top in the same manner as the one removed.
Preheat kingpin (1) and bolster plate to 150F(66C) and maintain temperature throughout welding process.
Weld kingpin "mushroom" to bolster plate with in. (6.35 mm) fillet weld 2 in. (5.1 cm) long at four equally
spaced points on edge of flange and plug weld the holes in the "mushroom." Welds are to be in accordance
with TB SIG 222. Use 100,000 psi (689,500 kPa) electrode.
inspect weld with dye penetrant or magnetic particle inspection, No cracks are allowed. Any cracks found must
Prime and paint top of kingpin (1) and bolster plate (TM 43-0139).
Replace semitrailer middle metal plate, deck, and flooring as required.