Kalmar Ottawa t2, Maintenance Manual

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124 9.12 Chassis – 9 Frame, Body, Cab and Accessories
Maintenance Manual Ottawa T2 4x2
4. Make reinforcements long enough so that they can be ta-
pered and still extend beyond the critical area.
page –
Repair (Making Reinforcements, Attachment)
Reinforcements must be attached with grade 8 bolts, locknuts
and hardened washers on both ends of the bolt. This provides
a good torque surface to maintain tight bolts. Avoid attaching
reinforcements by welding. (In some cases, welding may be ac-
ceptable. Such cases include the plug weld used on strap or
web reinforcements.) Bolt holes that are enlarged or irregularly
worn may be reamed to accept the next larger bolt diameter.
For critical areas, body-fit bolts require reaming the hole to a
nonstandard size to effect an interference fit for the bolt. When-
ever possible, use existing frame holes rather than drill new
ones.
In general, when attaching reinforcements to the frame, use
bolts and observe the following:
1. Use existing holes, if possible.
2. Do not drill holes in the frame flange.
3. Holes should be made as close to the neutral axis (halfway
between the flanges) as possible.
4. Bolt holes should be no larger than those already existing
in the frame.
5. No more than three holes should be on a vertical line of the
web.
6. Holes should be at least 3/4 inch (19.0 mm) apart.
7. Holes in a reinforcement plate should be at least two times
the material thickness from the edge of the plate.
page –
Repair (Cracks in Steel Rails or Cross Members)
Type of Cracks
The straight crack and the sunburst crack are the two common
types. The straight crack will normally start from the edge of a
flange. It will progress across the flange and through the web
section of a rail. Ultimately, it will continue through the other
flange. This type of crack may result from high concentrations
of stress in small areas of the frame, excessive bending mo-
ment and torsion loading. Sunburst cracks will radiate out from
a hole in the web section of a rail or cross member. They are
caused by high loads being applied at a mounting bracket or
cross member, which is not securely or properly attached to the
rail. If cracks occur to both the rail and reinforcement of a steel
frame, they must be repaired separately. The flanges must re-
act independently to prevent localized stress concentrations.
Use a copper spacer between the flanges of cracked base rail
flanges and reinforcement flanges. Cross member mounting
flange cracks may be repaired in the same manner as side rail
cracks. However, the weld bead should be built up to provide a