Manitowoc National Crane 500E2 - Page 137

National Crane Published 08/16/19 Control # 112-05 9-21
500E2 SERVICE MANUAL CRANE INSTALLATION
9
5. If the frame through the rear suspension doesn't meet
minimum specifications for RBM and section modulus
as shown on “Truck Frame Strength” table, it can be
reinforced by adding an angle type of reinforcing as in
Figure D. See “Section Modulus tables, Table B” for the
required size of reinforcing. Strip all easily removable
equipment from the frame through the suspension such
as spring stops, etc. Butt the reinforcing angle up
against the reinforcing forward of the suspension and
mark the areas that will require cutting so that the angle
will slide up around the spring hangers and against the
existing truck frame and forward reinforcing. Torch out
the marked areas in the long leg of the angle deep
enough so that the lip of the angle can be slid up from
the underneath the frame to contact either existing truck
frame or spring hanger brackets (if they extend down
below the existing truck frame). If reinforcing angle is to
be welded to truck frame, cut out plug weld hole pattern
as in Figure B. Slide the reinforcing angle up from the
bottom, butt it to existing forward reinforcing and weld
rear suspension reinforcing to forward reinforcing.
Replace as much of the spring hanger cut out areas as
possible and butt weld these pieces in.
If reinforcing angle is to be bolted on, drill hole pattern and
install bolts according to Figure C. Reinforce spring hanger
cut outs and the weld area, suspension reinforcing to forward
reinforcing by adding bars under these areas. The bars
should be of the same thickness, width and yield strength as
the reinforcing angle lip, and should be long enough to
extend at least 6 inches (152 mm) beyond either side of the
weld or cut out areas. Weld these reinforcing bars to the
underside of the reinforcing with length-wise welds. Do Not
Weld Across The Flanges. Replace any equipment that
had been removed.
Weld 6 (152)
Skip 6 (152)
Weld 6 (152)
Skip 6 (152)
Weld 12 (304)
Reinforcing under crane
Cut outs Replace as much
material as possible. Butt weld
Overload spring stop.
Remove and replace.
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Truck frame (REF)
Reinforcing (REF)
6 (152)
6 (152)
6 (152)
6 (152)
Butt weld
NOTE: All dimensions are
inches (millimeters)
Figure D