Manitowoc National Crane 800D - Page 214

INSTALLATION 800D
9-20
Published 5-27-2018 Control # 039-06
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 in (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.
CUT OUTS-REPLACE AS MUCH
MATERIAL AS POSSIBLE-BUTT WELD
REINFORCING UNDER CRANE
(REF) TRUCK FRAME
BUTT WELD
6 in
(152 mm)
OVERLOAD SPRING STOP-
REMOVE AND REPLACE
WELD 6 in (152 mm)
SKIP 6 in (152 mm)
WELD 6 in (152 mm)
SKIP WELD ALL
BARS WITH
ALTERNATE
WELD ALONG
BOTH EDGES
(REF) REINFORCING
6 in
(152 mm)
6 in
(152 mm)
6 in
(152 mm)
SKIP 6 in (152 mm)
WELD 12 in (305 mm)
FIGURE D
9445
Fo
r
Reference
Only