against the scaffold, as shown in figure 9-19. Locate
each plate so it straddles a vertical seam of the side
staves in the approximate installation position,
ADJUSTMENT OF CENTER
LADDER Check and adjust the ladder to the correct
height before the installation of the deck plates. he
distance from the top of the tank bottom to the outer
face of the top flange of the dome is 9 feet 6 9/64 inches.
Raise or lower the ladder as required.
Place a jack under one of the ladder steps. Adjust
the ladder so that in the final position, one set of the
holes in the bottom of the rails line up with the holes in
the brace. Lock the jack Insert the bolts through the
proper bolt holes in the brace to match the top holes in
the rails. Apply the nuts to the bolts. Tighten the bolts.
Unlock and remove the jack.
When all of the deck plates have been installed on
the tank, check the height to the outer face of the top
flange of the manhole dome above the top of the tank
bottom. If not the required height, adjust the ladder
until it is the correct dimension. Insert the bolts in
aligned bolt holes and tighten the nuts.
INSTALLATION OF FIRST DECK
PLATE. The first plate installed should be a plate
with a vent (fig. 9-19, #2). The remaining plate, fitted
with a vent, must be installed directly across the tank
from the first plate with a vent. Attach two rope deck
hooks to the small end of the plate while it stands
against the scaffold (fig. 9-13). Guide the large end of
the plate and pull the plate in place by means of a haul
line. Lower the large end of the plate over the proper
bolts in the top chime of the staves, so it will straddle a
vertical seam. The small end of the plate will drop over
the proper bolts. Release the hooks. Apply four equally
spaced catch nuts to the bolts through the large end of
the plate. One catch nut will be sufficient to hold the
small end in place. Do not tighten the bolts.
PLATE. Install a gasket over the bolts at the left lap
seam of the plate (fig. 9-17, #3 and #4). Face the small
end of the plate #4. Install this plate and all of the
remaining plates to the left of the first plate or in a
counterclockwise direction around the tank Raise the
plate. Place the right lap seam of the plate over the
bolts in the left lap seam of the first plate #4 and the
large end over the proper bolts in the top chime of the
Install the nuts to six equally spaced bolts in the
lap seam of the plates. Install the nuts on all of the
bolts in the chime. Finger tighten all of the nuts. As
the deck will have to be adjusted as the plates are
installed, do not tighten any bolts until the deck is
completely installed. Raise or lower the center support
ladder as required to fit the plates in place.
INSTALLATION OF INTERMEDIATE DECK
PLATES. There are 12 intermediate plates. The
special plates remaining are installed to suit field
LAST DECK PLATE. Raise the last deck plate
before the next-to-last plate is installed Raise the right
lap seam of the first deck plate (fig. 9-20, #l). This is
necessary to permit the installation of the last plate.
Figure 9-20.Installing last deck plate.
Figure 9-21.Outside ladder installed.