(4) Install pressure vacuum valve (3) over gasket
(1). Locate valve so that hinged side will be toward
small end of deck plate (2).
(5) Place steel recessed washer (4), cupped side
down, on each bolt. Install and tighten nuts (5).
6-15. Installation of Tank Deck
a. Deck Plates. Deck plates must be installed in
counterclockwise direction as viewed from the 'side
stave scaffold looking toward the center support. The
deck plates are lifted for installation by lowering the
tackle block with deck hooks (6, fig. 6-10) between the
rafter landing ring (1, fig. 6-8) and the side staves to
hook the inner end of the plate. Two men, each with a
rope and a deck hook, lift the outer end of the plate.
(1) First Deck Plate. The first plate installed is one
assembled with a rafter under each lap seam.
(a) Connect rope hooks to plate (1, fig. 6-14) and
lift it into position so that outer end is centered over a
stave seam with hangers (8, fig. 6-11) resting on the
stave chime and clips (7) resting on rafter landing ring
(2, fig. 6-14).
Figure 6-12. Assembling special deck plate.
(2) Install bolts and channels in each plate (3) from
bottom side, as shown in figure 6-12.
(3) Place blocking against boltheads and install 16-
hole gasket (1, fig. 6-13) over bolts on top side of plate
PRESSUQ'E VACUUM VALVE
STEEL RECESSED WASHER
Figure 6-13. Pressure vacuum valve installed.