Figure 9-11. - Stave chimes bent.
vertical position from the outside. In proper position, offsets are at the lower left and upper left comer.
DRESSING STAVES. - The end of the chime at the offset and the plain section, top and bottom, must be slightly bent for ease in installation. The end of the chimes at the offsets (fig. 9-11) must be bent inward (towards each other). The end of the plain chimes is bent outward (away from each other). The bends are made with a few sharp blows from a hammer.
Along the right seam of each stave, as it will be put in place with the chimes out, place a strip gasket on the outside at the row of bolt holes. The gasket material comes in rolls and is cut to proper length for each stave. Cut the gasket material so that it covers and projects one bolt hole past the top and the bottom chimes.
Insert 1/2- by 1 l/4-inch bolts through the stave joint channel, the stave, and the gasket, in that order. Omit one bolt about 10 inches from the bottom of the stave and other bolts at about 2-foot intervals, so the driftpins can be inserted to align the staves with one another before bolting them together.
PREPARING OUTER EDGE OF TANK BOTTOM. - AS no channels are used with the bolts inserted through the chime (outer edge) of the bottom, it must be raised to provide clearance to insert and tighten the bolts following installation of the staves.
Raise the chime and block it up with short lengths of 3- by 3- or 4- by 4-inch timbers at equally spaced intervals around the perimeter of the bottom. Set the blocking about 16 inches from the outer edge.
Install the strip gasket to coverall of the bolt holes. When one roll of gasket material is used up and a new one is started, the overlap should extend over two bolt holes. Apply putty at each end of the overlap. Insert a wedge gasket underneath the gasket at the laps formed by the bottom plates.
Insert 1/2- by l-inch bolts through all of the bolt holes in the bottom and the gasket, in that order, except in the lap seams of the bottom. Insert 1/2-by 1 l/2-inch bolts in each lap seam.
Omit the rubber gaskets and steel recessed washers on all of the chime bolts.
FIRST STAVE. - The first stave (fig. 9-12, #l), installed on the bottom, must be the one fitted with a pipe coupling of the same size as the tank supply pipe.
Place the stave over the proper bolts, so the stave straddles a radial seam in the bottom. As a result, each subsequent stave will straddle a radial seam. Install four equally spaced catch nuts to hold the stave in position. Run the nuts down by hand to fasten the stave loosely. The nuts are not tightened until the last stave in the ring is in place.
Two special gaskets are needed. The wedge gasket fills the space by the lap offset at the vertical seam, and a radii gasket is installed underneath the gasket at the bottom and the top chimes of the stave. Radii
Figure 9-12. - Installing first stave.
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