Figure 9-62.—Corrugated ribbon packing.
and 2000 psi). It is easily removed since it does
not harden.
PACKING OF FIXED JOINTS
Figure 9-63 shows gasket material used for
fixed joints. At one time, fixed joints could be
satisfactorily sealed with gaskets of compressed
asbestos sheet packing (view A of fig. 9-63).
Today the 15 percent rubber content of the
packing makes it unsatisfactory for modern, high-
temperature, high-pressure equipment. Two types
of gaskets (metallic or semimetallic) are in use in
present day high-temperature and high-pressure
installations. Gaskets of corrugated copper or of
asbestos and copper are sometimes used on low-
and medium-pressure lines.
Serrated-face metal gaskets (view B of fig.
9-63) made of steel, Monel, or soft iron have
raised serrations to make a better seal at the
piping flange joints. These gaskets have resiliency.
Line pressure forces the serrated faces tighter
against the adjoining flange. The gaskets shown
are of two variations.
Spiral-wound, metallic-asbestos gaskets (view
C of fig. 9-63) are made of interlocked strands
of preformed corrugated metal and asbestos
strips, spirally wound together (normally called
the FILLER), and a solid metal outer or centering
Figure 9-63.—Fixed-joint gaskets. A. Sheet asbestos gaskets. B. Serrated-face metal gaskets. C. Spiral-wound, metallic-asbestos
gaskets.
9-43
