Appeal No. 1999-2145 Page 6
Application No. 08/781,605
parallel to one another along the length of the web and encapsulated in a resin mix which,
when cured in a coil spring configuration, returns to the same configuration after being
uncoiled (columns 3 and 4). The crack arrestor is installed around the pipe in such a
manner as to provide several layers of wrapping, which layers are biased into frictional
contact with one another over their entire areas by the “memory” present in the spiral band.
Installation is facilitated by securing with adhesive the inner end of the spiral to the pipe
and the outer end to the next inner layer, and by the application of globs of adhesive at a
few discrete points along the length of the spiral. It is explained that the device is
prevented from expanding when exposed to a propagating crack in the pipe by the friction
developed between the adjacent layers, which could be enhanced by utilizing a resin that
remained tacky even after being cured. See column 5. There is no mention in the patent
of using the device to solve the problem to which the present application is directed, that
is, reinforcing a pipeline which carries gas or liquid under pressure and has deteriorated to
the point where it has an unbreached but weakened region that has reduced its ability to
withstand the pressure of the fluid within. In this regard, in the declaration dated October
30, 1995, Mr. Fawley stated it was not obvious to him to use the coil band crack arrestors
of his ‘752 patent to take the place of conventional steel sleeves in reinforcing weakened
sections in pipelines but that he did think it was possible that these devices might be
adapted to do so, and that experiments began to explore this use, the task being
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