Appeal No. 2006-3061
Application No. 10/405,405
We concur with appellants, and do not find that the combination of the
references, regardless of which is relied upon as the primary teaching, renders
the claimed subject matter obvious. Independent claim 1, recites “delivering
cement through at least one first opening in said casing wall.” As appellants
assert, we find that Bailey teaches a method of drilling and cementing in one
trip. Bailey teaches that the casing surrounds the drill and that during drilling
the drill head and underreamer extend below the casing. See figures 1 and 2
and column 3, lines 35 through 55. When the well is drilled deep enough that
the casing is fully lowered, the drill head is retracted up into the casing and
cement is pumped through the drill string. Pressure is used (assumedly with a
fluid which is less dense then the cement) to force the cement upward into
the annulus of the casing, i.e. the cement flows out of the drill string, to the
bottom of the casing, out the bottom end of the casing (which we do not
consider to be an “opening” in the wall of the casing) and into the annulus
between the casing and formation. See figure 3, and column 4, lines 42
through 50. Thus, as shown in figure 3, the cement item 40 fills the space
between the casing and the surrounding formation, without filling the entire
casing and without cementing the drill to the casing. The examiner’s
modification would not allow this process to occur. If ports were placed
in the walls of the casing, pressure applied in the casing would not drive
the cement up the annulus, between the casing and the formation, as
shown in figure 3, rather the cement would just rise to the fill level of
both the casing and annulus. Thus, we do not find that one of ordinary
skill in the art would have been motivated to combine the references as
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