Appeal 2007-1474
Application 10/192,833
predict performance of a drilling system, where the hole cleaning efficiency model
is a measure of an effectiveness of the drilling fluid and hydraulics (Goldman, col.
11, ll. 8-10). In particular, Goldman teaches that “[i]f the hole cleaning efficiency
is low, then unremoved or slowly removed cuttings may have an adverse impact
upon drilling mechanics” (Goldman, col. 11, ll. 10-12). During the optimization
mode, Goldman uses the hole cleaning efficiency model as a “measure of
correction to the penetration rate prediction to compensate for hole cleaning that
deviates from ideal behavior” (Goldman, col. 14, ll. 24-27). “Thus, the measure of
hole cleaning efficiency (HCE) reflects the effects of lithology, shale plasticity,
hydraulics, and drilling fluid type on penetration rate” (Goldman, col. 14, ll.
27-29). According to Appellant’s Specification, rate of penetration is a drilling
performance parameter. As such, Goldman discloses using hole cleaning
efficiency to optimize a drilling performance parameter and does not disclose
optimizing at least one production performance parameter.
Johnston discloses an apparatus for enhancing production from a well bore
hole (Johnston, Abstract). Johnston’s apparatus 10 includes a cutting assembly 30
that is disposed on a drill string 21 above the pilot bit 66 (Johnston, Figure 1). The
cutting assembly 30 is not located at the end of the drill string 21, and as such, is
not a drill bit. Johnston discloses using the cutting assembly 30 as a means to
enhance production from the well bore by enlarging the size of the well bore hole
(Johnston, col. 9, ll. 6-9 and 55-59). Johnston does not disclose a method of
selecting parameters of a drill bit to optimize production.
6
Page: Previous 1 2 3 4 5 6 7 8 9 10 Next
Last modified: September 9, 2013