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Oilfield Technology
June
2015
wells have become the norm, and service companies that
provide innovative technological solutions are utilised
and rewarded for their contribution. At the confluence
of the technical and economic efficiency challenges,
Drilformance worked closely with one operator to provide
a novel PDC bit that not only completed the target interval
successfully, but also realised the best value from the
operator’s investment in using rotary steerable tools. Tight
target windows in the Safah and Wadi Latham fields of
Oman demand consistent directional performance. The use
of rotary steerable tools to ensure targets are consistently
achieved is common practice. In this case, the operator
needed a bit that would complement the rotary steerable
system they were using, allowing the tool to achieve both
its advertised capabilities as well as push the outer edge of
the previous performance envelope. Drilformance teamed
with operators to design and produce cutting structures
that proved successful in setting performance records with
conventional and rotary steerable tools. There are many
factors that come into play when optimising PDC bits
for high‑performance in rotary steerable applications.
Fortunately, these requirements can be achieved when
a bit vendor is committed to a holistic design approach
with the operator to produce an optimal PDC bit for an
application. The progressive profile of Drilformance bits
works seamlessly with rotary steerable systems. The
shank-less breaker design offers operators an advantage
in the selection of rotary steerable systems. The shorter
make-up length results in uncompromised three-point
geometry, so standard rotary steerable systems can
achieve build rates, which would otherwise require more
expensive, less proven high yield rotary steerable systems.
By combining all of these traits and an application
optimised cutting structure, the 516X has now been
shown as an effective bit for operators seeking optimal
performance from rotary steerable systems in Oman.
Conclusion
In today’s drilling environment, the curve and lateral
intervals are often both the most crucial and the most
expensive portion of the well. Operators cannot afford
to waste precious time tripping unnecessarily for bits
that fail to yield the planned build rates in the curve.
While drilling the lateral, if the bit walks excessively then
operators are forced to slide to correct course and lose
valuable time as weight transfer becomes erratic at greater
depths. Drilformance’s approach to these applications
is focused on unique engineering techniques tailoring
curve and lateral designs to the distinctive challenges of
each environment. The company’s curve and lateral bit
family do not require extraneous ROP killing depth of cut
management to hold tool face in the curve or minimise
walk in the lateral. These new designs are the descendants
of an unconventional lineage of bits, incorporating the
lessons of the past and the requirements of today. In today’s
budget‑conscious drilling programmes, it has never been
more important that directional bits and drilling tools
continue to provide high levels of performance. The current
generation of Drilformance curve and lateral bits aims for
higher performance through a unique design methodology
that does not waste potential ROP by bleeding off energy
inefficiently.
Figure 7.
In theHalfway formation in the Progress field, the operator ran
both theDF713T2 anda competitor bit on the samewell. TheDF713T2 drilled
46%more andaveraged 35%faster ROP. Distance is inmetres.
Figure 9.
The DF516Xwas designed specifically for anRSS application
inOmananddelivereda 62% improvement over the fieldaverage ROP.
Figure 8.
In theDoig formation in the Sundown field, the operator ran the
DF713T2 and competitor bits on the samewell. TheDF713T2 drilled 205m
further onaverage than the competitor bits. Out of 1109mand 7 bit runs, the
DF713T accounted for 827m(nearly 75%of the total drilled) with only 3 out
of the 7 runs.
