THE 3 rd INTERNATIONAL SCIENTIFIC CONFERENCES OF STUDENTS AND YOUNG RESEARCHERS dedicated to the 99
th
anniversary of the National Leader of Azerbaijan Heydar Aliyev
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other machine, formation or human related factors can also affect quality of
simulation and subsequently optimization process. Actions that are needed
to be done will be stated in appropriate section of this paper. Apart from
simulation or optimization, proper drill bit selection should be done and
design and material of the selected bit should also be taken into
consideration as resistance of the drill bit to the well conditions can be
satisfied by appropriate selection of bit and its material and proper designing.
It has to be stated that determination of UCS from sonic log results is not
significantly effective as log results can be affected by extra properties and
factors. As (George A. Cooper, 2003) it was stated, the rock strength, which
governs the rate of penetration of the drill bit, and the abrasive, which
controls the rate of wear, are the fundamental rock parameters required as
inputs for a drilling simulator., and the rock type or mineralogy, which has an
important secondary effect on both the rate of penetration and wear. George
A. Cooper and Peter Hatherly had tried to calculate these properties from
wireline logging results. It should be admitted that by using ARS data from
nearby drilled wells, perfectly matched simulation of new well cannot be
gotten as there are several affecting factors that can be inevitable to become
avoided. Issues can vary from an insufficient description of the geometry of
the bit that was or will be utilized to ambiguity about the nature of the rock
being penetrated and/or its level of pressurization. These sorts of issues can
be avoided by using a method in which the simulator is "tuned" to mimic the
drilling behavior under a known set of parameters that are as close to those
of the well under investigation as feasible. Thus, if the rate of penetration of
a specific type and style of drill bit is known at a depth and in rock types
similar to those for which some future behavior is intended, tuning the
simulator to match the known historical record allows to avoid having to
predict the drilling behavior from first principles. (George A. Cooper, 2003) It
can also be added that due to significant improvements in AI (Artificial
Intelligence), neural networks has been used for several purposes including
identifying UCS. F. Meulenkamp, M. Alvarez Grima (F. Meulenkamp, 1999)
used back-propagation supervised neural network and predicted values for
UCS are close to actual values of them. In addition to mentioned methods
above application of AI and GEP can be regarded as the most attractive
methods for determination of UCS among non-destructive methods. Once
UCS has been defined, adequate simulation of ROP can be done though
special software after which optimization of drilling process can be achieved.
By means of appropriate drilling process simulation, relevant optimization of
some parameters for efficient drilling can be operated. Specific Energy
Method has been used for appropriate bit selection and R. K. Abbas
analyzed several wells drilled and drill bits used for conducting appropriate
bit selection by using Specific Energy Method (Abbas, 2007). In addition to