ROP optimization and modelling in directional drilling process

Abstract

Rate of penetration (ROP) is one of the most critical parameters affecting virtually all drilling characteristics including technical, operational, economical, safety and other aspects of it. ROP evaluation may provide important information which can be applied to improve drilling efficiency and decrease the cost of drilling per meter. The choice of ROP for every single case is dependent on variety of factors such as diameter of the well, target depth, present geological formations, pressure, water depth, hole cleaning, types of drilling tools that will be used. Additionally, there are different requirements depending on what country or state the well is located in. All these factors must be considered while choosing the proper ROP for drilling of every oil well interval. In this master thesis several subsea wells of Norwegian Continental Shelf and several wells of Sakhalin Offshore location in Russia have been reviewed. Last technological and scientific trends and tendencies have been analyzed. A literature study of related topics has been done. Possible solutions have been suggested for every analyzed case based on well design, depth, cost of work and technologies and geological environments. Analyses have been carried out primarily by means of mechanical, hydraulic, stress, loads and safety calculations in different software applications including Landmark software applications, Weatherford software applications as well as calculations in Matlab software with applying different calculation methods. Based on the results of calculations, implemented models and analyses of the related materials possible well designs and methods of increasing and optimizing the ROP were found for every considered case.