High pressure High temperature (HPHT) wells technologies while drilling

The goal of this research is to discuss the various objective of using Innovative drilling technologies in high pressure and high Temperature wells. The gas and oil Industry is growing rapidly and becoming more demanding because of the new reserves are being found in difficult atmospheres. Wells are being drilled at higher depth under High Pressure and Temperature situations (HPHT) which requires reliability of system to resolve the complexity because of High pressure and Temperature. Now a day HPHT is very famous word in petroleum industry. With higher pressures and temperatures, moving into deeper wells shows up the operating working window limited and therefore much problematic than conventional wells. Few of the problems are found in this work when coping with a well setting in HPHT. Well control knowledge is required to maintain a secure and safe well during drilling operations. Selection of BOP’s is much important during the well control of HPHT wells. During operations of conventional well, it is important to maintain the well pressures in the formation just above the pore pressure and below the fracture pressure. This is to prevent the formation fluids inflow within the wellbore or into the formation of drilling mud. Therefore, the diagnosis of pore pressure is quite essential in the design of the casing and drilling mud. By using MPD & UBD technologies we came across to mitigate the many problems during the drilling operations. This thesis is divided into five chapters and mainly concentrated on the well control and drilling operations under high pressure and temperature scenarios. The effort is made to complete this study to discuss the main considerations of HPHT wells. The first chapter gives a brief summary of High pressure and High Temperature wells. It also provides the information about classification of HPHT wells, their challenges and Technological gaps in the industry related to HPHT wells. The second chapter explains the drilling fluids and their selection criteria in HPHT wells. This chapter discusses the various types of drilling fluids used while drilling in HPHT zones and also concentrated on selection of drilling fluids and their related problems. It also explains the behavior of drilling fluids and their rheological parameters and their effect on high temperature and pressure. The third chapter is mainly focused on the wellbore instability and related issues. It explains the problem related to the wellbore instability and prevention techniques in order to avoid the wellbore instability under high temperature and pressure condition. The fourth chapter highlights the drilling operations and their working in HPHT conditions and zones. This chapter is mainly about the use of drilling techniques under high pressure and temperature condition and the tools used. It discusses the use of MPD and UBD and their comparison in HPHT wells. Lastly, the Fifth chapter represents the most important aspect of petroleum industry i.e. well Control. this chapter includes the aspects of well control aspects are explained, mainly with focus on kick detection, kick causes and the well kill methods and procedures and the prevention techniques to avoid major accidents.