Kick Prevention, Detection, and Control: Planning and Training Guidelines for Drilling Deep High-Pressure Gas Wells

Abstract

SPE Member Abstract Conoco has developed generalized planning and training guidelines for well control on deep, high-pressure gas wells. These guidelines include a thorough review of gas behavior, causes of kicks, pressure indicators, and kick indicators as they pressure indicators, and kick indicators as they are applied to high-pressure gas wells. The guide-lines also emphasize the fundamentals associated with constant bottomhole pressure methods of well control. After the basic principles are reviewed, the characteristics of oil base mud are discussed. These characteristics are then related to all of the basic principles. Following this review, there is a practical example based on experiences Conoco had on a deep, high-pressure gas well drilled with oil base mud. Finally, there is the development of procedural and equipment requirements that are the procedural and equipment requirements that are the result of having systematically addressed well control principles for deep, high-pressure gas wells. Introduction Within the industry, there have been general concerns about how drilling with oil base mud affects the ability to detect and control kicks (references 1,2). This concern has become greater as oil base mud has become more commonly used for deep, high-pressure gas wells. There are three phenomena associated with oil base mud in phenomena associated with oil base mud in high-pressure gas wells that can have an effect on well control operations: Behavior of deep, high-pressure gas kicks Characteristics of heavily weighted oil mud in deep wells Gas solubility in oil Each of these alone can have a significant impact on kick prevention, kick detection, and well control. The impact becomes considerably greater as the three phenomena are combined. Conoco's progress on well control for deep, high-pressure gas wells, including those drilled with oil base mud (OBM), can be attributed to two principal activities: participation in two principal activities: participation in two Drilling Engineering Association (DEA) projects and detailed planning for drilling deep, high-pressure gas wells. As a result of these activities and plans to drill additional high pressure wells, Conoco is developing the technical approach and training requirements to address potential well control problems associated with high-pressure gas wells drilled with oil base mud. The principles and guidelines discussed in this paper have evolved from the work done for five wells, with planned TD's ranging from 15800 feet to 23000 feet. One of the objectives of this paper is to present a well control overview, parts of which can be used by research, parts of which can be used by research, engineering, or operations and the whole of which can result in safe, effective practices at the well site. Some of the concepts presented herein are no different for high-pressure gas wells than for any other drilling program, but they are included for completeness. Other concepts are discussed in greater detail to point out phenomena that could be important for a given well. Since effective well control is dependent on a combination of factors, this guide presents the basic principles and offers some examples of how their interactions can impact well control operations. This paper does not present recommendations that are universally applicable to deep, high-pressure wells. P. 665