Design Study On Completion String Of High Temperature And High Pressure Gas Wells

Along with the development of high temperature and high pressure drilling well completion and the discovery of more and more high temperature and high pressure oil and gas fields, the new well completion design concept and technology must be developed in the petroleum industry. A lot of experiences are obtained through the rapid development process of recovering high temperature and high pressure oil and gas fields, such as high efficiency, reliability. Besides, risk analysis of economic optimization of well completion design decisions gradually start to consider the influence of technology, safety and environmental protection etc.. At present, there are two outstanding problems existing in the development of high temperature and high pressure drilling and completion. First, the cost of high temperature and high pressure drilling rig operation is very high, the efficiency and reliability must be ensured in the completion process to reduce the loss of non production time. This makes the new technology and special tools be developed to reduce the time of tripping and rig running time. Second, high temperature and high pressure oil well repair costs are very high, and later repair work should be avoided, the reliability of oil and gas field development time should be improved.The development of high temperature and pressure of oil and gas well has the characteristics of high investment, high risk, high output and funds. Also, fast recovery is required. Ignoring any details of these problems will cause the waste of a large amount of manpower, material and financial resources, and even the abandon of whole wells. Completion is an important part of high temperature and high pressure oil well construction, and it is the foundation of the development of high temperature and high pressure oil and gas field. The aim is to ensure the safety production of oil and gas wells and to prolong the life of oil and gas wells. In the production process of high temperature and high pressure reservoir, the deformation of the pipe string, the pressure drop and the temperature drop in the initial stage of the production is large, as well as the special seal pressure and so on. At present a complete system of theory and technology is not yet developed for the high temperature high pressure completion string and tool selection. Thus the development of gas well completion pipe string is of important practical significance for safety design research. Through tubing carrying liquid, preventing tubing erosion, hydrate prevention, tubing strength check, sealed annulus pressure change analysis, perforating string vibration and shock absorption measures, the high temperature and high pressure well completion string design was carried out. The design method was successfully applied to the high temperature and high pressure gas field in the South China Sea, and it is of guidance for the future development of other offshore high temperature and high pressure gas fields.