Research And Application Of On-site Centralized Control System For Closed Underbalanced Drilling In The Whole Process

With the continuous development of oil and gas exploration in China,the development direction is constantly developing towards the ultra deep sulfur bearing strata,and the deep oil and gas reservoirs contain hydrogen sulfide and other harmful gases,which seriously hinders the exploration and development of in the sulfur bearing strata.Closed underbalanced drilling technology is an efficient exploration and development technology for the development of sulfur bearing strata.On this basis,the closed underbalanced well is combined with underbalanced well completion to form a whole process closed underbalanced drilling.This technology can effectively monitor the bottom hole pressure in the underbalanced normal drilling process and realize the reasonable and rapid and accurate adaptive control of the underpressure value.It can realize the protection of the reservoir,and then realize the safety drilling and ensure the safety of the field drilling.At present,the research on the closed underbalanced drilling system has been mature and perfect abroad,the technical equipment and the supporting software system are both advanced and perfect,and have been applied in many countries and regions.However,the domestic research on the closed underbalanced drilling technology is still in the initial stage.Therefore,based on the existing closed underbalanced drilling technology,a set of integrated control system for closed and underbalanced drilling in the whole process is put forward,and the following results have been obtained:1.A centralized monitoring and control system,is designed and developed for the self-adaptive,high precision and fast response closed under balanced drilling field monitoring and control system for the sulphur bearing stratum.The on-line monitoring of all equipment in the closed and underbalanced drilling site and the fine control of the wellbore pressure are realized,and the drilling safety is ensured.2.On the basis of the existing closed underbalanced drilling technology and supporting equipment,a data acquisition and transmission system matching the existing technology and equipment is designed and developed,which realizes the integrated synchronous acquisition and transmission of the key parameters of the underbalanced drilling and the state monitoring data of all on-line equipment.3.According to the hardware system of the closed and underbalanced drilling site,combined with the integrated data synchronous acquisition system developed in this paper,the integrated real-time centralized monitoring technology of integrated closed and underbalanced drilling is formed.On the basis of this,the centralized time monitoring system software is developed,and the well field is realized.Centralized real-time monitoring of equipment data and key parameters of drilling for underbalanced drilling,and auxiliary analysis and control system to make decisions.4.Based on the Backstepping fuzzy adaptive control model of throttle back pressure,a set of dynamic analysis and control technology for closed underbalanced drilling based on ground measurement is formed,combined with the study of the wellbore pressure relationship and the principle of wellbore pressure control.5.According to the design system scheme and the field hardware system,the whole software design of the whole process closed and underbalanced drilling site centralized control system is completed,and the development and integration of the whole software system are completed.The actual analysis is carried out on the site in the two experimental wells in the Moxi area,where the text is due to the length of the article.The application results of X well are given only.The application results show that the system has a good running state and can realize the centralized monitoring and control of all on-line equipment in the closed underbalanced drilling site in the whole process,the self-adaptive,high precision,and quick response to control the bottom pressure of the well,protecting the oil layer and reducing the drilling risk and cost.The whole process closed and underbalanced drilling field control system is designed and developed in this paper.The well bore pressure and risk can be controlled,the bottom of the well is in the underbalanced state,the ground is not detected by the hydrogen sulfide,and the drilling accident can be reduced,and the safety of the drilling construction is ensured.