Design And Application Of Bottom Hole Pressure Monitoring System Based On Vertical Pressure Measurement

In the process of drilling,the monitoring technology of bottom hole pressure is one of the key technologies to ensure safe drilling.Having a precise knowledge of the bottom hole pressure and improve the precision of controlling the pressure for bottom hole are the key factors to ensure the smoothness of drilling construction operations.There are two main methods for monitoring bottom hole pressure.One is to use PWD(Pressure While Drilling)to measure the bottom hole pressure in real time,and the other to use the hydraulic model and related parameters in the drilling process to calculate bottom hole pressure.At present,the downhole measuring instruments of PWD are often used to measure downhole data during drilling.Foreign countries have matured in PWD technology development.Overseas companies such as Baker Hughes,Halliburton,Schlumberger,Schlumberger,and Weatherford have all developed their own PWD products.Although the use of PWD measuring instrument can achieve real-time bottom hole pressure quickly and safety monitoring.However,the cost of PWD construction and service is very expensive,and in the process of drilling operations,due to high temperature changes and other conditions,the data uploaded to the ground is distorted,the data cannot be successfully returned to the ground,and even the PWD does not work properly.Comparing with the relatively mature research on the monitoring technology of bottom hole pressure in the drilling process abroad,the domestic research on this technology is still in the initial stage of development.Therefore,how to use the traditional calculation of bottom-hole pressure,to solve PWD data distortion,no acquisition and no return PWD measuring instruments on the data,using ground equipment accurate monitoring downhole pressure to be key of the development for domestic drilling technology.Therefore,this paper fully investigates the bottom-hole pressure monitoring technology at home and abroad.Based on this,this paper has conducted in-depth research on the bottom-hole pressure monitoring mechanism and monitoring algorithm.A set of bottom hole pressure calculation model based on vertical pressure is proposed,combined with data mining algorithms,and a bottom hole pressure monitoring and analysis model is established to develop and integrate corresponding supporting systems.The specific research tasks are as follows:1.After extensive investigations of borehole pressure monitoring methods at home and abroad,this paper proposes a bottom hole pressure monitoring and analysis method based on vertical pressure and data mining algorithms.At the same time,a real-time monitoring and analysis system for bottom hole pressure of conventional drilling is established in combination with a corresponding data acquisition system to realize bottom hole pressure monitoring and dynamic analysis during conventional drilling and ensure efficient and safe drilling.2.In this paper,by studying the monitoring method of bottom hole pressure,and analyzing the advantages and disadvantages and practicality of various monitoring methods,a method is proposed to calculate bottom hole pressure by measuring the vertical pressure.And establish a corresponding bottom hole pressure monitoring model,combined with data mining algorithms,establishing a bottom hole pressure correction model of different algorithms,At the same time,by simulating various model and analyzing the advantages and disadvantages,the algorithm model is optimized,and the appropriate bottom-hole pressure correction model is selected to monitor and check the pressure at the bottom of the well so as to accurately grasp the bottom hole pressure and ensure the construction safety.3.This paper designs and develops a corresponding data acquisition system based on conventional drilling construction techniques and supporting equipment.The system implements functions,Including the collection function of integrated data which combining logging data,PWD measurement data and ground monitoring data.4.This paper combines bottom hole pressure monitoring and analysis models.Complete the overall system design,system architecture design and supporting hardware equipment.At the same time,combined with the data requirements of the well bottom pressure monitoring model,Establishing a supporting database of bottom hole pressure monitoring and analysis systems.Providing effective data support for drilling construction safety.5.The software system designed based on the established bottom hole pressure monitoring data includes a complete set of bottom hole pressure monitoring and analysis system.At the same time,it has passed field application tests.The results show that the system is stable and reliable,with good monitoring results and meets the design requirements.The software system has a good field application prospects.6.The bottom hole pressure monitoring and analysis system designed and developed in this paper can not only solve the problem that the PWD measuring instrument cannot transmit the data or the distortion of the transmission data,It is also possible to calculate the corrected bottom hole pressure,using the data collected by the integrated logging tool without a PWD measuring instrument,to ensure safe drilling at the construction site...