Study On Wellbore Fluctuation Pressure Caused By Tripping With Continuous Motion Rig

With the increase in drilling costs in various regions of the world,the development of drilling tools and the Intelligent of mechanization have gradually matured and the technology has matured.However,there is still much room for the layout of drilling rigs and the improvement of ground equipment.The Continuous Motion Rig technology that came into being at this time is a new method that breaks the traditional drilling process by improving the ground equipment,and has broad development prospects.In this paper,the principle of the structure of the Continuous Motion Rig is analyzed for the specific technical principles in the double lift system technology are described in detail.Based on the continuous motion and continuous circulation mechanism of continuous drilling rigs,a new calculation model of continuous tripping fluctuating pressure is proposed.It is mainly designed that the drilling rig can achieve high efficiency and uniform speed under the conditions of Continuous Motion Rig drilling.Using the basic equations of drilling fluid flow and the law of conservation of energy,a calculation model for the conventional drilling fluctuation pressure is established.The boundary conditions and initial conditions are divided into three conditions,which are solved by combining different model calculation models.According to the characteristics of the continuous drilling rig,the new fluctuating pressure model is obtained.Finally,using the speed as the objective function,the ideal speed curve is obtained to determine the safe starting and boring speed and the ideal fluctuating pressure model is obtained.This paper mainly studies theoretically the wellbore oscillating pressure model caused by the drilling of Continuous Drilling Rigs,but the reliability and accuracy of the results require further test verification.