Shear Performance Analysis And Control Of Coiled Tubing Blowout Preventer Ram

Due to the inherent toughness and non-fracture characteristics of coiled tubing,well control is always facing challenges.As one of the core components of coping with blowout accidents,the key to the blowout gate plate is how to effectively cut the continuous tubing at high speed and achieve well sealing.In this paper,the mechanical behavior analysis is carried out on the process of shearing coiled tubing by blowout gate plate,and the control system of blowout gate plate is explored,which provides a new theoretical basis for shearing coiled tubing of blowout gate plate.The first part: based on the Johnson-Cook constitutive model,taking CT90 coiled tubing as the research object,establish a three-dimensional model of the coiled tubing shear coiled tubing,analyze the yield and fracture criteria of the coiled tubing,optimize the shear force,transfer the model to ABAQUS software for simulation,and obtain the stress distribution of the coiled tubing and anti-blowout gate;Considering the different wall thicknesses,different lengths,different outer diameters and other factors of the oil refueling pipe,the shear force and shear stress change law of the anti-blowout gate plate were obtained,and the sensitivity analysis was carried out.The second part: taking channeling coiled tubing as the research object,analyzing the shear stress under channeling,constructing a theoretical calculation model suitable for channeling coiled tubing,analyzing the cross-sectional deformation process by V-shaped shear cutting edge angle and thickness,and verifying the theoretical model by displaying dynamic simulation analysis.The third part:Design the sensing control circuit based on fuzzy control kinematics.Establish a blow-proof gate shear continuous tubing controller,compare the traditional PID control and fuzzy PID control,analyze their respective advantages and disadvantages,combine the two into the dual redundant functional board control technology,design its dual input based on Fuzzy Logic Designer in MATLAB/Simulink,carry out traditional PID and fuzzy PID control modeling,obtain the response step curve,analyze its stable time point,and check its response accuracy.The results show that with the continuous increase of coiled tubing length,the shear stress of the blowout gate plate and the coiled tubing continuously decreases.Under different wall thicknesses and lengths,the shear stress of the anti-spray gate plate is the most sensitive to the continuous oil shear stress and the shear force of the anti-spray gate plate.In the stage of elastic deformation,the stress of the continuous tubing will increase with the increase of the load of the channeling condition,the degree of damage to the fracture of the coiled tubing will be more serious,and the stroke displacement of the gate plate will increase when the continuous tubing is completely broken.Fuzzy PID has a faster corresponding speed and is more resistant to interference.This paper provides ideas for the optimization of shear performance and control of anti-spray gate plates.