For the pressure control in the process of drilling, the non-linearity in the throttle valve pressure drop tuning is a serious problem. In this paper, using the computational fluid dynamics (CFD) method, numerical simulations of the throttle valve in the Tarim Oilfield are carried out, and the structural relationship between the valve opening and the pressure drop is analyzed. The structure of the valve core is improved on this basis, and the linearity of the relationship between the valve opening and the pressure drop is greatly improved. It is shown that the improved throttle valve can better satisfy the requirements of the drilling pressure control technology, the improved throttle valve pressure drop characteristics are significantly improved with better linearity, and in the opening of 20% to 70%, the linear correlation coefficient is 0.973. the adjustability of the throttle valve pressure drop and, therefore the safety of MPD, are greatly improved. With the improved core structure of the valve, the vortex phenomenon of the internal flow field is ameliorated with the maximum speed being reduced by 29.78%, also the throttle manifold erosion prevention is improved.

pressure drop characteristics  /  throttle  /  managed pressure drilling  /  linearity