Mathematical Modeling and Validation on a New Valve Core of the Throttle Valve in MPD

Abstract

To achieve different demands for pressure control in managed pressure drilling (MPD), the relationship between the pressure difference and the valve opening was analyzed in the working process of MPD throttle. The throttle flow area equation and the flow area isosurface equation at different openings were derived. Then, the mathematical model of the throttle valve surface shape was established by solving the envelope curve of isosurface cluster. Furthermore, the shape curve equation of the valve core surface was derived and modified by applying this mathematical model. Finally, to verify the performance of this investigation, the comparison of the results between simulation and design values was performed. The results showed that the correlation between the throttle pressure difference and the valve opening is linearly related, which proves the correctness of the mathematical model for the throttle valve surface.

Experimental Validation on a New Valve Core of the Throttle Valve in Managed Pressure Drilling

“…In addition, the output values of the displacement sensor, pressure sensors, and flowmeter remain stable within an accuracy of 0.1 mm, 0.2 Mpa, and 0.5 m 3 /h, respectively; that is to say, the obtained data completely meet the accuracy requirements after being periodically filtered and averaged. On the other hand, the actual fluid density is determined to be 1682 ± 5% kg/m 3 , slightly smaller than that used in the theoretical design in Fu's study (1700 kg/m 3 ) [13]. As previously mentioned, five groups of recorded data, including the import pressure ( IM ), export pressure ( EX ),…”

“…Based on the achievements in Fu's study [13], the design parameters of the new valve cores are shown in Table 1. The theoretical profile curve of the new valve core, which meets linear − Δ relationship, is shown in Figure 2.…”

“…In this case, Fu et al [13] designed a new valve core which meets linear −Δ relationship under certain working conditions. Although the linear − Δ relationship had been validated in mathematical calculation and numerical simulation, the actual performance of the new valve core remains to be experimentally verified.…”

Failure Mechanism and Optimization of Throttle Valve Based on Computational Fluid Dynamics

“…So far, the erosion resistance evaluation of the three common throttle valves basically stops at the stage of finiteelement analysis for fluid flow field simulation [3][4][5][6][7]. The previous analysis on the flow field of throttle valve reveals that the mud flow peaks in the axial direction of the plug of the wedge valve, and the wedge surface is extremely prone to erosion under the impact of mud.…”

Criterion for non-interference of solid metal seal pair in double-offset butterfly valve

“…However, interference is found usually at the sealing surface, which results in leakage and extra friction. To avoid all these problems, optimized design of structure, especially for the sealing surfaces, is required before precise manufacturing [16,17]. Until now, several researches have been carried out to discuss the optimization strategies for the design of butterfly valve.…”