Study On Erosion Mechanism Of Gas Wellhead

In recent years, with the continuous development of gas drilling, which has been widely used, the advantages of gas drilling is obvious, but the wellhead erosion of high-speed gas carrying cuttings is easy to be ignored. In the process of high pressure and high yield gas well drilling, a large number of gas carrying cuttings erosion wear wellhead, which caused to puncture failure, in serious it will cause significant casualties and irreparable economic losses. This problem will harm to the safety and environmental issues.Based on FLUENT computational fluid dynamics software, in view of the gas in the process of drilling gas carrying cuttings of gas-solid two phase flow pipeline row of wellhead sand and multifunctional four-way serious erosion problem, the corresponding erosion model was established, and the erosion mechanism has carried on the comprehensive research. This article will be according to the following several aspects analyzed the wellhead in the row of sand piping and multi-function four-way:(1) Based on the pipeline structure elements and operating conditions, simulation analysis of the pipe line of sand in different bending diameter ratio under different diameter, different corner, erosion situation, found out that with the pipe diameter ratio, and pipe diameter increases, the erosion rate will be reduced; Simulation analysis erosion situation of the pipe line in different gas flow rate and particle size of the different rock debris flow and debris under the condition of parameters, found that the erosion rate will be increased with the of flow and diameter of cuttings increasing;(2) On a gas well drilling conducted a coupon experiment and analysis the pipeline erosion features;(3) Simulation analysis of the multifunctional cross in different gas flow, debris flow and debris particle size under the condition of the working parameters, such as erosion, found that the erosion rate with the increase of the factors such as flow and diameter, the erosion rate also increase; To simulate the different by-pass outlet pressure and by-pass outlet diameter by erosion, it is found that with increasing pressure and diameter, the erosion rate with smaller;(4) Based on two kinds of erosion serious erosion of wellhead analysis, proposed to the row of sand piping and the optimal design of multifunctional cross, and simulation analysis of the optimized structure;According to the simulation of structure analysis shows that in actual engineering, under the condition of actual conditions permit, should reduce the number of row sand pipe elbow, use of large diameter, large bending diameter ratio of the exhaust pipe sand; And the use of larger diameter by-pass export multi-functional cross, at the same time in the export of certain pressure, reduce the rate of erosion.