Prediction of Erosion Damage in a Choke Valve Working in Severe Slurry Conditions

Wellhead choke valves, frequently used to control oil and gas flow rates from producing wells in the petroleum industry, may experience loss of material due to the impingements of solid particles within the extraction fluids. This phenomenon, called impact erosion, is a serious concern to engineers, as it can result in loss of performance or even failure of the devices. Being capable to identify the valve components which are most vulnerable to impact erosion and provide quantitative estimation of the useful life of the chokes under actual production conditions may open the way to improved design and maintenance. The present contribution focuses on the use of Computational Fluid Dynamics techniques for predicting the impact erosion of a choke valve working in severe slurry conditions. The in-house erosion prediction library E-CODE, developed within the authors’ research group and illustrated in previous works, was employed to model the complex phenomena occurring in the valve. The good agreement between the numerical estimates and the outcomes of a test performed in the Hydraulic Laboratory of Politecnico di Milano indicated that, given the composition of the slurry environment and the operation condition of the valve, it is possible to estimate with reasonable accuracy the erosion characteristics of the device. This will allow gathering useful information for improving the scheduled maintenance of the production systems and the design of heavy-duty equipment.