Optimum Design Of Construction Parameters Of High Pressure Gravel Packing

Sand production is a popular problem during developing loose sand reservoirs, and seriously restricts the maintenance and increase of production. In order to ensure the normal production, some sand control measures must be taken, one of which is high pressure gravel packing. The construction parameters are determined by combination of some relative frac-packing data and engineering experience, as leads to an obvious difference between the designed values and the actual values, especially the packed sand amount outside casing.Mechanical parameters of loose sand reservoir is very important for construction parameters design of high pressure gravel packing. Based on some related literatures, a method to calculate the mechanical parameters such as elastic modulus, possion's ratio, tensile strength and compressive strength, was developed. Compared with laboratory experiment, it had the advantage of low cost and convenient operation.Employing the cylindrical cavity expansion model used in geotechnical engineering, a preliminary study on the configuration of near well-bore area was performed. Considering the significant difference between the actual condition of stratum and cylindrical cavity expansion model, a model to predict the packed sand amount outside casing based on logging data was established by further analysis. Based on the construction data of some oil wells on which high pressure gravel packing was put, two fitting curves to prediction packed sand amount were achieved. By the error analysis of the model, this model had high calculation precision and good guiding significance.Consulting some related references, the method to calculate construction parameters such as gravel size, critical displacement, sand ratio, screen pipe size, was determined. In addition, the influence of sand control on productivity was studied. For convenient practical application and high work efficiency, a software to design construction parameters of high pressure gravel packing was developed by Visual Basic programming language. This software can calculate mechanical parameters such as elastic modulus by logging data, predict packed sand amount outside casing based on logging data, and analyze the influence of high pressure gravel packing on productivity.