The successful application of fracturing for sand control has been reported from many different areas. Several explanations have been advocated for these successes such as "re-stressing" the wellbore, creation of a "halo effect" around the wellbore and maintaining the bottom hole pressure above a critical level to prevent perforation collapse. The latter approach has led to complex models predicting the conditions of perforation failure.
However, once the perforations have collapsed, the production of formation sand is governed by the transport of the sand from the perforation tunnels. Frequently, decreasing the production rate stops sand production, indicating that there is a critical flow rate below which sand cannot be transported into the wellbore. In this study, we present the development, application and field validation of a spreadsheet tool to improve the reliability of fracturing for sand control treatments.
A universal curve was generated from numerical simulations, showing that the percentage of the total flow through the perforations not connected to the fracture was a function of the formation and fracture properties and was independent of the reservoir fluid properties. The generation of a universal curve eliminates the need to use a reservoir simulator and allowed the development of a tool to aid the design of fracturing for sand control treatments. The spreadsheet tool has been validated with data from successful fracturing for sand control treatments.