When well fluid is produced from a subterranean formation, the fluid typically contains particulates, or “sand.”  The production of sand from the well typically is controlled for such purposes as preventing erosion and protecting upstream equipment.  One way to control sand production is to install sand screens in the well to filter sand from the produced well fluid.  Various types of sand screens may be used, such as a sand screen that is formed from a cylindrical mesh or a sand screen that is formed by wrapping wire in a helical pattern. 
The sand screen may be part of a larger sand screen assembly.  In addition to one or multiple sand screens, the sand screen assembly may include a base pipe that forms part of a tubing string and one or more inflow control devices (ICDs), which regulate the flow of the produced well fluid into the interior space of the base pipe.