Gravel packing is one of the oldest and most useful methods for controlling loose sand in wells. This art has advanced considerably with the studies of proper gravel sizes, improvements in the manufacture and design of screens and the multitude of tools to help get the gravel in place.
A significant improvement was the pressure packing technique. By placing pressure packing technique. By placing gravel outside the casing a higher flow capacity can be expected. Radial flow equations show that productivity increases as much as 50% can be obtained. However, seldom are such good results achieved and it is rare when good productivity is maintained.
Existing gravel packing techniques and literature are aimed at trying to use the largest possible gravel size. Much thought has gone into retaining a high flow capacity but controlling the sand has been secondary. In fact, many experts claim that it is necessary that formation fines be continuously produced through a gravel pack in order to produce fluids. To do that a relatively large gravel size must be used.
We have looked at gravel packing with the idea of using the smallest possible gravel size that will not decrease the productivity of a well. It can be proven that productivity of a well. It can be proven that the use of gravel only slightly larger than the formation sand if properly placed in the well will actually increase productivity.
A new gravel placement technique has been developed and field tested using small gravel. This technique uses no special tools or equipment and can be done in a fraction of the time that many gravel packs presently use. It results in an almost presently use. It results in an almost ideal pack which gives perfect control of the formation and high production rates are retained. A unique slurry is used which departs dramatically from all known gravel packing procedures. packing procedures.