Over 500 field applications have been made with a sand control process which achieves gravel packing and sand consolidation in essentially one treating step. It was designed to improve conventional gravel packing and yet offer advantages over sand control achieved by gravel packing followed by sand consolidation techniques.
In a related application, successful repair of damaged areas in wire-wrapped screens or slotted liners in place has been accomplished with this method. This has eliminated the expense of pulling and repairing or replacing the screening device and then repacking.
The application of the resin-sand pack method of sand control results in a strong, highly permeable filter around the wellbore. In addition, a portion of the formation sand may be consolidated with the treatment, resulting in an effective screen for preventing formation fines from entering the preventing formation fines from entering the pack sand and acting as a possible deterrent pack sand and acting as a possible deterrent to production declines which frequently follow gravel packs. The consolidated pack sand offers additional strength over gravel packs to withstand overburden and other stresses. This will tend to lessen damage to casing and cement jobs. Also, in conventional perforated casing completion treatments, perforated casing completion treatments, mechanical screening devices are generally not needed.
The method described uses selected pack sand coated by a small quantity of furfuryl alcohol resin finely dispersed in a low viscosity oil. This provides for all the pack sand's being resin-coated. This method pack sand's being resin-coated. This method is generally more economical than gravel packs followed by consolidation techniques since the latter method normally requires more resin to coat all the gravel pack solids. Low pump rates may be used to minimize damage to the formation. The resin can be externally or internally catalyzed, a feature which allows flexibility of this method for use in perforated casing completions, around liners perforated casing completions, around liners in casing or open hole, or for repairing holes in old gravel screens or liners.
