Wire-wrapped screens, in many different design configurations, have been the industry standard for use in gravel pack completions. Lately, some of the advantages of prepack designs, have generated interest and are being used in both cased and operinole completions. Of specific interest have been prepack designs having a thinner aggregate layer which affords more annulus clearance to help assure adequate gravel placement and retreivability.
One recent development in porous sintered stainless steel technology introduces a thin-walled, sintered stainless steel screen that appears to offer improvements over prepack screens. Some advantages to the porous sintered metal screens (PSMS) over thin-wall designed prepack screens (TWPS) have been confirmed by current testing. These include uniformity of the porous metal screen media and resistance to damage due to handling.
In addition to a discussion of the above findings, the paper presente results of comparative testing of the two type screen designs for the effect of bending stresses, flow capacity, scaling tendencies, and cleanout by backflusbing. A study of the effects of brines, acids, and H2S on the porous metal is also included.
The most gravel pack screen-related failures have been traced to. impact damage and erosion cutting. The introduction of this new porous sintered metal technology to reduce screen failures can save money in reducing the number of workoveis and in prevention of production declines.