SOLID PARTICLE IMPACT EROSION TESTING OF TEXACO FILTER ELEMENTS AND SELECTED WELL COMPLETION MATERIALS

In situ heavy oil, oil sand pilots, and conventional oil production located in unconsolidated sand reservoirs, have experienced a variety of problems related to plugging, dissolution of silica sand conventional used as a filter-pack, and erosion. The erosion is followed by a massive inflow of sand into the production wells resulting in reduction of flow capacity. To alleviate some of these problems, a new metallic filter of high porosity was designed and field tested. It employed steel wool elastically compressed and sandwiched between inner and outer high-resistance mandrels. Field testing of the new filters has revealed some erosion-associated problems and a laboratory program was initiated to find the optimal design criteria for reducing the erosion damage. For the first time, the capacity of compressed metallic wool to withstand erosion was experimentally assessed. Standard sand-jet blasting equipment was calibrated and used to determine penetration time for common well-material coupons and for compressed metallic wool filters. Filters having the compression factors ranging from 5 (density = 0.15) to 30 (density = 0.92) and metallic wool depth from 6 mm to 19 mm were exposed to the erosion tests and results are presented graphically and analytically. It appears that increasing the wool density or filter thickness lead to an optimum value resulting in maximum filter erosion resistance. Photomicrographs of the eroded zones are presented in order to explain some of the mechanisms involved.