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Designing limited-entry fracture completions for horizontal wells

Many completion techniques have been used for fracture stimulation of horizontal wells. Multiple-stage fracturing treatments are highly effective, but carry high cost and risk that often make it unattractive. Limited-entry fracturing (LEF) has proven to be an effective stimulation method for horizontal wells with an acceptable level of cost and risk. LIMITED-ENTRY FRACTURING LEF uses perforation friction pressure to control the stimulation fluid distribution into each perforated interval and has been used successfully for years in vertical wells. In horizontal wells, several LEF characteristics include: • Fluid friction along the tubulars in long intervals • Little or no hydrostatic pressure changes along the lateral • Perforation erosion by proppant slurries.1 Pipe friction in very long horizontal completions is often the limiting factor when determining the maximum treating rate. Perforation erosion, which only has a minor effect on fluid distribution in vertical wells, can significantly affect the fluid distribution in horizontal stimulation treatments.