Gas exploration wells are being drilled in high pressure and temperature environments targeting low permeability and high fracture gradient formations that push the envelope of conventionally used technologies. Thus, conventional perforating techniques are often not sufficient to break down the formation during fracturing operations in this type of wells.

A novel system, specially designed to enable hydraulic fracturing in challenging producers was successfully field-tested. The system includes an anchor, a multi-cycle incrementing and stroking tool (MCIST), and a jetting sub with multiple nozzles. The anchor is used to prevent axial motion of the jetting head while jet cutting, which overcomes the long-standing problem of tubing stretch due to pressure changes and vibration during abrasive perforating operations. With the anchor as a depth reference base, the MCIST changes length upon command from the surface and uses sequential jetting to create a series of evenly spaced perforations in the casing, with corresponding large diameter longitudinal slots in the formation, in a controlled and evenly spaced fashion. The tool design and testing process, details about the field trial experience as part of a stimulation treatment, and the excellent post-stimulation results achieved are discussed in the paper.

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