AquaPac

Improve openhole gravel packs with an integrated completion approach

AquaPac openhole gravel-pack service uses brine to carry and place gravel around preinstalled screens. It successfully addresses the challenges presented by many highly deviated openhole wells: low fracture gradients, reactive shales, and unstable boreholes. The entire process—design, execution, and evaluation—is supported by proprietary software to identify the optimal treatment options for your well.

Three-prong strategy for low-fracture-gradient formations

Gravel is conventionally placed in two waves. During the alpha wave, the gravel dune migrates evenly downward along the lower part of the well. When the toe is packed, pressure increases as the beta wave carries the dune back toward the heel to fill the top part of the wellbore. In low-fracture-gradient formations, this increased pressure can cause the formation to fracture. The resulting fluid losses can trigger the creation of a gravel bridge that disrupts the beta wave and leaves sections of the screens unpacked.

To combat the risk of inadvertently fracturing the formation, the AquaPac service reduces friction pressure by using

• pressure attenuators—multiple pressure-activated diverter valves along the washpipe to reduce the length of washpipe through which the returning gravel-pack carrier fluid must flow
• a friction reducer pumped in the carrier fluid
• lightweight gravels that can be transported at lower flow rates.

Shale stabilizer to minimize fluid reactions and formation damage

Water-based fluids can cause shale to quickly swell, deteriorate, or both, resulting in an unstable wellbore that can collapse or cause incomplete gravel packing. Water-induced spalling, or breaking up, of the shale can also cause premature screenout, impair pack porosity and permeability, or plug the screen, blocking production. The AquaPac service uses a shale stabilizer to inhibit these destructive brine-shale interactions.

Fluid for wells drilled with oil-based mud

PrimoPAC invert-emulsion gravel-pack carrier fluid mitigates risks when transitioning from a synthetic- or oil-based drill-in fluid to a brine-based carrier fluid and spacer for openhole gravel-pack completions in reactive shales. This unique fluid helps prevent crossfluid compatibility issues and eliminates shale stability and dispersion issues, resulting in less rig time, lower fluid costs, and preserved assets.

Antiswab service tool—multiple benefits in a single trip

Stabilization of an unconsolidated sandface is vital to gravel-pack success. The Schlumberger antiswab service tool permits constant hydrostatic pressure in the open hole, eliminating the swabbing effects of hardware movement and ensuring filtercake integrity before gravel placement. The tool also isolates the packer-setting mechanism to prevent presetting caused by circulating pressures. After the excess gravel is screened out and reversed, the service tool allows spotting of filtercake removal treatments, eliminating a dedicated cleanup run.

Filtercake removal for faster, more efficient cleanup

MUDSOLV NG integrated filtercake removal service is used to tailor the most effective cleanup strategy. The goal is to minimize screen plugging, impaired well performance, hardware-damaging hot spots, and corrosion.