To minimize drilling fluid losses, pressure-induced fractures must be propped and sealed. (Image courtesy of MI-SWACO)

Historically, standard remediative treatments for stemming losses in induced fractures have not been overly successful. This is especially true if losses are recurring, such as when drilling through depleted zones or when the pore-pressure, fracture-gradient drilling windows are narrow.

M-I SWACO’s new integrated borehole strengthening solutions (I-BOSS) toolkit provides a solution for stabilizing well bores while drilling, which enables construction with low fracture gradients for significantly reduced costs.

When opting to drill near or above the fracture initiation pressure, operators have a variety of techniques available to enhance the integrity of the well bore. These include: increasing the near-wellbore strength and the fracture initiation pressure; isolating the tip of the existing fractures and increasing fracture reopening pressure; and isolating the well bore from the wellbore fluid and/or pressure. I-BOSS integrates all of these concepts and provides a means of implementing solutions.

To increase the near-wellbore strength in a permeable formation, the wellbore pressure is elevated to the level desired to drill through the formation, potentially initiating fractures. If fractures are encountered, they must be propped and sealed to minimize loss of drilling fluid.

I-BOSS uses the Opti-Stress software package to calculate a probability distribution for the induced fracture. It then calculates the necessary blend of loss prevention material (LPM) and particle-size distribution (PSD), optimizing the concentrations required for efficiently propping and sealing.

A critical component of the I-BOSS engineering solution is use of the LPM recovery system, MPSRS, which significantly improves cost effectiveness of the near-wellbore strengthening treatment.

The savings are twofold. First, drilling performance is increased because of lost circulation avoidance. Second, product consumption is reduced due to the recovery process.

I-Boss provides operators with a comprehensive package to analyze and control wellbore fracturing while significantly reducing drilling costs.