INNOVATION DRIVES PERFORMANCE
Originally introduced in 1998 as an environmentally appropriate alternative to synthetic-based systems to provide high penetration rates, lubricity, wellbore inhibition, and production zone protection, this high-performance water-based drilling fluid system achieves wellbore stabilization and other performance capabilities via the incorporation of its two central ingredients. Methyl glucoside and chemically active polyglycerols attach to clay/shale surfaces, thus impeding water movement into the shale under downhole conditions. These complex polyols represent a step beyond traditional glycol drilling fluids chemistry.
The beneficial hydroxyl groups contained in polyglycerol and methyl glucoside are more numerous than those provided by polyglycols. Additionally, the complex nature of the methyl glucoside molecule is considerably more effective in sealing pores than simple polyols. This molecular configuration also tends to prevent damaging penetration of the material into shale adjacent to the wellbore.
The increased availability of hydroxyls promotes development of a strong bond with shale surfaces and pore throats. This mechanism, achieved through the coupling of various polyglycerols and methyl glucoside in the system’s formulation, provides a molecular particle size distribution that effectively coats or films the wellbore, preventing water migration into the shale, while also preventing wetting and clay-particle migration.
The system also exhibits tolerance to common drilling contaminants such as salt, anhydrite and water flows; and its inherent characteristics make it a viable choice for drilling depleted sands or sub-salt environments. Further, its water-based formulation provides superior electric log interpretation; and return permeability test results indicate the system to be protective of production zones.
DeepDrill® System Eliminates Losses, Improves Logging in Deepwater Gulf of Mexico
An operator planned to drill a well in Green Canyon 82. On previous wells in that block, the operator experienced significant losses of synthetic-based fluid in the intermediate section. The current well plan included an extensive formation evaluation program at total depth, which would necessitate leaving the wellbore exposed for several days while logging and coring.
HPWBM Inhibits Shale, Offshore Mediterranean Sea
While drilling directionally through a highly reactive shale with a conventional KCl-Polymer drilling fluid, an operator encountered hole stability issues, including sloughing shale, stuck pipe, lost bottom hole assemblies and difficulty running casing. Newpark proposed the DeepDrill high-performance water-based system because of its proven history of inhibiting and protecting even the most reactive shales.
DeepDrill System Combats Ballooning and Losses
While drilling a slim hole in the deepwater Gulf of Mexico with a synthetic-based drilling fluid, an operator encountered lost circulation and formation ballooning. Newpark recommended the DeepDrill high-performance water-based drilling fluid. As a water-based solution, the DeepDrill system presented an advantage over non-aqueous fluids in that its brine base-fluid has minimal compressibility in comparison to non-aqueous fluids.
Challenge: Gas Hydrates
Gas hydrates are a crystalline combination of water and methane that form under the temperature and pressure conditions of the seafloor in deepwater environments. The crystalline structures form ice-like plugs that can block the choke or kill lines and interfere with blowout preventers (BOP’s), especially in well control situations or extended trips out of the hole.
Feature & Benefits:
Consistently lower ECDs compared with more compressible SBM base oils
Superior Shale Inhibition
Osmotic membrane development and activity control to protect the wellbore
Desirable Rheological Profile
Less subject to elevated cold-water viscosity than standard SBMs
Versatile components offer a wide range of applications in harshest environments
Gas Hydrate Suppression
Supplemental salinity and non-ionic polyol technology combat the formation of gas hydrates thermodynamically and kinetically
Best Log Interpretation
Water-based formulation enhances formation evaluation capability
- Provides benefits of an oil-based fluid in an environmentally safe water-based fluid
- Provides borehole stability
- May be used as an additive or the basis for the system
- Proprietary lubricity additive also inhibits hydration of water-sensitive shales
- Cost effective concentrations (3-4% for lubricity; 4-5% for shale inhibition)
- Environmentally safe; 100% water soluble
- Pure humalite-based fluid conditioner
- Outperforms lignite products for rheology and fluid loss control
- Extremely salt tolerant and temperature stable
- Innovative shale stabilizer
- Seals micro-fractures in shale
- Ensures cuttings integrity at low concentrations
- Prevents solids build-up resulting from cuttings dispersion
- Rapidly soluble high purity powder