High-density oil-based drilling fluid is a specialized drilling fluid system designed to tackle extreme drilling conditions. By adding weighting materials such as barite (barium sulfate) and iron ore powder to conventional oil-based drilling fluids, the density of the drilling fluid can be increased. High-density oil-based drilling fluids play a crucial role in drilling high-pressure oil and gas reservoirs, deepwater drilling, and situations that require pressure balance to prevent blowouts.

Features

1.    High Density: By adding weighting materials, the density of the drilling fluid can be easily adjusted to the required range, effectively balancing formation pressure, with a maximum density of up to 2.67 g/cm³.

2.    Good Rheology: Even in a high-density state, the drilling fluid maintains stable rheological properties, ensuring effective cuttings transport and suspension.

3.    Emulsion Stability: Advanced emulsification technology and stabilizers ensure that the oil-water phases maintain a stable emulsified structure during long-term circulation.

4.    Strong Contamination Resistance: The drilling fluid exhibits high resistance to contaminants such as salts, calcium, and cuttings that may be encountered during drilling.

5.    High-Temperature Stability: In high-temperature environments, high-density oil-based drilling fluids can maintain good performance, meeting the demands of high-temperature deep well drilling.

Advantages

1.    Increased Drilling Safety: By balancing formation pressure, the occurrence of blowouts and other safety incidents is reduced.

2.    Enhanced Wellbore Stability: High-density drilling fluids provide better support, reducing the risk of wellbore collapse.

3.    Improved Drilling Efficiency: Good rheological and lubricating properties help to reduce drilling resistance, increasing penetration rates and footage.

4.    Strong Adaptability: Suitable for various complex formations and extreme drilling conditions, such as deepwater drilling and ultra-deep wells.

5.    Environmental Performance: Compared to water-based drilling fluids, high-density oil-based drilling fluids have a relatively lower environmental impact in case of leakage.

Applications

1.    High-Pressure Oil and Gas Reservoir Drilling: In high-pressure oil and gas reservoirs, high-density drilling fluids effectively balance formation pressure and prevent blowouts and other safety incidents.

2.    Deepwater Drilling: As water depth increases during deepwater drilling, formation pressure gradually increases, making high-density drilling fluids essential.

3.    Ultra-Deep Well Drilling: In ultra-deep well drilling, due to extremely high formation pressure and various complex geological conditions, high-density drilling fluids provide a stable drilling environment.

4.    Complex Formation Drilling: In formations prone to collapse and leakage, high-density drilling fluids offer better support and anti-collapse effects, ensuring smooth drilling operations.

In summary, high-density oil-based drilling fluids play a vital role in drilling high-pressure oil and gas reservoirs, deepwater drilling, and situations that require balancing formation pressure to prevent blowouts.

System Supporting Additives

JHEMUL Main Emulsifier

JHCOAT Auxiliary Emulsifier

JHWET Wetting Agent

Key Additive JHEMUL Main Emulsifier Introduction

JHEMUL main emulsifier is a surfactant specifically designed for oil-based drilling fluids. It can form a stable molecular film between the oil and water phases through chemical means, significantly reducing the interfacial tension between the two phases and enhancing the emulsification effect.

Functions

1.    Thickening Effect: JHEMUL main emulsifier can effectively disperse water in the oil phase, increasing the viscosity of the liquid phase and improving the flow and lubricating properties of the drilling fluid.

2.    Dispersion Lubrication: This emulsifier can disperse solid particles in the liquid phase, reducing the interaction forces between particles, lowering friction resistance, and enhancing drilling efficiency.

3.    Foam Reduction: By inhibiting foam formation in the drilling fluid, it reduces the likelihood of flooding in the wellbore.

4.    Stabilization of Liquid Phase: Enhances the stability of the liquid phase and reduces the possibility of phase separation, thereby lowering the incidence of drilling accidents.

Applicable Range

1.    Temperature: Generally, this emulsifier can maintain stable emulsification effects in high-temperature environments, meeting drilling operation needs.

2.    System: Suitable for the GAWADRIL high-density oil-based drilling fluid system.

Key Additive JHCOAT Auxiliary Emulsifier Introduction

JHCOAT auxiliary emulsifier is a surfactant designed specifically for high-density oil-based drilling fluids, aimed at working in synergy with the main emulsifier to form a more stable and high-performance drilling fluid system. This auxiliary emulsifier typically has a specific molecular structure and chemical properties, allowing it to form a robust interfacial film between the oil and water phases, thereby enhancing emulsification and improving the overall performance of the drilling fluid.

Functions

1.    Enhance Emulsion Stability: JHCOAT auxiliary emulsifier can increase the stability of the oil-in-water emulsion in the drilling fluid, preventing demulsification or phase separation under harsh conditions such as high temperature and pressure.

2.    Enhance Temperature Resistance: This auxiliary emulsifier has excellent temperature resistance, enabling the drilling fluid to maintain stability and emulsification effects in high-temperature environments.

3.    Improve Lubrication: By optimizing the lubrication properties of the drilling fluid, JHCOAT auxiliary emulsifier can reduce friction resistance and torque during drilling, enhancing drilling efficiency.

4.    Reduce Drilling Accidents: A stable emulsion and excellent lubricating properties help reduce the incidence of drilling accidents, such as wellbore collapse and sticking.

Applicable Range

1.    Temperature: Exhibits excellent temperature resistance, maintaining stability and emulsification effects of the drilling fluid under high temperature and pressure.

2.    System: Suitable for the GAWADRIL high-density oil-based drilling fluid system.

Case Studies

This system has been successfully applied in over 200 wells in the Sichuan-Chongqing block, where the high-density drilling fluid exhibits high viscosity and shear strength, effectively suppressing the invasion of formation fluids into the wellbore while protecting the oil and gas layers from contamination.

In the Luzhou area of the Sichuan Basin, where the geothermal gradient and formation pressure coefficient are high, the application of high-density drilling fluids has shown good temperature resistance and stable contamination resistance, maintaining good rheological performance even at densities exceeding 2.25 g/cm³.

In the Yang 101H33-4 well, drilling reached a depth of 6690 m, with a penetration of 3914 m using high-density oil-based drilling fluids, and a horizontal section of 2200 m over a drilling cycle of 44.6 days. The wellbore remained stable during drilling, with no occurrences of blockages, sticking, or well leakage. When encountering the high-pressure gas layer in the Shiniulan formation, the density reached 2.30 g/cm³ while still maintaining good rheological stability and strong resistance to cuttings contamination. The drilling process experienced low friction during tripping, and logging, and casing operations were smooth, demonstrating high protective performance for the production layer.