The high-performance polyamine drilling fluid system is a new type of water-based drilling fluid that has gained significant attention and application in the oil drilling industry in recent years. By incorporating polyamine compounds, this system significantly enhances the inhibition, rheological properties, and high-temperature stability of drilling fluids, thus solving many issues faced by traditional drilling fluids in complex geological conditions.

Characteristics

1. Strong Inhibition: Polyamine compounds in the drilling fluid system effectively inhibit clay hydration, swelling, and dispersion, reducing the erosion of the wellbore by drilling fluids and maintaining borehole stability.

2. Good Rheological Properties: This system maintains stable rheological behavior from low to high temperatures, meeting the needs of different drilling depths.

3. High-Temperature Stability: The polyamine drilling fluid system offers excellent thermal stability, maintaining its performance in high-temperature and high-pressure      environments.

4. Lubricity: The lubricants in the system reduce friction between the drill string and wellbore, enhancing drilling efficiency.

Advantages

1. Improved Drilling Efficiency: The  system's excellent rheological properties and lubricity reduce resistance and energy consumption during drilling, thus increasing drilling      efficiency.

2. Reduced Drilling Costs: By minimizing fluid loss and wellbore instability, the system lowers the  incidence of drilling-related accidents and maintenance costs.

3. Enhanced Borehole Stability: The polyamine system effectively inhibits clay hydration and dispersion,  maintaining borehole stability and reducing the risks of downhole      collapse.

4. Strong Adaptability: Suitable for various geological conditions, including high-temperature,  high-pressure, and water-sensitive formations.

Applications

1. Land and Offshore Oil and Gas  Drilling: Widely used in conventional and deepwater drilling,  improving borehole stability and hole cleaning efficiency.

2. Unconventional Oil and Gas  Development: Extensively adopted in shale gas and tight oil drilling due to its effective clay swelling inhibition properties.

3. Mudstone and Shale Formations: The technology effectively prevents hydration swelling in clay mineral-rich shale formations, improving wellbore stability through the use of polyamine inhibitors.

Complementary Additives

·        UHIB Polyamine Inhibitor: A cationic compound that effectively inhibits clay hydration and dispersion by adsorbing onto negatively charged clay particles and forming stable hydrogen bonds.

• HyperFREE Hole Cleaner:      Enhances wellbore cleaning and cuttings removal.

• PolyCAP Encapsulating Agent:      Improves drilling fluid stability and performance.

• PolyPAC Filtrate Reducer:      Minimizes fluid loss.

• BioLUBE Lubricant:      Reduces friction and enhances drilling efficiency.

Key Additive - UHIB Polyamine Inhibitor

UHIB polyamine is synthesized through group analysis and multi-pathway design. It dissociates in water into cationic compounds that adsorb onto clay particles, effectively inhibiting clay hydration swelling and dispersion. Its weak alkalinity and dissociation balance ensure sustained long-term inhibition, even in challenging drilling environments.

Functions:

1. Inhibit Clay Hydration:      Adsorbs onto clay surfaces to prevent water absorption and swelling.

2. Prevent Tool Corrosion:      Protects drill pipes from corrosion by acidic gases or substances.

3. Maintain Fluid Stability:      Neutralizes acids and buffers fluids to stabilize properties.

4. Long-Term Inhibition:      Provides durable formation inhibition, resisting erosive effects.

5. Synergistic Effects:      Works well with other additives for enhanced stability and performance.

Applicable Conditions:

1. Temperature:      Operates effectively up to 170°C and even 200°C in certain conditions.

2. Fluid Systems:      Suitable for water-based drilling and completion fluids, gravel packing fluids, etc.

Case Studies

BZ28-2 Block

The BZ28-2 block features complex formations with high clay content and water sensitivity, presenting significant drilling challenges due to hydration and wellbore instability. The polyamine water-based drilling fluid, notably using UHIB as the primary inhibitor, demonstrated excellent performance in stabilizing wellbores and reducing risks such as drill string entrapment and torque increase.

Advantages and Effects:

        1.Wellbore Stability: Minimizes hydration and dispersion, reducing collapse risks.

        2.Increased Drilling Efficiency: Controls torque and pump pressure, shortening drilling cycles.

        3.Cost Reduction: Lower accident rates reduce maintenance and operational costs.

        4.Environmental Benefits: Meets environmental standards with reduced pollution.

RM19 Well

Located in a geologically complex region with high-pressure and temperature gradients, the RM19 well required a robust fluid system. The polyamine water-based drilling fluid proved suitable by maintaining wellbore stability and enhancing operational efficiency under tough conditions.

Advantages and Effects:

1. Stability:      Prevented wellbore collapse and tool entrapment.

2. Efficiency:      Enhanced control over mechanical parameters increased drilling speed.

3. Cost-Effectiveness:      Reduced accident incidences and associated costs, boosting economic viability.