PAC for Drilling Fluids: Types and Benefits

July 16, 2025
8:36 AM

In oil and gas drilling, maintaining wellbore stability, controlling fluid loss, and improving mud properties are essential to operational success. PAC (Polyanionic Cellulose) is a vital ingredient that contributes significantly to meeting these goals. Widely used across oilfield applications, PAC for drilling fluids offers a proven solution for enhancing the performance of water-based mud (WBM) systems in both onshore and offshore drilling.

This article explains what PAC is, the difference between PAC-LV and PAC-HV, and how to choose the right type of PAC in oilfield operations.

I. What Is PAC in Oilfield Drilling?

PAC (Polyanionic Cellulose) is a water-soluble cellulose ether derivative used as a filtration reducer, viscosity modifier, and wellbore stabilizer in drilling fluids. It performs efficiently in freshwater, seawater, and brine-based mud systems, offering excellent salt tolerance and thermal stability.

The value of PAC for drilling fluids lies in:

Reducing fluid loss into permeable formations

Improving rheological properties of mud

Preventing wellbore collapse

Enhancing cuttings transport efficiency

Whether you’re drilling vertical wells or high-angle deviated sections, PAC supports both cost-effective drilling and formation protection.

II. PAC-LV vs PAC-HV: Key Differences

PAC comes in two grades, PAC-LV (Low Viscosity) and PAC-HV (High Viscosity), which are intended to meet the requirements of various drilling fluid systems.

1.PAC-LV (Low Viscosity)

Designed for filtration control with minimal viscosity contribution.

Ideal for high-penetration rate drilling and low-solids systems.

Commonly used in completion fluids or reservoir drilling fluids where minimal formation damage is critical.

2.PAC-HV (High Viscosity)

Provides both fluid loss reduction and viscosity enhancement.

Improves cuttings transport and wellbore cleaning in deep or directional wells.

Suitable for challenging formations requiring strong suspension and stabilization.

Use PAC-LV when you need superior fluid loss control without thickening the mud, and PAC-HV when viscosity and suspension properties are equally important.

III. Application Benefits of PAC for Drilling Fluids

PAC has many advantages in oil drilling:

1. Superior filtrate control

PAC forms a thin, tough, and flexible filter cake on the wellbore wall, effectively sealing the permeable layer and minimizing fluid intrusion.

2. Enhanced rheology management

PAC-HV helps maintain excellent drilling fluid viscosity and gel strength, promoting effective suspension and transportation of cuttings, particularly in high-displacement wells.

3. Heat and salt resistance

PAC-LV and PAC-HV perform well under high salinity and high-temperature conditions, making them suitable for deep wells and offshore environments.

4. Environmentally friendly

Non-toxic and biodegradable, meeting environmental standards for onshore and offshore drilling operations.

IV. How TENESSY^TM PAC Compares to Other Brands?

TENESSY^TM PAC for drilling fluids is designed to match or exceed the performance of top international brands widely used in the oilfield industry. Many oil and gas service companies rely on high-cost PAC products from well-known suppliers. However, our customers have found that TENESSY PAC offers comparable quality, greater procurement flexibility, and higher cost-effectiveness without compromising performance.

1. Equivalent quality, Better value

Our PAC-LV and PAC-HV grades meet API 13A specifications for reliable performance in high salinity and high temperature drilling conditions. They are suitable as equivalent replacements for market-leading PAC products, offering the same level of filtration control, thermal stability and system compatibility.

2. High purity, fast dissolvability

We produce PAC with high purity and excellent solubility to ensure rapid hydration without residue.TENESSY^TM PAC are well dispersed and seamlessly integrate into freshwater, seawater and brine drilling systems.

3. Customized services for specific field needs

While some global suppliers only offer standard-grade PAC, we provide formulation support and viscosity customization services to suit various geological formations and drilling fluid systems. Whether your project requires a high-viscosity PAC for deep wells or a low-viscosity PAC for reservoir drilling, we can provide tailored solutions and ensure consistent batch quality.

4. Trusted by oilfield customers worldwide

Many of our oilfield customers have successfully switched from expensive international brands to our PAC products, and appreciate not only our equivalent technology, but also our responsive service, reliable logistics, and flexible delivery terms.

TENESSY^TMPAC-HV is widely used as a high-performance alternative to Ashland AquaPAC^TM, providing excellent loss-in-filtration control and rheological support through a more competitive supply solution.

V. Why Choose Our PAC for Oilfield Drilling?

As a leading PAC Supplier, we offer both PAC-LV and PAC-HV grades with:

Consistent quality and performance across batches.

Compatibility with freshwater, seawater, and brine systems.

Strong R&D support for customized formulation.

Global supply capacity with flexible packaging options (25kg bags or jumbo bags).

TENESSY^TM PAC is trusted by drilling service companies and oilfield operators worldwide to support safe, stable, and cost-effective drilling operations.

VI. Related Additives for Oilfield Drilling Applications

Although PAC remains the core additive in modern water-based drilling fluid systems, it is often combined with several other cellulose-based and polymer additives to achieve optimal drilling performance.

As a professional supplier of oilfield chemical solutions, we offer a comprehensive product portfolio to meet a wide range of drilling and completion requirements.

1.CMC (sodium carboxymethyl cellulose)

In oilfield drilling, CMC-Na is widely used as an economical and efficient loss reducer and viscosity regulator. Together with PAC, it improves the rheological control and loss-reduction capabilities of brine mud and fresh water.

2.HEC (hydroxyethyl cellulose)

HEC is utilized as a thickening and suspending ingredient in workover fluids, isolation fluids, and cementing operations. It exhibits excellent shear thinning properties and fluid stability under various pH and salinity conditions.

In drilling environments, loss control and lubricity are critical, and HEC can be used as a supplementary additive to PAC or CMC.

3.RDP (redispersible polymer powder)

Although RDP is more commonly used in the construction industry, it is also increasingly being used in specialized oilfield applications such as leak sealants, cementing mud, and wellbore sealing materials.

Its strong adhesion, flexibility, and film-forming capabilities enhance wellbore stability and formation isolation, especially in leak zones.

VII.Conclusion

PAC for drilling fluids is a vital additive in modern oilfield operations, offering exceptional control over fluid loss, improving mud rheology, and maintaining wellbore stability in various drilling conditions. Understanding the differences between PAC-LV and PAC-HV allows operators to select the right grade for their specific needs—whether minimizing filtration without thickening or boosting viscosity for better suspension and cleaning.

As a trusted PAC supplier, we offer high-purity, API-compliant products that perform reliably even in high-salinity and high-temperature environments. In addition to PAC, we also supply compatible oilfield additives such as CMC, HEC, and RDP, providing integrated chemical solutions for drilling, completion, and cementing systems.

Partner with us to improve your drilling efficiency, reduce operational risk, and streamline your supply chain with consistent, high-performance oilfield chemicals.