OFITE Model 170-95-1 High-Temperature High-Pressure Dynamic Filtration Tester

Overview

The OFITE Model 170-95-1 High-Temperature High-Pressure Dynamic Filtration Tester is an engineered laboratory instrument designed to replicate downhole drilling fluid filtration behavior under realistic dynamic flow conditions. Unlike static HPHT filtration devices, this system introduces controlled shear through a motor-driven impeller within a sealed 500 mL pressure vessel—enabling quantitative assessment of fluid loss volume, filter cake formation kinetics, and cake integrity across a wide operational envelope. The device operates on the principle of forced radial or axial flow across a planar filtration medium, where fluid velocity, shear rate, and differential pressure are independently adjustable. This architecture supports direct correlation with field-scale filtration mechanisms observed in deviated and horizontal wells, where annular flow dynamics significantly influence mudcake development and permeability.

Key Features

• Motor-driven impeller with continuously variable speed control (1–3600 rpm), enabling precise shear rate modulation from laminar to turbulent regimes
• Adjustable impeller-to-filter-medium standoff distance, allowing systematic investigation of near-wall shear effects on cake morphology
• Dual-flow impeller options: radial-blade configuration for high-shear radial dispersion; axial-blade design for uniform axial velocity profiles
• Integrated water-cooling circuit for rapid post-test depressurization and safe sample retrieval at elevated temperatures (up to 260 °C)
• Digital PID temperature controller with ±1 °C stability over full range; calibrated platinum RTD sensor embedded in vessel wall
• Modular filtration base assembly accommodating standardized 76 mm diameter discs—including porous ceramic, sintered stainless steel, graded sand packs, and ASTM D1386-compliant filter paper
• Calibrated rupture disc (burst pressure: 34.5 MPa ±2%) compliant with ASME BPVC Section VIII Div. 1 safety requirements
• Integrated back-pressure regulator and auxiliary port on top cap for in-situ additive injection or pressure monitoring

Sample Compatibility & Compliance

The 170-95-1 accommodates aqueous and oil-based drilling fluids, synthetic-based muds (SBMs), and engineered nanofluids containing polymers, viscosifiers, or bridging agents. Its filtration geometry conforms to API RP 13B-1 and ISO 10414-2 methodology frameworks for dynamic filtration testing. All wetted components—including the Hastelloy C-276 pressure vessel, Inconel 718 impeller shaft, and fluoropolymer-sealed fittings—meet NACE MR0175/ISO 15156 requirements for sour service environments. The system supports GLP-compliant operation when paired with audit-trail-enabled data acquisition software, satisfying traceability requirements under 21 CFR Part 11 for regulated R&D laboratories.

Software & Data Management

While the base unit operates via front-panel digital controls, optional OFITE DataLink™ software provides synchronized logging of temperature, pressure, rotational speed, filtrate volume (via gravimetric or volumetric transducer), and time-stamped event markers. Data export is native to CSV and Excel-compatible formats, with metadata fields supporting ISO/IEC 17025-compliant reporting. Calibration certificates for all sensors (pressure transducer, RTD, flow meter) are supplied with NIST-traceable documentation. Firmware updates maintain alignment with evolving industry test protocols, including recent revisions to IADC Drilling Fluids Manual Chapter 5.

Applications

• Quantifying dynamic fluid loss coefficients (α and β) for rheologically complex mud systems under simulated wellbore shear profiles
• Evaluating low-permeability filter cake formation in ultra-deepwater HPHT wells (e.g., Gulf of Mexico, Santos Basin)
• Screening nano-additives (e.g., graphene oxide, cellulose nanocrystals) for cake-enhancing functionality under oscillatory shear
• Validating filtration models used in commercial wellbore stability simulators (e.g., PETREL, Drillbench)
• Supporting regulatory submissions for novel mud formulations under EPA NPDES or OSPAR Commission guidelines
• Conducting comparative studies between static and dynamic filtration outcomes per API RP 13I Annex B

FAQ

What filtration media are compatible with the 170-95-1?
Standardized 76 mm diameter discs including ASTM D1386 Grade 1 filter paper, porous ceramic (1–5 µm pore size), sintered stainless steel (5–50 µm), and custom-packed sand columns.
Is the system suitable for H₂S-containing fluids?
Yes—the pressure vessel, seals, and internal components are certified to NACE MR0175/ISO 15156 for sour service up to 260 °C and 34.5 MPa.
How is shear rate calculated during testing?
Shear rate is derived from impeller tip speed and gap height using Couette flow approximation; validated experimentally via PIV calibration for each impeller geometry.
Does the unit support automated data acquisition?
Optional OFITE DataLink™ software enables real-time parameter logging, configurable alarms, and electronic signature-capable report generation compliant with 21 CFR Part 11.
What maintenance intervals are recommended?
Quarterly verification of burst disc calibration, annual pressure transducer recalibration, and biannual inspection of O-ring integrity per OFITE Maintenance Protocol MP-170-95-1 Rev. D.