Viscometer State-of-the-Art - Schlumberger · Oscillating Piston Viscometer Technology ... Researchers report repeatable gas results ... Viscometer State-of-the-Art

© 2010 Cambridge Viscosity, Inc

Viscometer State-of-the-Art

Robert Kasameyer Dan Airey Jon Cole

January 22, 2010


Agenda

•  Comparison of commercially available high-pressure viscometers

•  Operating characteristics of a premier instrument: VISCOlab PVT

•  Development directions at Cambridge Viscosity

•  Need to extend viscosity standards for pressure and temperature

But first, a brief introduction to Cambridge Viscosity….


Cambridge Viscosity History

Founded in 1984 as Cambridge Applied Systems

Cambridge Viscosity since 2006 to emphasize our core business

Developed first high-pressure viscometer for reservoir fluids in 1990

Technology leader in viscosity

Thousands of installations worldwide

Process and lab viscometers

Compliance with ASTM D7483-08


Comparison of Commercial Alternatives

Rolling ball Capillary Oscillating piston/ electromagnetic viscometer

Vibrational


Capabilities of Commercial Alternatives

Oscillating Piston Capillary Tubes Rolling Ball Vibrational Accuracy ±1% † ± 1%‡ ±1–2%‡ na§

Sample per test 5 mL 25–100 mL 500 mL + 50 mL+ Max. pressure rating 20,000 psi †† 15,000 psi 10,000 psi Atmospheric

Mercury free Yes No Yes Yes Clean in place Yes No No No

Measures gas viscosity Yes No No No

Temperature range –20 to 190 degC †† Elevated only‡‡ Elevated only‡‡ –40 to 150 degC

†Published literature: ± 1–3% ‡Informal user survey: ± 5–15% §Not applicable † †Elevated options are now available ‡ ‡Baths may be available

Source: Available Published Information


Oscillating Piston Viscometer Technology

•  Piston motion is a function of acceleration, velocity, and displacement forces.

Of these, velocity dominates.

•  Velocity is determined by the piston’s drag due to shape and the fluid dynamic viscosity.

The force due to piston wall overwhelms other drags.

•  This simplifies the calculation of dynamic viscosity to

µ = f{(piston travel length)×(gap : piston to chamber2)×(travel time)}.

Sensor Shown in Process Line

Piston

Line fluid

Coils

Temp sensor

Sensor


VISCOlab PVT Viscometer Overview

Pressure transducer

Isothermal control with sensor, bath, and encasing blanket

High-pressure viscosity sensor

Key system characteristics •  Integrated sensors

•  Fully enclosed system for temperature control

•  Minimum sample volume

•  Repeatable by design

•  Easy piston range changing

• Viscosity • Temperature • Pressure


VISCOlab PVT Single Integrating Interface

On-screen statistical analysis of test conditions

Traceable pressure and temperature (PCV) compensation

Single-click temperature set

User-configurable dashboard and automatic storage of test data


Cambridge Development Directions

Recent sensor enhancements

•  Easy piston change with low-torque sealing system

•  Optional flow-through attachment for oven-based systems

Recent system developments

•  Extended pressure and temperature capabilities •  Improved gas capabilities


Recent Enhancements for Current Sensors

Easy piston change with low-torque sealing system

Flow-through attachment for oven-based systems


Extend Instrument’s Temperature and Pressure Capability

Temperature, degC

Pressure, psi

40,000

20,000

190  300

Currently available

option

Currently available

option

Standard Cambridge product

Not yet available


Expand Gas Capabilities

•  2001: Initial proof of concept to extend to gas range (0.02–0.2 cP)

•  2005: Supported industry requests to extend availability

•  2008: CVI began calibrating gas range with N.4 (Hexane) and CO2

•  2009: Researchers report repeatable gas results •  University of Calgary, IPN, Clemson, Aramco

•  Next steps: •  Extend industry findings


Pressure and Temperature Standards •  Instrument calibration is necessary.

• Critical sensor feature: annular space between piston and chamber wall

• Space to increase with temperature and/or pressure •  Compensation factor based on

• Published data on fluids characterized by NIST and others

• Data to 20,000 psi and 150 degC, depending on the fluid and test, but limited by viscosity, temperature, and pressure.

•  Compensation is based on best-fit correlations for • Temperature and pressure (linear)

• Each piston range.

Fluid standards for extended pressures and temperatures are needed.


Traceable References >2 cP Lacking Above 10,000 psi

0

5

10

15

20

25

30

35

40

0 5000 10000 15000 20000 25000 30000 35000 40000 45000

Visc

osity

, cP

Pressure, psi

High-Pressure, High-Viscosity Measurements with Oscillating Piston Viscometer

Dodecane at 25C NIST dodecane at 25C S6 at 25C S6 at 100C"

Characterization of NIST- traceable references boxed in red area VISCOlab PVT measurements for Dodecane and S6


Summary: Viscometer State-of-the-Art

•  Developed to meet industry requirements for: •  Accuracy

•  Small sample size

•  Pressure and temperature

•  Ease of use

•  Continued enhancements for developing industry needs

•  The lack of appropriate viscosity reference standards is becoming a more acute problem as pressure and temperature requirements increase.

VISCOlab PVT:

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Viscometer State-of-the-Art - Schlumberger · Oscillating Piston Viscometer Technology ... Researchers report repeatable gas results ... Viscometer State-of-the-Art