This system is designed to evaluate the rheological properties of completion and
fracturing fluids. This is carried out by mixing the completion fluid or fracture
gel in the paddle stirrer tanks and then pumping a through a heated shear loop to
condition the fluid and simulate down hole conditions. The fluid/slurry is then
pumped though a series of pipes to measure the shear stress exhibited by the fluid/slurry
at different shear rates. Using this shear stress vs. shear rate data the rheological
properties of the slurry can be determined (n’, k’, apparent viscosity). Following
the determination of the rheological properties with the Pipe Rheometer, the fluid/slurry
is then either disposed of or used in ancillary experiments. After measurement in
the system the exiting fluid can be returned to the mixing tanks or used in experiments
in the RPTA or AFCS systems.
Mixing System – comprising 50 gallon lidded plastic tank complete
with centrifugal feed pump, paddle stirrer and associated tubing, valves and fittings.
Pumping System - comprising a Primary Pressure Pump fed by the
Mixing System Pump a Cross Linking pump allows introduction of the cross linking
agent to the fluid exiting the Primary Pump. The Pressure Pump can deliver gel at
up to 1,000 ml per minute and a maximum pressure of 4,800 psi. The Cross Linking
Pump injects fluid at a variable rate of 5 ml per minute up to 120 ml per minute.
Heated Well Bore Shear Rate Simulator - to simulate high shear
well bore environment and to raise fluid temperature from ambient to a maximum of
300 °F. A shear rate of 1,500 reciprocal seconds has been selected to represent the
most common rate seen in operations however customized shear loops are available
as a factory installed option. The length of the shear loop can be manually adjusted
to allow variable residence times of 1 minute, 2.5 minutes or 5 minutes.
Heated Fracture shear Simulator – to simulate the shear forces a completion fluid
would experience as it progresses down the length of the fracture. To accomplish
this a shear rate of 80 reciprocal seconds has been selected as most representative of the actual reservoir conditions.
Residence time for the fluid is fixed at 5 minutes with temperature of up to 300 °F obtainable.
Modular Pipe Rheometer - comprising 4 varying diameter straight tubing with digital gage and
differential pressure transducer array. Complete with oil bath heating system to maintain system temperature.
Cooling Loop and Back Pressure System - to cool fluid to below 212 °F before exiting the
and to maintain system pressure during the rheological measurements.
Data Acquisition System - PC based system with USB 2.0 data acquisition and minimum workstation
with PC, Dual 21 inch LCD Monitors, 1GB RAM, 520GBHard Drive, CD/DVD RW with Microsoft Windows Operating System.
Custom inter-active graphics based control software allows for the control and operation of
the system whilst monitoring and recording all pressure, temperature, flow rate. On screen custom graphing of
data is accomplished through the inter-active program interface. From the flow rate, differential pressure and
the diameters and lengths of the four pipes shear stress of the fluid is calculated along with the shear rate
in each tube. The viscosity of the fluid at each shear rate is then displayed real time.
Note: Pipe Rheometers are available to cover the full range of fluids encountered in completion
and stimulation studies. A number of set ups may be required to cover the range anticipated in a particular laboratory
and can be easily substituted into the system.