Model 300 Shear History Simulator
The rheology of a fracturing fluid is highly dependent upon the composition/concentration
of the polymer and crosslinker, temperature, pH, the magnitude of shear,
and the duration of shear. To minimize parasitic frictional pressure
losses, an optimal fracturing fluid would have only sufficient viscosity
to fully transport the proppant from the well head, through the tubulars
and perforations, and into the formation. This proves difficult because
during fracturing operations, fluid temperature increases, magnitude
of shear varies, and duration of shear increases. Fortunately, the use
of delayed crosslinkers makes it possible to control the rheology of
a fracturing fluid as a function of time and/or shear. Under ideal circumstances,
the polymer would fully crosslink just before entering the perforations
of the well. A fluid of this design would minimize parasitic frictional
pressure losses within the tubular goods, while ensuring that maximum
viscosity would be achieved at the perforations of the well. This increase
in viscosity allows the fluid to effectively transport the proppant though
the perforations and into the formation. OFITE's Shear History Simulator
makes it possible to analyze the effects of shear, duration of shear,
and temperature upon a fracturing fluid and is an invaluable tool in
the optimization of fluid design.
Method of Operation:
The polymer is mixed and pumped into one of the accumulators of the
apparatus. Water, which is used to displace the test fluid, is pumped
into the other accumulator. The syringe pump is filled with the crosslinker
and the flow rate is adjusted accordingly. The temperature baths on each
of the capillary coils are adjusted to set point and allowed to reach
temperature. The flow rate of the polymer delivery pump is adjusted to
achieve the same rate of shear as that anticipated during the actual
fracturing treatment. The fluid delivery pump and crosslinker pump are
started simultaneously and the fluids are thoroughly blended via an inline
static mixer. Once the fluid is homogenized, it is pumped through either
one, two, or all three of the capillary coils depending upon the well
depth of the fracturing operation. Differential pressure and temperature
of each coil is documented on a multi-channel strip chart recorder. The
sheared fluid may then be directly injected into the rotor of an HTHP
Rheometer for further studies.
Features and Specifications:
- All wetted components manufactured from 316 SS
- Three temperature baths for custom temperature gradients
- Temperature (400°F maximum) maintained via PID controllers
- Process temperature is displayed digitally
- Temperature measured via thermocouple
- Triplex metering pump drives polymer fluid
- Syringe pump accurately delivers crosslinker
- Differential pressure transducers measure Delta P
- Multi-channel strip chart recorder provides hard copy of data
- Two 1,500 cc 316 stainless steel accumulators
- Three 75 foot, 316 stainless steel capillary coils
Instrument Requirements:
- 40 PSI 10 gpm water source
- 220 Volt, 50/60 Hz, 6 KVA power source
For more information about this product or to request a quote, contact us.
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