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The Small Sample
Adapter (SSA), consisting of a cylindrical sample chamber and
spindle, provides a defined system for accurate viscosity
measurements of small sample volumes in the order of 2 to 16 ml.
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Removable
Sample Chamber : The design of the SSA allows the sample
chamber to be easily changed and cleaned without disturbing
the set-up of the viscometer or temperature bath. This means
that successive measurements can be made under identical
conditions.
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Temperature
Control : The sample chamber fits into a flow jacket so
that precise temperature control can be achieved when a
Brookfield circulating temperature bath is used. The stirring
action of the rotating spindle, plus the small sample volume
helps to keep the temperature gradient across the sample to a
minimum. Direct readout of sample temperature is provided
using sample chambers with embedded RTD sensors connected to
the DV-I+ (w/temperature option), Programmable DV-II+, or the
DV-III+. Working temperature range for the SSA is from -15oC
to 100oC.
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Cylindrical
Geometry : The Small Sample Adapter's rheoligically
correct cylindrical geometry provides extremely accurate
viscosity measurements and shear rate determinations.
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T he Ultra Low Adapter™
(ULA) accessory is used with Brookfield Viscometers/Rheometers to
make accurate and reproducible measurements on low viscosity
materials. The adapter is usable with all standard Viscometers/Rheometers
(excluding Cone/Plate models). It is commonly used with the LV
series instrument (at 60 rpm, these models have full scale range
of 1 - 10 cP with the ULA).
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Cylindrical
Geometry : The ULA consists of a precision cylindrical spindle
rotating inside an accurately machined tube. Its rheologically
correct cylindrical geometry provides extremely accurate
viscosity measurements and shear rate determinations. Also
available is the ULA-DIN spindle which conforms to DIN 53019
specifications.
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Measures Either
Small or Large Samples : The tube has a removable end cap.
With the cap removed, the open ended tube can be used in a
beaker or tank. With the cap in place, the closed tube holding
a 16 ml sample (17 ml with the DIN spindle) can be immersed in
a temperature bath or used with the ULA-40Y water jacket for
precise temperature control. Working temperature range for the
SSA is from -15oC to 100oC.
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Easily Cleaned :
All immersed parts are stainless steel. The removable cap of
low density polyethylene can be considered disposable for one-time
use if required.
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DIN Adapter
Accessory : Additional DIN spindles (conforming to DIN 53019)
are available. Optional DIN spindles are available
DIN Adapter Accessory
The DIN Adapter Accessory (DAA) is a cylindrical spindle geometry
that conforms to the DIN 53019 specification. Three spindles and
three chambers are provided. The DAA can be attached to any
standard Brookfield Laboratory Viscometer/Rheometer.
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For use with paste-like
materials, gels, and fluids where suspended solids migrate away
from the measurement surface of standard spindles.
Features And Benefits
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Minimal disurption
of sample during spindle immersion
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Keeps particles in
suspension during testing cycle
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Viscosity data
includes complete flow curve analysis
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Provides
information on yield behavior at low rotational speeds
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Follows industry
recommendations on length/diameter ratios for vane spindles
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3-piece spindle
set for versatile range capability
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Ideal for use with
the Programmable DV-II+ Viscometer and the DV-III+ Rheometer
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The Brookfield Helipath™ Stand, when used with a suitable
Brookfield Viscometer/Rheometer fitted with a special T-bar type
spindle, will permit viscosity/consistency measurements in relative
centipoise values for materials having characteristics similar to
paste, putty, cream, gelatin, or wax.
Many substances, because of the nature of their yield values, have
previously been considered unsuited for viscosity or consistency
measurements with rotational viscometers. Any rotating member, be it
cylinder, disc, or paddle, will create a channel in such substances
and after a very short time exert a negligible and meaningless
torque on any sensing device. This effect also occurs with materials
that have a gel structure.
Paint dyes, lithographic inks, and many other substances are
thixotropic in that their structure is broken down and their
viscosity is decreased when subjected to internal shearing. While no
rotating member will ever spin freely in such materials, the torque
required to produce this motion will become less as the period of
internal shearing lengthens. The study of such data will lead to
difficulties and necessarily rigid testing procedures in product
control work.
Other materials, notably pastes and creams, show a combination of
the two effects listed above. They will show a yield value as well
as a change in relative viscosity/consistency with time.
The Brookfield Helipath™ Stand is designed to slowly lower or
raise a Brookfield Viscometer/Rheometer so that its rotating
shearing element will describe a helical path through the test
sample. By always cutting into fresh material, the problem of
channeling or separating is eliminated and meaningful viscosity/consistency
measurements can be made. The reversing feature of the Helipath™
Stand allows measurements to be made over a variable period of time.
Spiral Adapter
A Pump-type Sensor That Directly Measures Viscosity Of Pastes :
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Applications include
foods, solder paste, cosmetics, pharmaceuticals, and other paste-like
materials
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Performs
measurements compatible with industry specifications
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Provides viscosity
data that show pseudoplastic and thixotropic properties of test
samples
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Delivers repeatable
measurements within ± 2%
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Works with any
standard Brookfield Viscometer/Rheometer
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Simple and fast to
operate; easy to clean
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Optional software
computes shear sensitivity factor
The Spiral Adapter has
an inner, threaded spindle surrounded by a concentric outer cylinder.
This combination causes the sample to be continually pumped up
through the Spiral Adapter. The material reaches a steady state of
flow during which viscosity is measured. The steady-state
measurement is less sensitive to sample handling and minor material
variations than other viscosity measuring methods.
At its various rotating speeds, the Brookfield Viscometer/Rheometer
provides viscosity data at different shear rates. The resulting
rheogram from an up/down speed ramp supplies important information
on the psuedoplastic and thixotropic behavior of the test material.
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The Quick Connect
spindle coupling accessory is designed to quickly attach or remove a
spindle from a Brookfield Viscometer/Rheometer.
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Quick connection -
saves time
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Easy to use
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Reduces viscometer
wear
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Eliminates cross
threading
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Stainless steel
construction
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Compatible with LV,
RV, HA, & HB disk spindles
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Compatible with
T-bar couplings (chuck, weight, and closer assembly)
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Convenient Quick
Connect "Kits" for LV (4 spindles) and RV/HA/HB (7
spindles); kits include a special guardleg where appropriate
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Type
S Extensions - Used for applications where depth of spindle
immersion cannot be observed.
Type
D Extensions -
Used for applications where the depth of spindle
immersion can be observed; can also be used without a link for rapid
spindle change.
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The Brookfield spindle
rack provides convenient, benchtop storage for Brookfield LV, RV,
HA, or HB Viscometer/Rheometer spindle sets. The attractive design
includes a long lasting epoxy finish which can be easily cleaned.
The rack will accomodate up to seven spindles.
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Viscosity Determination At Elevated Temperatures
How It Solves A Difficult Problem
The difficulty with viscosity measurements of hot melts and liquids
at elevated temperatures has been in maintaining accurate
temperature control that is consistent from sample to sample, so
that meaningful data could be obtained.
The Brookfield Thermosel® solves this problem by providing a stable,
precisely controlled sample environment. This, together with the
inherent accuracy of the Brookfield Viscometer, is fundamental to
the Thermosel® System, which produces viscosity measurements that
are not only accurate, but entirely reproducible. Several factors
contribute to the stable environment:
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Non-fluctuating
temperature control
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Small sample volume
and insulated sample chamber, which reduces temperature
gradients with the sample
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The rotating spindle,
which acts as a built-in stirring device
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Expedited research
and QC procedures
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Safe viscosity
measurements of materials up to 300oC
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Precise temperature
control within ±0.5% of set point temperature
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Excellent viscosity
reproducibility
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Small sample volume
(8 to 13 ml)
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Defined shear rates
generated by coaxial cylinder geometry
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Manual or
programmable temperature control
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Digital display of
set point and Thermosel® temperature to 0.1oC or oF on
controller
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Temperature display
switchable to oC or oF
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Disposable sample
chambers
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DIN spindle geometry
available
Various spindles are
available for use with the Thermosel® System. Selection is
determined by the viscosity measurement range that is required.
Included with the Thermosel® are a thermo-container, safety guard
and insulating cap, a proportional controller with RTD probe, one
spindle (others available), one standard sample chamber, five
disposable chambers, sample chamber holder, extraction tools, and an
alignment bracket.
The Model 106 Programmable Temperature Controller allows up to 10
pre-programmed test steps which include both a set temperature and
hold time at that temperature. This permits measurement of viscosity-temperature
data for any test sample. The Model 75 Temperature Controller (single
set point) is also available.
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Why control
temperature for viscosity measurement?
Detecting changes in your sample's properties is valuable
information for predicting your product's performance. Temperature
control during viscosity measurement helps insure accurate test
results. The addition of a Brookfield Circulating Bath is a smart
investment.
Digital Controllers have easy-to-use controls. Just dial in
your set-point and push a button, you're done!
Programmable
Controllers offer the highest level of flexibility and control
for the most demanding applications.
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Easy-to-read LCD
alphanumeric display
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Intuitive, easy-to-use
keypad
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Time and temperature
programming
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Built-in RS-232
interface for use with appropriate application software
providing automated temperature control
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Brookfield Viscosity
Standard Fluids provide a convenient, reliable way to verify the
calibration of your Brookfield Laboratory Viscometers/Rheometers.
Brookfield Viscosity Standards are Newtonian, and they are
available as either silicone or oil.
Silicone Viscosity Standards
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Accuracy ±1%
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Excellent
temperature stability
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Special viscosity
values and temperatures available upon request
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Recommended for
use with Brookfield and most other rotational viscometers
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Most economical
Oil Viscosity
Standards
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Accuracy ±1%
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Appropriate for
use at shear rates greater than 500 sec-1
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Recommended for
use with Cone/Plate viscometers at viscosities above 5000 cP
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Recommended for
Brookfield CAP series and KU-1+ viscometers
Brookfield Viscosity
Standard Fluids are accurate to ±1% of the stated viscosity and
are certified by methods traceable to the United States National
Institute of Standards and Technology (NIST). The selection of one
or two fluids will normally provide sufficient measurement points
to verify calibration of your instrument. All fluids are supplied
in ½ liter (1 pint) containers and with a certificate of
calibration.
Special Order Silicone Fluids
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Viscosity Blends
at 25oC (77oF) Fluids may be ordered
with viscosities other than those listed for general purpose
silicone fluids.
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Minimum: 5 cP (mPaos)
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Maximum: 60,000 cP
(mPa·s)
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Blends will be
within ±2% of requested value
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Temperature
Calibrations
General purpose or
blended fluids may be calibrated at temperatures other than 25oC
(77oF).
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