Description
The new SediGraph™ III 5120 determines
particle size by using the highly accurate and reproducible sedimentation
technique which measures the gravity-induced settling rates of different size
particles in a liquid with known properties.
This is simple yet extremely effective technique for providing particle size
information for a wide variety of materials.
Features
- Measures particles ranging from 300 to 0.10 µm equivalent spherical
diameter
- Utilizes a modern pumping system that is silent, reliable, and easy to
maintain.
- A maintenance reminder, based on the number of analyses performed, alerts
you when it is time for routine maintenance
- Computer –controlled mixing chamber temperature improves repeatability
and reproducibility
- A highly versatile and interactive reporting system provides a wide range
of custom data presentation options including dynamic reformatting of plots
and cut-and-paste graphics and tables.
- Particle settling velocity is reported as graphical and tabular data.
- Grain size can be reported in Phi units
- Provides SPC reporting and regression analyses.
- Runs up to 18 samples unattended using the MasterTech 052 Autosampler ,
which sits securely on top of the SediGraph to conserve bench space.
- Completes most analyses in 15 minutes or less
Key features:
- Complete particle accountability
assures that all of the introduced
sample is accounted for, including fractions below 0.1 µm
- Capability to merge data
with that from other particle sizing
methods, thus extending the range of reported data to 125,000 µm (125 mm),
excellent for geological applications
- Scanning the sedimentation cell
from bottom to top allows accurate
inventory of fast-settling particles while minimizing the time required to
resolve the separation of fine particles
- Fully automatic operation
increases sample throughput and reduces
operator involvement in addition to reducing the opportunity for human error
- Temperature-controlled analyses
assure that liquid properties remain
constant throughout the analysis so you can be confident of accurate and
reproducible results
- Multiple analysis speeds
allow you to choose the desired combination
of speed and resolution that meets your needs
- Real-Time display
allows you to monitor the cumulative mass plot of
the current analysis and to make immediate procedural changes if needed
- Statistical process control (SPC) reports
track the performance of
your processes allowing immediate response to fluctuations
- Plot overlays
provide a visual comparison of analysis results from
one or more analyses; a reference or baseline analysis, for example, or a
superposition of two different types of plots of the same analysis data
- Data comparison plots
provide graphical displays of the mathematical
difference between two data sets (difference from reference plot) or the
extent of a data point value above or below a tolerance boundary (out of
specification plot)
- Multiple analyzer control
allows two SediGraph III’s to be
operated simultaneously from a single computer, conserving valuable lab
space and making data storage convenient
Data Reporting Detailed analysis data for particles ranging from 300
to 0.1 µm are provided automatically by the SediGraph III. Data collected
from other particle size analyses ranging from 125,000 to 300 µm can be
combined with SediGraph data, enabling effective reporting for particles
ranging from 125,000 to 0.1 µm. That fraction finer than 0.1 µm is also
indicated. In addition to tabular data, different graphical analysis plot
types are available including:
- Cumulative Mass, Area, and Number
- Distribution of Sample Quantity as a Function of Settling Velocity
- Process Control Charts
- Log Probability
- Baseline/Full Scale References
- Frequency Distribution
- Difference From Reference
- Out of Specification
- Rosin-Rammler Plots
- Regression Analyses
Plots can be overlaid for comparing the results from different samples or
for comparing different plot types from the same sample. This allows you to
compare analysis results to a standard. Plots can be rescaled to give you
the ability to scrutinize closely your graphical data.
A new column has been added to the tables and to the x-axis selection in the
graphs that reports size in Phi units, where Φ = -log2 (particle
diameter in mm). Also, a column selection for settling velocity (cm/s) is
available for tables. The x-axis of plots can be scaled in particle size or
settling velocity. The SediGraph is the only automated particle sizing
instrument that directly measures settling velocity.
Analysis Technique
Mass The SediGraph III uses a narrow,
horizontally collimated beam of X-rays to measure directly the relative mass
concentration of particles in the liquid medium. This is done by first measuring
the intensity of a reference X-ray beam which is projected through the clear
liquid medium prior to the introduction of the sample. A homogeneously dispersed
mixture of solid sample and liquid is next circulated through the cell. The
solid particles absorb some of the X-ray energy, which again is measured, this
time to establish a value for full scale attenuation. Agitation of the mixture
is ceased and the dispersion is allowed to settle while X-ray intensity is
monitored. During the sedimentation process, the largest particles are first to
fall below the measuring level, and each mass measurement represents the
cumulative mass fraction of the remaining fine particles. Gradually, finer and
finer particles settle out, ultimately clearing the measuring zone of suspended
particles and allowing the X-ray beam to again pass through the cell
unattenuated.
Size / Settling Velocity The SediGraph determines particle size
from velocity measurements by applying Stokes law under the known conditions of
liquid density and viscosity and particle density. Settling velocity is
determined at each relative mass measurement from knowledge of the distance the
X-ray beam is from the top of the sample cell and the time at which the mass
measurement was taken. From the velocity equals distance divided by time
relationship, it can be determined the maximum velocity of all particles
remaining above the measurement zone, these velocities being associated with the
finer particles. A sequence of closely-spaced measurements provides a
distribution of mass fraction remaining in suspension versus velocity or size
class or, as more commonly termed, cumulative mass percent finer.
Technical Specifications
A full set of technical spec will be published shortly.
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