AccuPyc II

Gas Displacement Pycnometry System

Best-in-class density measurements
High thermal mass design improves measurement stability
Self-aligning enclosure simplifies operation and guarantees precision

Quote Accessories

The AccuPyc II Series of Pycnometers (Gas pycnometer) provides high-speed, high-precision measurements for determining the true density of powders, solids, and slurries. The analyst enters the mass of the material and then with a few keystrokes the measurement is initiated, several measurements are performed, and the density of the material is displayed.

Gas pycnometry is recognized as one of the most reliable techniques for obtaining true, absolute, skeletal, and apparent volume and density. This non-destructive technique utilizes the gas displacement method to measure the volume of a material. Inert gases, such as helium or nitrogen, are commonly used as the displacement medium for gas pycnometry. Density determinations from the gas displacement method are more accurate, reproducible, and faster than the traditional Archimedes water displacement method.

Features and Benefits:

Maintain product integrity with this non-destructive test	Eliminate error with programmable automatic repeat and data acquisition set to your tolerances to comply with your SOPs	Ability to use a variety of gases
Maximize your investment-Adaptive configuration to meet your sample size needs	Low-cost, minimal maintenance, and small footprint	Increase efficiency and compliance with barcoding compatibility
Speed of analysis, accuracy, repeatability, and reproducibility	Versatility of keypad or Windows software operation	Eliminate procedural steps with direct input from an analytical balance

Specifications

Operating Environment

Temperature	Stable between 15 to 35 °C (59 to 96 °F) Temperature-controlled AccuPyc: temperature stability is dependent upon specifications of the installed circulator. Recommended range: 15 to 50 °C (59 to 122 °F)
Humidity	20 to 80% relative, non-condensing

Physical

Height	14.6 cm (5.8 in.) 17.9 cm (7.0 in.), analysis modules for 1-, 10-, and 100-cm³ units
Width	27.3 cm (10.7 in.), control module (no chamber) 27.3 cm (10.7 in.), control module (with chamber)
Depth	36.2 cm (14.3 in.)
Weight	9.3 kg (20.5 lbs), control/analysis unit (1-, 10-, and 100-cm³ units) 7.9 kg (17.4 lbs), analysis module (1-, 10-, and 100 cm³ units)

Electrical

Voltage	90 to 264 VAC
Power	30 VA
Frequency	50 to 60 Hz

Gases

Research grade helium is recommended. If unavailable, use helium with a dew point of -67 °C (-88 °F) or lower. Carbon dioxide, argon, dry air, or nitrogen can also be used for different applications (a multigas option is available for connection of mulitple gases).

Sample Cups

1 cm³ chamber	1.14 cm ID x 1.1 cm D (0.45 in. ID x 0.44 in. D)
10 cm³ chamber	1.85 cm ID x 3.95 cm D (0.72 in. ID x 1.55 in. D)
100 cm³ chamber	4.62 cm ID x 6.18 cm D (1.82 in. ID x 2.43 in. D)

Analysis

Precision	Reproducibility is typically to within ± 0.01% of the nominal full-scale sample chamber volume. Reproducibility is guaranteed to within ±0.02% of the nominal full-scale volume on clean, dry, thermally equilibrated samples using helium in the 15 to 35 °C range.
Accuracy	Accurate to within 0.03% of reading, plus 0.03% of sample capacity

* Should not be installed on a network drive with shared access. Multiple users cannot operate the application at the same time. All users need read/write permission to all directories and subdirectories where the application is installed.

* Due to continuous improvements, specifications are subject to change without notice

Gas Displacement Pycnometry

Principle of Operation

PRINCIPLE OF OPERATION

This technique uses the gas displacement method to measure volume accurately. Inert gases, such as helium or nitrogen, are used as the displacement medium. The sample is sealed in the instrument compartment of known volume, the appropriate inert gas is admitted, and then expanded into another precision internal volume. The pressures observed upon filling the sample chamber and then discharging it into a second empty chamber allow computation of the sample solid phase volume. Helium molecules rapidly fill pores as small as one angstrom
in diameter; only the solid phase of the sample displaces the gas. Dividing this volume into the sample weight gives the gas displacement density.

Inert gas flows Into sample chamber – valve a opens then closes
Equilibrium is reached
Gas flows into second chamber for volume measurement – valve b opens
Equilibrium is reached yet again
Volume divided into sample weight determines density
Pressure vented off to atmosphere – valve c opens

Density Measurement

DENSITY MEASUREMENT

On an elementary level, the volume of a solid material can be calculated by measuring its length, width, and thickness. However, many materials have within their structure surface irregularities, small fractures, fissures, and pores. Some of these voids or pores are open to the surface or closed within the structure of the solid material. Therefore, differences in the material volume depend on the measurement technique, measurement method, and the conditions under which the measurements were performed.

Density Type	Definition	Material Volume	Open-Pore Volume	Closed-Pore Volume	Inter particle Volume	External Void Volume	Addressed by
True (Absolute	The mass of a substance divided by its volume, excluding open and closed (or blind) pores	✓					AccuPyc II
Skeletal (Apparent)	The ratio of the mass of the solid material to the sum of the volume including closed (or blind) pores	✓		✓			AccuPyc II
Envelope	The ratio of the mass of a substance to the envelope volume (imaginary boundary surrounding the particle)	✓	✓	✓		✓	GeoPyc
Bulk	Mass of the material divided by the volume occupied that includes interstitial space	✓	✓	✓	✓		GeoPyc
Tap	Apparent powder density obtained under stated conditions of tapping	✓	✓	✓	✓		GeoPyc with T.A.P. function

Highly Adaptive System

HIGHLY ADAPTIVE SYSTEM
The AccuPyc II Pycnometer consists of an integrated control and analysis module. For those who require high throughput, analysis modules are also available in a single configuration, allowing you to attach up to five additional analysis modules to a single controlling unit. Each module has its own gas connection. A variety of sample chamber sizes can be selected to provide the best fit with your samples. The run precision mode allows you to achieve high repeatability. The instrument purges water and volatiles from the sample and then repeats the analysis until successive measurements converge upon a consistent result.

UNIQUE RUN PRECISION

Increases the precision of analysis results by reporting data from five consecutive measurements that are within a user-specified tolerance. This feature allows early termination of analysis, thereby decreasing the number of cycles needed for accurate results.

INTEGRATED CONTROL AND ANALYSIS MODULE

Can control up to five additional external analysis modules

MULTILINGUAL

The AccuPyc may be operated in five languages: English, French, German, Italian, or Spanish

ETHERNET PORT

An Ethernet port on the rear panel of the control module enables you to email reports, send data to a web browser for archiving, or interface with the AccuPyc Windows application

USB PORTS

USB ports on the rear panel of the control module allow for connection to a printer (output of analysis and calibration results in either ASCII or Excel formats) and keyboard (alphanumeric character input). The USB port is also used for installing software upgrades.

SIMPLE CALIBRATION PROCESS

Allows you to easily determine the volume of the instrument sample cell and expansion chambers using a traceable standard volume. After calibration, the cell and expansion chamber volumes are stored automatically

DIRECT SAMPLE MASS INPUT

Sample mass may be directly input from an analytical balance

BAYONET CAP FITTING

Provides superior repeatable seal compared to screw-type fitting

FIVE STANDARD SAMPLE CHAMBER SIZES

1 cm3 , 10 cm3 and 100 cm3

Hardware Versatility

HARDWARE VERSATILITY

MULTIVOLUME KITS

A MultiVolume option allowing you to analyze smaller-sized samples with your current AccuPyc model is available for configurations listed below. Each kit includes appropriate insert(s), reference standard(s), and sample cup(s).

Application

Application	Discussion	Reference
Powder Metallurgy	Results of many intermediate and final processing steps are controlled by or related to skeletal density of the metal. In addition, the performance of many sintered or cast metal structures may be predicted from the skeletal density of the starting metal powder	ASTM B923
Refractory Materials	True density is a useful value for: classification, detecting differences in chemical composition between supposedly similar samples, indicating mineralogical phases or phase changes, calculating total porosity when the bulk density is known, and for any other test method that requires this value for the calculation of results	ASTM C604
Calcined Petroleum Coke	The density of calcined petroleum coke directly influences the physical and chemical properties of the manufactured carbon and graphite artifacts for which it is used. Density, therefore, is a major quality specification of calcined petroleum coke and is used as a control in coke calcination	ASTM D2638
Soil	The specific gravity of soils that contain extraneous matter (such as cement, lime, etc.) or water-soluble material (such as salt) must be corrected because of the precipitate that forms on the specimen after drying. If the precipitate has a specific gravity less than the parent soil grains, the uncorrected test result will be too low. If the precipitate has a higher specific gravity, then the uncorrected test value will be too high.	ASTM D5550
Powder Coatings	Total solids content can be used to determine minimum coverage obtainable with different coating blends. Mixtures of dry pigments can be monitored by comparing measured density with theoretical density based upon composition of the mixture.	ASTM D5965
Clear or Pigmented Coatings	Dried film density can be used in the determination of Volatile Organic Compound (VOC) content of clear and pigmented coatings. VOC is required by government regulations.	ASTM D6093
Rigid Cellular Plastics	Plastic foams exhibit different properties based upon the ratio of open and closed cells. Insulation foams limit thermal conductivity through pockets of trapped gases contained within closed cells. Flotation devices owe buoyancy to closed air-filled cells that prohibit water entry.	ASTM D6226
Pharmaceuticals	Composition of active and excipient ingredients can be monitored and controlled through determination of product density. Polymorphic, hydrated, and amorphous forms of products, as well as purity, can be determined by comparing measured density with theoretical and historical values.	USP 699

FERTILIZERS

Knowledge of the bulk density is of interest in package sizing, in calibrating volumetric feeders or applicators, and in determining the storage capacity of bins and transport vehicles. Apparent density information can be used in segregation studies and development of granulation processes. True density measurements are important in
process control and the design of process equipment

MINING CORES

Simple physical measurements of a circular core cylinder’s diameter and length allow the envelope volume to be calculated. A gas displacement pycnometer, with a larger sample chamber designed specifically to accept intact drill cores, provides a low-cost, time-saving, non-destructive technique for measuring the skeletal volume. Knowing the envelope and skeletal volumes allows the total pore volume and percent porosity of the core sample to be determined.

COSMETICS

The presence of air bubbles in cosmetic preparations, such as lipsticks and powder cakes, is undesirable for a
number of reasons. Trapped air can create pinholes and poor appearance in lipsticks and compromise the integrity of cakes. The effectiveness of different methods of air bubble removal can be evaluated by comparing the true density measurements of the material before and after air bubble removal

Configuration/Model Selection

AccuPyc II 1345 Instruments

Sample Cup Capacity	Sample Cup Dimensions	Available MultiVolume Insert Kits	Temp Control Type	Catalog Number
1 cm³	1.14 cm ID x 1.1 cm D	0.1 cm³	N/A	134/50001/00
10 cm³	1.85 cm ID x 3.95 cm D	1.0 and 3.5 cm³	N/A	134/50000/00
100 cm³	4.62 cm ID x 6.18 cm D	10 and 35 cm³	N/A	134/50002/00

AccuPyc II 1345 Remote Analysis Instruments

Remote analysis modules only. Remote analysis units require connection to a control module or AccuPyc II 1345.

Sample Cup Capacity	Sample Cup Dimensions	Available MultiVolume Insert Kits	Temp Control Type	Catalog Number
10 cm³	1.85 cm ID x 3.95 cm D	1.0 and 3.5 cm³	N/A	134/50040/00

AccuPyc II 1345 Temperature-Controlled Instruments

Sample Cup Capacity	Sample Cup Dimensions	Available MultiVolume Insert Kits	Temp Control Type	Catalog Number
10 cm³	1.85 cm ID x 3.95 cm D	1.0 and 3.5 cm³	Use with External Recirculating Bath 15-50 °C	134/50010/00
100 cm³	4.62 cm ID x 6.18 cm D	10 and 35 cm³	Use with External Recirculating Bath 15-50 °C	134/50020/00
10 cm³	1.85 cm ID x 3.95 cm D	1.0 and 3.5 cm³	Integral Thermoelectric Cooling 15-36 °C ±0.1 °C	134/50050/00
100 cm³	4.62 cm ID x 6.18 cm D	10 and 35 cm³	Integral Thermoelectric Cooling 15-36 °C ±0.1 °C	134/50051/00

Accessories

Quote Accessories

Foam Solution

FOAMPYC – DENSITY MEASUREMENTS FOR OPEN- AND CLOSED-CELL FOAMS

The AccuPyc II unit can be ordered initially with the FoamPyc application installed. If you have a standard AccuPyc, you can upgrade with a software enhancement. A FoamPyc option for measuring open- and closed-cell foam materials is available in the following configurations for the standard and temperature-controlled pycnometers:

10-cm3 nominal cell volume
100-cm3 nominal cell volume (for conformance to ASTM and ISO methods

Weighing Solution

ANALYTICAL BALANCE

The AccuPyc weighing solution provides one-touch transfer of mass data from the analytical balance directly to the AccuPyc’s Windows software. Direct transfer eliminates user error associated with manual entry of mass data.

Seamless device compatibility
One-touch mass data transfer to AccuPyc for automatic calculation of density
Includes 120 X 0.01 mg electronic analytical balance with calibration weight

Temperature Control Solution

ACCUPYC II TEC – DENSITY TESTING FOR SEMI-SOLID MATERIALS

This AccuPyc solution can be closely correlated (< 0.15% difference) to results obtained with ASTM Test Method D70-09. The ASTM method is burdensome and time consuming. Our approach offers an expedited, more robust, operator-independent method, with results in minutes.

Reproducible results in minutes, virtually eliminates operator error
Integral solution with software for bituminous material testing includes results for specific gravity, volume, and density. As well as reported density corrected to 60 °F.
Peltier thermoelectric control (15 to 36 °C) provides excellent temperature control/stability and sample handling
Optional 3.3 cm3 disposable sample cups limit crosscontamination and minimize cleaning of sample chamber between analyses

Consumables & Supplies

Consumables & Supplies

Software Versitility

Downoad Software

Data Representation

The AccuPyc II can be operated with a full keyboard or an optional Windows® interface that provides exceptional reporting and archiving capability. Both versions include direct sample mass input from a balance and cycle-based displacement volume reporting. With the Windows interface, features such as time-based pressure equilibration reporting and additional calculations such as percent solids content and total pore volume are included. Operational status can also be continually monitored in a status window on the monitor screen.