Bending Beam Rheometer BBR
AASHTO R28 ASTM D6521
The Bending Beam Rheometer (BBR) has been engineered to perform flexural tests on asphalt binder and similar specimens per ASTM D6648-01 and AASHTO T313-02. These tests, initially developed by the Strategic Highway Research Program (SHRP), consist of a constant force being applied to a specimen in a chilled fluid bath in order to derive specific rates of deformation at various temperatures.
A complete BBR system consists of a fluid bath base unit, a three-point bend test apparatus which is easily removed from the base unit for specimen loading and unloading, an external cooling unit with temperature controller, and a calibration hardware kit with carrying case. Additionally, the BBR has recently been redesigned according to the latest revisions of the relevant ASTM and AASHTO specifications. This new design includes updated and improved software as well as features that make the BBR safer, easier, and more accurate.
- Durable Corrosion Resistant Construction
- Computerized control, data acquisition & analysis
- PID Temperature Controller with Digital Display
- Two independent platinum RTDs for precise Temperature Control
- Mechanically Refrigerated cooling bath with environmentally safe non-CFC coolant
- Integral LVTD & temperature-compensated load cell for accurate test results
- Patented air bearing ensures reliable loading with accurate repeatable results
- Includes complete calibration kit with carry case
- Includes ASTM/AASHTO-compliant specimen molds
- Load Frame Integral stainless steel frictionless construction
- Loading Shaft In-line stainless steel with blunt point
- Test Load Variable test range from 0 to 200g standard
- System maintains required test load within
±0.5g throughout the test cycle
- Test Cycle Times Cycle times for pre-load, recovery, and test
load are completely operator-adjustable
- Load Cell 500g (temperature-compensated)
- Mechanical Overload Protection Standard
- Test Weights Calibrated and traceable to NIST
- Sample Supports 25mm (0.98 in.) diameter stainless steel
spaced 4.00 in. (101.6mm) apart
- LVDT Displacement Transducer 0.25 in. (6.35mm) calibrated range to provide 2um
resolution throughout testing and verification range
- Data Display Large on-screen display of load, displacement, and bath
temperature provides ease of setup and operation.
- Real-time displacement, loading, and temperature
graphs are displayed during the test cycle and can
be re-plotted and re-scaled as needed for easy viewing
- Cooling Unit Included (non-CFC refrigerant)
- Recommended Cooling Bath Fluid Non-flammable ethylene glycol mixture
- Operating Temperature Ambient to -40°F (-40°C)
- Temperature Measurement Platinum RTD
- Power Requirements 115VAC 50/60Hz Standard
230VAC 50Hz Optional
- Compressed Air Requirements 50 psi (0.34 MPa) clean, dry air supply required
- Approximate Shipping Weight 250 lbs. (115kg)
Introducing the New Step Disk and Calibration Gaging Kit
The latest and probably the most useful innovation in the Bending Beam Rheometer is the totally redesigned calibration step disk. The new disk design makes calibration of the BBR load frame easier and more reliable than ever before.
The original notched step disk had a tendency to slide and distort the consistency of readings. The new design features a detent locking mechanism to prevent movement of the disk during calibration and incorporates a series of precision ball bearings as calibration steps.
Now, there is no longer the chance of recording a myriad of readings and the subsequent need to recalibrate. The new disk stays in place during the process, and the use of ball bearings means that there can be only one point of contact with the indicator pin, offering an unmatched level of precision and quality assurance.
The new calibration gaging kit includes the redesigned step disk, four 50g weights, two 2g weights, one certified confidence beam, one non-compliance beam, improved calibration software, and an attractive wooden carrying
The new BBR includes a number of improved software and reporting features:
- Recording of data points is now twice as accurate (two readings per second as opposed to one).
- For verification that seating loads were within specifications, a graph shows the pre-load results before the initial tests and can be viewed digitally at a later time.
- The pre-test mode includes continuous contact between the loading shaft, anvils, and specimen, and the applying and reapplying of 35mN and 980mN of force.
- The intuitive software package walks the user through device configuration, daily verifications, test setup, test initiation, and reporting.
- All test parameters can be changed, so any future revisions to the ASTM/AASHTO standards can be accommodated.
- The data acquisition system records all raw data points, test specimen/setup data, and the test report in standard ASCII files that can be recalled, printed, or imported into other software packages for further analysis or custom reporting.
- Constant system error checking ensures that the correct parameters have been set prior to test initiation, so specimens are not accidentally destroyed before running the test.
- The new software improves the ease and repeatability of performing routine calibration and verification to comply with the latest ASTM/AASHTO specifications.
- Features increased analysis and reporting, including data on temperature and the quality of the constant force.
- Reports contain a "test conditions" section, which includes machine serial number, software version, and the latest calibration dates and results, allowing improved traceability.
- Indication of return to original load at the end of the test is now a standard part of the report.
- Daily verification and periodic calibration of the load cell, LVDT, and RTD transducers takes only a few minutes to complete.
- The BBR software now incorporates a program to verify and eliminate device compliance from the specimen displacement measurements.
- A BBR Upgrade Kit is also available for older ATS Bending Beam Rheometers, which includes all updated software as well as the new calibration gaging kit and step disk.
See Also - Pressure Aging Vessel PAV
See Also - Vacuum Degassing Oven VDO