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BENDING BEAM RHEOMETER BBR

BENDING BEAM RHEOMETER BBR

SHRP Standard Test Method B-002

DEFINITION

BENDING BEAM RHEOMETER

Safest, easiest, most accurate, and most versatile BBR commercially available.

Eliminates cooling pump. Cools below -40 C using ethyline glycol mixture.

The Bending Beam Rheometer is a complete test system engineered specifically to perform flexural tests on asphalt binder and similar specimens in accordance with SHRP Standard Test Method B-002. The system was designed according to specifications developed by the Strategic Highway Research Program (SHRP) to measure flexural creep stiffness properties of asphalt binders at various temperatures.

COOLING METHOD - NO PUMPING REQUIRED

  • Uses Ethylene Glycol Mixture to -40 C.
  • Requires only half as much fluid as other BBR's.
  • Drain installed for easy fluid replacement
  • No 'guessing' the temperature setting. If the test requires -38.0, set the temperature for -38.0. No 'fudge factor' is involved.

  • COMPUTER CONTROL, ACQUISITION AND ANALYSIS

    The software is an user friendly package that walks the operator through device configuration, daily verification, test setup, test initiation, and reporting.

    The software allows changes to many of the test set-up, run, and analysis sequences, so future changes to SHRP specifications, as well as other non tests may be performed. Changes are permitted in all specimen dimensions; test pre-load, recovery, and test load times; data acquisition points; and the temperature recording point.

    The data acquisition system saves all raw data points, test specimen/set-up data, and the test report, in standard ASCII data files that can be recalled, printed, or imported into other software packages for further analysis or custom reporting.

    Constant system error checking assures that the correct parameters have been set prior to test initiation, so specimens are not accidentally destroyed before running a valid test.

    FEATURES

  • Meets SHRP -B-002 specification for determining the flexural creep stiffness of asphalt binders.
  • Computer-controlled loading, data acquisition and analysis.
  • PID Controller with digital display of temperature.
  • Mechanical refrigerated cooling bath provides test temperatures of -40 to 25 C.
  • Heat exchanger in test bath eliminates coolant pump and allows use of Glycol mix at temperatures to -40C.
  • Corrosion resistant construction for long reliable service.
  • Shipping Weight: 250 Ibs. (115 kg)


  • CONSTRUCTION

    The Bending Beam Rheometer is constructed of stainless steel and durable high strength polymer components.

    An air bearing assures reliable loading with accurate and repeatable results.

    The load frame incorporates an integral Linear Variable Displacement Transducer (LVDT) and a temperature compensated load cell to ensure accurate test results.

    Internal mechanical load cell overload protection is standard.

    COOLING BATH

    Our new and unique style of cooling provides safe and easy cooling of the test fluid to -40 C. This is the only BBR cooling method commercially available for which the recommended Ethylene Glycol/Water/Methanol mixture can be used forthe full range of testing temperatures, providing a safer way to perform the tests.

    The test temperature is controlled and monitored by two independent platinum RTD temperature transducers to maintain test bath temperature stability. The mechanical refrigeration system uses environmentally safe (non-CFC) refrigerant to provide long term maintainability.

    DEVICE CALIBRATION/ VERIFICATION

    The Bending Beam Rheometer incorporates software programs for daily verification and periodic calibration of the load cell, LVDT, and R.T.D. transducers. Calibrated test weights and a certified LVDT calibration standard, traceable to the National Institute of Standards and Testing (NIST), are provided with each system.

    Daily verification of the load cell and LVDTtransducers are easily accomplished in a few minutes.

    Bath temperature can be verified at any time using an ASTM certified thermometer.

    The Bending Beam Rheometer also incorporates a program to verity and eliminate device compliance from the specimen displacement measurements. To verify total system accuracy, a certified confidence test beam is provided with each Rheometer. This stainless steel standard can be used for daily confirmation of the software, electronics, pneumatics, and analysis systems. Deviation from the standard values for this beam indicate the need for calibration or maintenance.

    SYSTEM CONFIGURATION

    SAMPLE SUPPORTS
    - 25mm diameter stainless steel spaced 101.6 mm apart

    LOADING SHAFT
    In-line stainless steel with blunt loading point.

    LOAD CELL
    250 gram standard to permit highest resolution at the required loading range (100 gram). Temperature compensated
    Internal mechanical overload protection.

    LVDT
    6.35 mm calibrated range to provide 2uM resolution throughout test and verification range.

    TEST LOAD
    Variable test range from 0 to 200 grams standard. System maintains required test load within 0.5 gram throughout test cycle.

    TEST CYCLE TIMES Cycle times for pre-load, recovery, and test load are completely operator adjustable.

    ANALYSIS DATA Data acquisition points are operator selectable. Default values comply with current SHRP - B-002 specifications.

    DATA DISPLAY
    Large on-screen display of load, displacement, and bath temperature provides ease of set-up and operation. Real time displacement, loading, and temperature graphs are displayed during the test cycle and can be re-plotted and re-scaled at any time.

    SYSTEM REQUIREMENTS:

    ELECTRICAL
    115 V, 50/60 Hz, (220 V, 50 Hz - optional)

    COMPRESSED AIR
    50 PSIG minimum, clean, dry air ( is not included)