Beam Bending Viscosity
The Model BBV series instrument is a versatile beam bending viscometer system that can determine;
- annealing & strain point temperatures of a solid glass beam according to the ASTM C-598 procedure or,
- the temperatures for a range of viscosities of a solid glass beam according to the ASTM C-1350m procedure.
The annealing and strain points of a glass are widely used production control parameters. Changes in the annealing and strain point temperatures are indications of chemistry changes. If forming a fiber is not desired, is impractical, or impossible, annealing and strain point temperatures can still be determined using cut or machined rods or bars in a beam bending viscometer according to ASTM C-598.
The annealing point temperature is the temperature at which a 2-point supported horizontal bar or rod with a uniform cross section deflects under an applied mid-point load at a prescribed calculated rate while cooling in a special furnace at the rate of 4°C per minute. The strain point temperature is determined by extrapolation of the annealing point data and is the temperature at which the mid point deflection rate is 0.0316 times the deflection rate observed at the annealing point.
These tests are performed with an LVDT extensometer system that is manufactured by Orton. The Model BBV Series has been designed to automatically monitor the deflection of the sample beam and calculate the annealing and strain points according to the ASTM C-598 method, or calculate the temperature for a range of viscosities according to the ASTM C-1350M method.
Model BBV-1200
General
A laboratory bench-top system for automatically determining annealing point temperature, strain point temperature or viscosity (Log poise 14.0 – 9.0) of a solid glass beam, rod, or tube below 1200C.
Operated according to ASTM C598, ASTM C1350M or modified versions of those test procedures.
Includes
- Bench top instrument console
- 1200°C furnace
- programmable process controller
- measuring head with alumina sample pedestal (50mm diameter) and alumina load rod
- type “S thermocouple
- load weights
- computer software
- accessories and instruction manual. (Computer not included.)
Specifications
| Model | BBV-1200 |
| Warranty | 12 Months |
| Range | Log 14.0 – Log 9.0 Poises |
| Atmosphere | Air |
| Temperature Range | RT to 1,200°C |
| Furnace | Tube style |
| LVDT Displacement Range | ±0.500 inch (±12.7 mm) |
| LVDT Sensitivity | 0.7 mV/V/.001 inch(28 mV/V/mm) |
| Mass Set | Slotted weight set 1-500 Grams |
| Thermocouple | Type “S |
| Sample Size | 2.53 to 3.78mm dia. Rod (or) 2.21 to 3.31mm bar |
| Power Requirements | 120vac/10amp or 240vac/5amp 50 or 60 Hz |
| Computer Requirements | Desktop with available PCI slot |
| Power Control | SSR |
| Pedestal | Alumina – 50mm diameter |
| Load rod | Alumina Shepherds hook |
| Furnace Movement | Manual lift |
| Temperature Control | Honeywell UDC 3200 Process controller |
| Computer Interface Software | Included |
| Bench-top Footprint (stand)Length x Depth x Height | 12 x 14 x 33 (31 x 36 x 84 cm) |
| Bench-top Footprint (controller)Length x Depth x Height | 18 x 12 x 5 (46 x 31 x 13 cm) |