Gravimetric Capillary Viscometer / Ubbelohde manual
Using gravity as the driving force, capillary viscometers are reliable and precise. They are widespread and have numerous standards referring to them. To obtain exact readings with the original glass capillary viscometers requires a high level of concentration from the operator when taking the flow time manually. Thermostat baths and suitable bath liquids that stay clear when measuring at low temperatures are essential in order to obtain correct results. Precise temperature equilibration takes typically several hours. The listed specifications apply to manual Ubbelohde capillaries.
Physics
- Measured quantity: Time
- Calculated quantity: Kinematic viscosity
Learn more about the Gravimetric Capillary Principle.
Performance
Many different capillaries (also referred to as 'tubes') are required to cover a wide viscosity range. Each Ubbelohde capillary can cover a range defined by its minimum viscosity times factor 5. For example, the range for type 0B is 1 mm2/s to 5 mm2/s.
- Viscosity measuring range - 16 capillaries for the entire range: 0.3 mm2/s to 100,000 mm2
- Repeatability: < 1 %
- Reproducibility: 0.65 %
- Temperature measuring range: -40°C (-40°F) to +200°C (392°F)
Sample throughput - max./hour for manual operation:
- typically 2, depending on sample type and measuring conditions
Temperature control
A liquid bath is required for temperature control. The capillary is immersed in the bath.
Sample
The sample volume depends on the capillary used.
Typical sample volume for an Ubbelohde capillary: 18 mL
- Suitable for transparent samples.
- Other, reverse-flow glass capillary types are suitable also for opaque samples (e.g. Cannon-Fenske Opaque).
Standards and Norms
ISO 3104, ISO 3105, ASTM D445, ASTM D446, IP 71, BS 188, USP <911>
Overview
Viscometer type | Gravimetric Capillary Viscometer / manual |
---|---|
Measuring principle | Gravimetric Capillary Viscometer |
manual | |
Ubbelohde | |
Measured quantity | time |
Calculated quantity | kinematic viscosity |
Viscosity range - min | 0.3 mm²/s |
Viscosity range - max | 100,000 mm²/s |
Temperature - min | -40°C |
Temperature - max | +200°C |
Liquid bath thermostat required | yes |
Temperature change with same filling | no |
Automation possible | no |
Sample volume - typical | 18 mL |
Solvent volume - typical | 30 mL |
Sample throughput - max / h | 2 |
Measuring accuracy | < 1 % |
Shear rate control | no |
Shear rate calculation | no |
Lab space | approx. 0.5 m² |
Standards and norms | ISO 3104, ISO 3105, ASTM D 445, ASTM D 446, IP 71, BS 188, USP <911> |
We offer typical values which are based on the values in brochures and standards but are not related to specific instruments.