Rolling-Ball Microviscometer
The rolling-ball microviscometer is based on the Hoeppler principle like the classic falling-ball viscometer. Instead of the original wide falling tube this instrument uses micro capillaries so that only extremely low sample volume is required. In addition, special capillaries are available for substances that corrode glass. Optional gold-coated balls enhance the system's resistance to aggressive chemicals further. The time is taken by inductive sensors. Thermoelectric temperature control and adjustable inclination angles extend the potential measuring range. Automated measurement is a further possibility.
Physics
- Measured quantity: Time
- Calculated quantity (sample density required): Dynamic/kinematic viscosity
Learn more about the Falling Ball Principle.
Performance
The measuring range of the rolling-ball microviscometer depends on the capillary/ball combination used.
- Viscosity measuring range - with 3 different capillaries: 0.3 mPa.s to 10,000 mPa.s
- Repeatability: up to 0.1 % (without changing the ball)
- Temperature measuring range: -30°C (-22°F) to 100°C (212°F)
Sample throughput - max./hour:
- Manual operation: 10
- Flow-through operation: 20
Temperature control
This viscometer has built-in thermoelectric heating and cooling (Peltier elements).
- For measurements between 5°C (41°F) up to 100°C (212°F) no additional thermostat is required.
- For measurements below 5°C (41°F) an additional circulation cooler is required for counter cooling.
Sample
- The microcapillaries allow for very low sample volume, starting from 0.1 mL.
- Typical sample volume: < 1 mL
- Suitable for transparent and opaque samples.
Standards and Norms
USP <913>, corresponds to DIN 53015 and ISO 12058
Overview
| Viscometer type | Rolling-Ball Microviscometer |
|---|---|
| Measuring principle | Rolling-Ball |
| Automatic | |
| Microviscometer | |
| Measured quantity | time |
| Calculated quantity | dynamic/kinematic viscosity (density required) |
| Viscosity range - min | 0.3 mPa.s |
| Viscosity range - max | 10,000 mPa.s |
| Temperature - min | -30°C |
| Temperature - max | +100°C |
| Liquid bath thermostat required | no (counter cooling for temperatures < 5 °C) |
| Temperature change with same filling | yes |
| Automation possible | yes |
| Sample volume - typical | starting from 0.1 mL / typ. 1.5 mL |
| Solvent volume - typical | manual: 5 mL / flow-through: 10 mL |
| Sample throughput - max / h | manual: 10 / flow-through: 20 |
| Measuring accuracy | < 1 % |
| Shear rate control | no |
| Shear rate calculation | yes |
| Lab space | < 0.25 m² |
| Standards and norms | USP <913>, corresponds to DIN 53015 and ISO 12058 |
We offer typical values which are based on the values in brochures and standards but are not related to specific instruments.