Principle of operation

The Viscomat is equipped of three separate glass viscometers, each furnished with a set of platinum electrodes for the measurement of the flow rate.

The three viscometer tubes are the core of the Viscomat .

The tubes in the Viscomat are of open capillary type, designed to fully comply with the design described in SCAN-CM 15 and ISO 5351. The measures are as defined in the standards, with a 1 mL volume on top of a 0.8 x 150 mm capillary. When opened to air for elution, the air flow is completely non-restricted. The capillaries ares connected to vacuum via a manually operated valve placed above the viscometer tube. The valve is turned to measurement position after a sample has been drawn up into the viscometer tube, above the upper electrode, using the vacuum.

The capillary is enclosed in a glassware water jacket, which is used for keeping the temperature constant at 25°C by connection to a constant-temperature bath at 25°C.

A typical Measurement routine for analyzing viscosity with Viscomat II:

• The samples are logged in the ViscLab software.
• Place the sample one at at time on the analytical balance and the weight is automatically transferred from the balance to the ViscLab 2 software.
• The sample is dissolved in water and CED, conditioned to 25°C and drawn into the capillary viscometer by turning the vacuum valve.
• The measurement starts when the level pass the top electrode and terminates at the lower electrode. The time signal is measured with high resolution and accuracy (0.1 ms), processed and the intrinsic viscosity (η) is then calculated with five digit accuracy. The results are compared against predefined alarm limits and displayed in the ViscLab 2 computer software, including instant alarm status. Results are stored in a database for archiving, export to eg. a LIMS or SCADA system, printing and further analysis and data handling.