Our rheometers are portable, stand-alone rotational viscometers based on a proven principle. They are characterized by the simplest handling and a large measuring range. All rheologically relevant parameters are displayed simultaneously and constantly updated. All measurement data is automatically stored internally and can be output later via PC.

Where are our viscometers used?

The R180 rheometer, for example, is designed for fast and reliable determination of viscosity in the laboratory and plant, especially for production and incoming goods inspection as well as quality assurance.

The areas of application are diverse, such as

– Paints and lacquers
– coatings
– foods
– pharmaceuticals
– cosmetics
– plastics
– chemical base materials and much more.

How do our viscometers work?

Our rheomats are classic rotational viscometers. The measuring bob rotates in a fixed measuring tube and is driven by a motor. The substance to be measured in the measuring gap generates frictional resistance, which is recorded via motor current measurement of the viscometer. The result is the viscosity of the substance. The measurement is carried out in the immersion method or in a closed and thus temperature-controlled system.

Measuring systems

The extensive system spectrum enables viscosity measurement of a wide variety of samples.

– Measuring systems according to DIN 53018 for the determination of absolute viscosity
– Measuring systems according to ISO 2555
– Relative measuring systems for control measurements
– Anchor stirrer measuring systems
– Cone-plate measuring systems
– Special measuring systems according to customer requirements.

Measurement

The measurement of the sample with our viscometers can be carried out directly in the container using the immersion method and offers the following advantages:

– Exact determination of the instantaneous viscosity
– no decanting of the sample
– minimal sample loss
– If the measuring tube is fitted with the appropriate sealing plug, small sample quantities can be thermostated and measured.

Standards

The three measuring systems according to DIN 53018 each consist of a measuring body, a measuring tube and a sealing plug. The radius ratios between the measuring body and the measuring tube are the same in each case and comply with the standard. Thus, measurements with these measuring systems can be compared with all other DIN-measured values.

Relative Measuring Systems

The measuring bodies of the DIN measuring systems can be used with a larger measuring tube or without any measuring tube at all. The measuring range of measuring systems used in this way is thus considerably extended (see table Measuring ranges). The values measured with these systems are relative viscosity values which can only be determined with measuring systems.

Temperature Detection

When determining viscosity, it is essential to record the temperature. This measurement is made by a built-in Pt100 – temperature sensor, which is placed directly in the sample above the measuring gap.

Anchor Agitator

Various products cannot be measured in a DIN system. These include substances with a high solids content or those that form layers under constant shear in the measuring gap of a coaxial system. For these applications, anchor stirrers are suitable as measuring bodies.

ISO Spindles

The measurement according to ISO 2555 is widely used and is possible with this inexpensive device much more accurate than usual. The ISO spindles are bell- or disc-shaped rotational bodies. Measurements are taken in a standard beaker or other vessel. Extension: By selecting from the wide range of optional accessories, you can optimally adapt your instrument to your application.

Software

The viscometers can be controlled via special PC software (system requirement: Windows). The measurement data can be transferred to the PC and analyzed according to various rheological evaluation methods.

Measuring procedure

Flow curves characterize the flow behavior of substances. The rheometers determine flow curves automatically or controlled via a PC. Up to fifty recorded rheograms are stored and then output via PC. Of course, measurement at constant shear stress is also possible.

Calibration

Regular calibration according to the manufacturer’s specifications guarantees the reliability of the measured values. The measurement inaccuracy is less than 1% of the current measured value. In accordance with DIN 53019, calibration is performed gravimetrically at the manufacturer. This should be renewed once a year. An additional check with standard liquids can be carried out and increases safety.