Ubbelohde DIN Viscometers
Compliant with UNI 400313, ASTM D445-D446, ASTM 2515 and ISO 3104-3105 standards
Ubbelohde capillary viscometers are designed for the determination of the kinematic viscosity of liquids by measuring the flow time of the sample through a calibrated capillary at a controlled temperature.
They comply with UNE 400313, DIN 51562 Part 1 and ISO 3105 standards.
They are particularly suitable for quality control and research laboratories, as well as for petrochemical applications, lubricants, oils, solvents, and the characterization of the kinematic viscosity of fluids over a wide range of values.
The operating principle is based on the flow of the sample through a calibrated capillary under the action of gravity. Measurements are normally carried out using a thermostatic bath in order to maintain both the viscometer and the sample at the temperature specified by the test method.
The measured flow time is multiplied by the calibration constant of the viscometer to obtain the kinematic viscosity value, expressed in mm²/s or centistokes (cSt).
Main features
- Type: Ubbelohde capillary viscometer
- Version: DIN
- Application: determination of kinematic viscosity
- Measured parameter: kinematic viscosity
- Measuring principle: gravity capillary flow
- Unit of measurement: mm²/s (cSt)
- For use with a temperature-controlled thermostatic bath
- Compliance: UNE 400313, DIN 51562 Part 1, ISO 3105
- Available in different Types and viscosity ranges
The Type identifies the capillary configuration and the corresponding measurable viscosity range. Types intended for the lower ranges are used for low-viscosity fluids, while subsequent configurations progressively extend the measuring range to samples characterized by higher viscosity.
The availability of different configurations therefore allows the most suitable viscometer to be selected according to the characteristics of the sample and the expected viscosity range.
Scientific blown glassware is manufactured through hot working of borosilicate glass, a material particularly suited to laboratory applications due to its high thermal and chemical resistance and excellent resistance to thermal shock. Shaping is carried out by localized flame heating, controlled rotation of the glass, and air blowing to obtain precise geometries, uniform wall thickness, and smooth transitions with minimal internal stress.
The main processing techniques include blowing, drawing, constriction, expansion, glass-to-glass sealing, and the manufacture of standard ground joints, connectors, hose connections, stopcocks, and special fittings. Particular attention is paid to concentricity, wall thickness uniformity, and the continuity of welded joints, all of which are essential for reliable performance during heating, vacuum operation, and fluid transfer.
After forming, the glassware undergoes controlled annealing to reduce internal stresses generated during hot working. This process improves mechanical stability and resistance to thermal shock, making the glassware suitable for both standard laboratory applications and custom-designed experimental systems.