Professional Stormer KU Viscometer – Technical Description:

This professional Stormer KU viscometer is a standardized Viscometer for determining the consistency and flow behavior of paints, coatings and related non-Newtonian materials, expressed in Krebs units (KU). Design and measuring principle fully comply with ASTM D562 and the relevant DIN EN ISO testing standards, which are the definitive standards for the Krebs scale and the associated test method.
This precision KU viscometer is used in R&D laboratories, production environments, and quality assurance systems where reproducibility, batch consistency, and regulatory compliance are critical.

1. Measuring principle

This Precision Stormer Viscometer works according to the Constant torque / variable speed principle:

• A precision-machined Paddle rotor (KU-spindle) is immersed in the coating sample.
• The device applies a constant driving torque.
• The rotational speed achieved at this moment is measured.
• The speed is converted to:

           i) Krebs Units (KU) – primary output scale

           ii) Gram (g) – Load to maintain rotation

           iii) Centipoise (cP) – approximate viscosity value for guidance

• Since the torque is constant, this precision Stormer viscometer directly reflects the deformation resistance of the material—which is particularly relevant for shear-thinning, non-Newtonian coatings.

2. Materials and Systems for Cable Fault Location

This Precision Stormer KU Viscometer is specially designed for architectural and industrial coatings with non-Newtonian behavior at low shear rates. Typical applications:

• Emulsion paints (interior/exterior)
• Water-based coatings
• Acrylate emulsions
• Alkyd resin paints
• Primers and undercoats
• Paints and sealants
• Printing inks (selected systems)
• Binders and intermediates

These materials require precise viscosity control to ensure:

• good spreadability and rollability
• even application
• stable stability
• defined flow and leveling behavior
• reproducible layer structure

The KU scale is optimized for these properties and correlates well with practical application behavior.

3. Deployment in Production and Quality Assurance

In manufacturing, this precision KU viscometer is used for:

a. Batch control

Each batch is compared against a defined target KU range. Deviations indicate:

• incorrect pigment volume concentration
• incorrect binder content
• solvent imbalance
• incomplete dispersion

b. Monitoring of raw material variability

Changes in:

• resin viscosity
• wetting agent effect
• thickener efficiency

are recognized quickly.

c. Control of dilution and adjustment processes

Water or solvent additions are specifically adjusted to achieve the target KU value.

d. Support for process adjustments

Viscosity trends provide indications of:

• Temperature influences
• shear history
• Polymer hydration
• Activation of thickeners

e. Documentation for customers and authorities

Many specifications require a viscosity specification in KU.

4. Device Configuration and Operating Conditions

Proper application includes:

Sample preparation

• Homogenize sample without introducing air
• Conditioning at 23 ± 2 °C (unless otherwise specified)
• Ensure sufficient sample depth for complete immersion of the KU spindle

Device setting

• Level device precisely
• Clean and correctly assemble spindle
• Check free rotation without mechanical friction

Measurement procedure

• Plunge ball screw spindle to reference depth
• Start device and wait for stabilization
• Record steady-state KU, g, and cP values

Calibration and Verification

Even though this professional Stormer viscometer does not require frequent calibration, good laboratory practice includes:

• regular verification with certified KU calibration oils
• Dimensional inspection of the ball screw spindle and the stainless steel sample cup
• Inspection of the drive mechanism for wear

5. Interpretation of the Results

The KU values provide a functional viscosity index:

• 40–60 KU → low-viscosity, high-flow coatings
• 60–80 KU → Standard emulsion paints
• 80–110 KU → high-build or high-strength systems

Since the Cancer scale Since it is nonlinear, even small changes in KU can result in significant differences in flow behavior.

6. Advantages of the Stormer-KU Method and This Precision KU Viscometer

• high reproducibility in non-Newtonian materials
• direct correlation with practical application behavior
• Easy to use, ideal for production environments
• standardized method (ASTM D562) for laboratory comparability
• low sensitivity to operator input compared to dispensing cups

These features make this professional Krebs-Stormer viscometer an essential piece of equipment in the coatings industry.