Determination of Coating Viscosity

Materials and Apparatus for Viscometry

The materials used in the paint viscosity measurement method include: paint samples, clean soft paper, paint thinner, etc. The instruments used to measure the paint viscosity include: mercury thermometer, temperature range 0-50 ℃, division at 0.1 ℃, stopwatch, The division is 0.2s, Tu-1 cup, Tu-4 cup, falling ball viscometer, permanent magnet, spirit level, 50ml or 150ml enamel cup, etc.

Sampling for Viscometry of Coatings

When taking materials, for the same product packaged in the same production plant, the sampling of every 10 barrels of products shall not be less than 2 barrels. Before sampling, fully stir the paint in the barrels of the product to be taken, then open the cover and take it out evenly as a test sample, and place it in a container.

Coating Viscosity Determination Method

Take Tu-4 viscometer as an example:

First, keep the sample temperature in the temperature range of 25±1°C. If the paint temperature is low, you can heat it up, otherwise, cool it down, and then measure the viscosity. For the determination method, please refer to the relevant methods and knowledge about viscosity determination in NBCHAO Mall. The average value of the difference between two determinations of each sample shall not be higher than 3%

Notes on Determination of Viscosity

If you use Tu-1 cup, the coating product whose measured viscosity should not be lower than 20s, Tu-4 viscometer measures the coating product whose viscosity is within 150s; the falling ball viscometer measures the coating product with relatively high viscosity transparent liquid.