Which instrument is commonly used to check viscosity?

The Zahn Cup is a specific instrument designed to measure the viscosity of a liquid by determining the time it takes for the liquid to flow through an opening at the bottom of the cup. This type of cup is often used in paint technology and other applications where understanding the flow characteristics of a liquid is crucial. The measurement obtained is directly related to the viscosity, allowing for consistent and repeatable results, which is vital for formulating paint products that meet certain performance criteria.

While the viscometer is also a valid instrument for measuring viscosity, the Zahn Cup provides a quick and practical method especially suited for certain liquid applications, making it a favored choice in various industries, including coatings and paints. Other tools like a hydrometer are focused on measuring density rather than viscosity, while flow meters typically measure the rate of flow rather than the viscosity itself.