In this article, we will explore some measuring and control instruments (such as the viscometer), which help verify the suitability of coatings and paints while making sure the properties meet the requirements of specific applications such as:
- Corrosion protection
- Protection of materials against degradation
- Thermal insulation
- Fireproof protection
- Electric insulation
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What is runoff time?
Flow or runoff time is a property that can give us an idea of the viscosity of a Newtonian fluid.
In other words, it’s a fluid whose viscosity does not vary with the speed at which it is measured.
By measuring the runoff time of a coating, it’s possible to determine its kinematic viscosity. This result informs as to its suitability for the desired application.
How do I measure runoff time? Kinematic viscosity
The most common way to control coating flow time is by means of flow cups.
As the name suggests, flow cups are cup-shaped tools, which are used to quickly determine the flow time and kinematic viscosity of Newtonian fluids.
The process of measuring the flow time when using a flow cup consists in verifying the time it takes for a Newtonian fluid to escape from the small orifice located at the base of the cup itself.
The advantages obtained by using flow cups to determine the flow time (kinematic viscosity) of a coating are:
- Simplicity and portability.
- Quick results.
- Any Newtonian fluid can be tested with accurate results.
Flow cups are normally classified according to reference standards.
The most common types include:
What are flow cups most commonly used for?
Flow cups are commonly used to check the physical characteristics of different coating materials such as paints, inks or lacquers.
As a result, almost any industry using these kids of coatings can benefit from the flow cups described so far.
However, the most common industries where they are used include:
- Food and drink
- Chemical products
What is the coating dynamic viscosity coefficient?
The dynamic viscosity coefficient of a coating represents the resistance value of the coating particles to movement or stress.
- Reduced costs that may result from adding unnecessary layers of coating.
- Reduced processing times.
- Increased productivity.
- Increased profitability.
How to measure the dynamic viscosity coefficient
The dynamic viscosity coefficient of a coating can be measured and controlled in several ways.
However, there is one instrument that excels beyond the others in terms of performance: it’s the digital rotary viscometer.
The digital rotary viscometer, like our SAVISC186 model, allows you to check the dynamic viscosity of the coating at a specific operating temperature.
This is important because temperature is one of the environmental aspects that can have the most impact on the viscosity of your coating.
The process of measuring the dynamic viscosity with a digital rotary viscosimeter starts by pouring a sample of the coating into a container and placing the container so that the spindle of the viscometer is inside the coating.
After that, the spindle rotates at a constant speed and the viscometer measures the torque value to determine the viscosity.
What are digital rotary viscometers most commonly used for?
Many industries depend on viscosity control and therefore use rotary viscometers.
Specifically, these types of tools are particularly useful when checking dynamic viscosity in non-Newtonian fluids.
The most common applications of rotary viscometers are found in the following industries:
- Oil and gas
- Chemical products
- Food and drink
- Laboratory testing
- Scientific research
How to choose the right instrument?
Choosing the right instrument for checking the physical characteristics of coatings is essential to ensure accurate results and the correct coating application.
To make the best choice, it’s important to consider several factors including:
- Type of coating material (Newtonian or non-Newtonian).
- Standard used for the measurement.
- Whether temperature control is necessary.
- The need for portability.
[Video] How to measure the viscosity? Viscosimeter – SAMA Tools
SAMA Tools is a trusted brand for the purchase of instruments used for checking the physical characteristics of coatings. We offer a wide range of quality products, suitable for all needs and at affordable prices. Furthermore, we are committed to providing the best possible experience for all our customers, with pre, during and post sales assistance.