Molasses flow meters are a type of flow meter used for molasses flow measurement. Molasses are common high viscosity liquids. So Molasses flow meters are flow meters that can be used to measure various high viscosity liquids. Can common electromagnetic flowmeters be used to measure high viscosity liquids? What about the Coriolis mass flow meter?

Perhaps after the introduction of this article, you will understand.

Molasses Flow Meters-High Viscosity Liquids Solution

Viscosity is a value obtained by measuring the inherent frictional force of a fluid.
Viscosity is a physical and chemical property of a substance.
It is defined as a pair of parallel plates with an area of A and a distance of dr. The plates are filled with a certain liquid. Now a thrust force F is applied to the upper plate to generate the force required for a degree of speed change.
Due to the effect of viscosity, the object is subjected to frictional resistance and differential pressure resistance when moving in the fluid, resulting in loss of mechanical energy.
Essentially, the more viscous a liquid is and the more resistant it is to flow, the higher its viscosity.

Due to the viscosity of the liquid, this force layer is transmitted layer by layer. Each layer of liquid also moves accordingly. A velocity gradient du/dr is formed. Called the shear rate, expressed by r’.
F/A is called the shear stress and is represented by τ.
The relationship between shear rate and shear stress is as follows:


The proportional coefficient η is defined as the shear viscosity of the liquid.
In addition, extensional viscosity and shear viscosity are usually used more often. Generally speaking, when it is abbreviated as viscosity without distinction, it usually refers to shear viscosity.

Therefore, η=(F/A)/(du/dr)=τ/r′.

Immerse two plates with an area of ​​1 square meter in the liquid, and the distance between the two plates is 1 meter. If a 1N shear stress is applied to a certain board. If the relative speed between the two plates is 1m/s, the viscosity of the liquid is 1Pa·s.

Newtonian fluid:

a fluid that conforms to Newton’s formula. Viscosity is only related to temperature, not to shear rate.

Extended reading: Fluid flow meter types

Non-Newtonian fluid:

does not conform to the Newtonian formula τ/D=f(D). Express the viscosity under a certain (τ/D) with ηa, which is called the apparent viscosity.

Viscosity changes significantly with temperature but usually changes little with pressure.

Liquid viscosity decreases with increasing temperature, while gas viscosity increases with increasing temperature.

For solutions, the relative viscosity μr is often used to indicate the ratio of the solution viscosity μ and the solvent viscosity μ. which is:
The relationship between relative viscosity and concentration C can be expressed as:


In the formula, [μ] is the intrinsic viscosity of the solution.

K’ is the coefficient. [Μ], K’have nothing to do with concentration.

The viscosity of different fluids varies greatly.

At a pressure of 101.325kPa and a temperature of 20°C, the dynamic viscosity and kinematic viscosity of air, water and glycerin are:

Air μ=17.9×10^-6Pa·s, v=14.8×10^-6m²/s
Water μ=1.01×10^-3Pa·s, v=1.01×10^-6m²/s
Glycerin μ=1.499Pa·s, v=1.19×10^-3m²/s

More about Viscosity

You may find examples of high and low viscosity fluids- Honey, syrup, glue

Dynamic viscosity unit conversion

1 poise (1P)=100 centipoise (100cP)
1 centipoise (1cP) = 1 mPa·s (1mPa·s)
1 mPa·s (1mPa·s)=1000 microPascal·s (1000μPa·s)

Conversion of dynamic viscosity and kinematic viscosity
Where μ--- dynamic viscosity of sample (mPa·s)
ν--- Kinematic viscosity of sample (mm²/s)
ρ--- The density of the sample at the same temperature as the measured kinematic viscosity (g/cm³)

Extended reading: Liquid mass flow controller for process liquid -Sino-Inst

The so-called high-viscosity liquid means that the liquid is viscous and thick. It is different from general liquids and non-Newtonian fluids (mud, pulp). The activity is slow and it is very difficult to filter with simple methods.

What’s more, the liquid contains some dust in addition to it. It also contains colloidal particles that are not completely dissolved.

For example solutions of rubber, paraffin, cellulose acetate, viscose, polyacrylonitrile, paint and animal glue.

Read more about: Coriolis Mass Flowmeter Working Principle

Properties of molasses

What is molasses:

Molasses is a viscous, dark brown, semi-liquid object. It mainly contains sucrose. The content of pantothenic acid in sucrose is higher, reaching 37mg/kg. In addition, the biotin content is also considerable. It is easy to be mixed into soybean molasses and molasses fermentation liquid.

Molasses characteristics

  1. Molasses is a brownish yellow viscous liquid, with the fragrance of yeast and the sweetness of molasses;
  2. The content of CP is high, 3-6%;
  3. High sugar content, generally 42-50%. Low energy density, good taste. Fast digestion and absorption, and the price is lower than corn (2346, 2.00, 0.09%).
  4. Contain vitamins, minerals, bacterial proteins, nucleic acids, surface active substances and growth-promoting factors (biologically active substances) and other ingredients.
  5. Anti-acid and alkali, anti-oxidation, strong chelating ability to divalent cations. It can form organic chelating trace elements with metal ions. Promote the absorption and utilization of minerals by livestock and poultry.

The above is a detailed introduction to what molasses is.

Choosing right molasses flow meters

For the properties of molasses. There are 4 types of flow meters that can be used as molasses flow meters.

The electromagnetic flowmeter is a flow measuring instrument. In the working conditions that require flow measurement, electromagnetic flowmeters are inseparable.

When measuring the flow of low-viscosity and high-viscosity liquids, many people think of electromagnetic flowmeters. In fact, it is right, although I dare not say that the electromagnetic flowmeter is omnipotent. But almost all conductive liquids can be solved by electromagnetic flowmeters.

For diluted molasses. Good liquidity. It can be measured with an electromagnetic flowmeter.

Extended reading: Sludge flow meter for sewage treatment return activated sludge system

Spur Gear Flowmeter is our brand new product. Measure small flow rates. As low as 0.01L/min.

The gear flow meter is a common positive displacement flow meter. The gear flow sensor has built-in double gears to operate. The volume of the medium is calculated by the volume of the gear. The flow rate of the small fluid medium is measured.

Gear flow meters can be used for resin and glue flow measurement. Flow measurement of hydraulic oil, lubricating oil, and grease. Maltose, syrup. Fuel oil flow measurement. Flow measurement of ink and asphalt. Flow measurement of liquid nitrogen, freezing liquid, and solvent. Edible oil, fish oil, and food filling measurement. Chemical and anti-corrosion requirements fluid measurement. A fluid quantitative control system, etc.

Read more about Gear flow meter for Microflow

If the flow rate of molasses is large, how to measure the flow rate of the liquid with high viscosity?

Oval gear flowmeter is a positive displacement flowmeter, also known as displacement flowmeter. It is a type of flowmeter with high measurement accuracy among flow meters, and it is very good at measuring liquids with high viscosity.

The oval gear flowmeter can measure liquids up to Viscosity: 1000-2000mPa.s.

LCD display Oval Gear High Viscosity Flow Meter

The measurement of the oval gear flowmeter has nothing to do with the flow state of the fluid. The higher the viscosity of the medium, the smaller the leakage from the gear and the metering gap. Therefore, the higher the viscosity, the more advantageous it is for measurement.
Measurable medium: fuel, diesel, gasoline, heat transfer oil, hydraulic oil, kerosene, tar, petroleum, crude oil, asphalt, resin, and other liquids. Especially suitable for the measurement of high viscosity liquids.

Coriolis mass flowmeter has the characteristics of high measurement accuracy, good stability, and easy operation. It is an ideal instrument for measuring the flow of high-viscosity media such as high temperature, high viscosity, and easy crystallization.

The flow and temperature of the high-viscosity medium form a cascade control system. Install an automatic regulating valve on the inlet pipe to automatically cut off and adjust the size of the oil volume according to the reaction temperature. Ensure a fast response state and reduce pure lag time.

After using the mass flowmeter, the flow of the high-viscosity medium is uniform and stable, which reduces the labor intensity of the operators. The pure lag time is shortened, and the quality of the product is guaranteed. Improved economic efficiency.

Extended reading: U-series Liquid Mass Flow Meter | Liquid-slurry flow measure

Related blogs:

Low Flow Meters

What is a low flow meter? Low Flow Meters refer to those flow meters that…

Grease Flow Meters

What is a Grease Flow Meter? Grease Flow meters are meters dedicated to measuring the…

Solvent flow meters

The solvent flow meter is a flow meter that can measure solvent volume or mass…

Mechanical Flow Meters

Selection Guide What is a mechanical flow meter? Mechanical flow meters are a type of…

Sino-Inst, Manufacturer for Molasses Flow Meters-High Viscosity Liquids Solution

Sino-Inst’s Molasses Flow Meters, made in China, Having good Quality, With better price. Our flow measurement instruments are widely used in China, India, Pakistan, the US, and other countries.