This is the linear velocity of the mobile at the blade extremity. It is calculated for all mobiles (radial, axial or tangential flow).

This is the speed at which the agitation rotor turns. It is generally expressed in rpm.

This is the fluid flow rate generated in the agitation mobile’s cross-section. It depends on the flow rate number, Nq (characteristic related to the mobile’s profile), the rotation speed and the diameter of the mobile used.

ATEX Zones- Classification of explosive zones

GAS ZONES (Directive 1999/92/EC) > Zone O : A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is present continuously or for long periods or frequently. > Zone 1 : A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is likely to occur in normal operation occasionally. > Zone 2 : A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is not likely to occur in normal operation but, if it does occur, will persist for a short period only.

DUST ZONES (Directive 1999/92/EC)

> Zone 20 : A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is present continuously, or for long periods or frequently. > Zone 21 : A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is likely to occur in normal operation occasionally. > Zone 22 : A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is not likely to occur in normal operation but, if it does occur, will persist for a short period only.

This is the mean velocity of the fluid in the cross-section swept by the mobile. It is calculated only for axial-flow mobiles (propeller, TT, TTP) and the radial-flow Rushton turbine.

Viscosity

Defines a fluid’s flow resistance. In the metric system, absolute viscosity is expressed in poise.

Absolute viscosity

The same meaning as the word viscosity used alone, to distinguish from empirical viscosity or kinematic viscosity. This represents the ratio of a fluid’s shear stress to its velocity gradient. It is a fluid’s internal flow resistance. Its unit of measure is the poise. The absolute viscosity divided by the fluid’s density gives the kinematic viscosity. This is sometimes also called dynamic viscosity. Absolute viscosity and kinematic viscosity are expressed in fundamental units. Empirical viscosity, like Saybolt viscosity, is expressed in arbitrary units of time, usually seconds.

Kinematic viscosity

This is the time required by an oil to flow through a capillary tube under the force of gravity. The unit of kinematic viscosity is the stoke or the centistoke (1/100 of a stoke). Kinematic viscosity is defined as the quotient of a fluid’s absolute viscosity in centipoises over its specific gravity, both measured at the same temperature.

This type of agitation mobile is used for the dispersion of powders when high shear forces are required, for example, in the field of paints for pigment dispersion. The dispersion turbine (or deflocculation turbine) is used with peripheral speeds of between 10 and 25 m/s.

Storage containers are sometimes equipped with an agitator which keeps solids in suspension before using during process.


Mixel has designed a special galvanised steel holder for 1000 litres standard containers.

This is a cast-iron or welded part allowing the placement of the seal system and/or bearings that guide the agitation shaft.
The raising support is located between the motor and the agitator securing flange.