What is an industrial agitator?
As with all industrial equipment, agitators or mixers are made with different components to operate in the right way. Each one of these must be selected by knowing some of its features, like work environment, product to be mixed, and container, among some others.
In consideration of all these elements and information, we can determine components’ mechanical and energetic capacities, as well as their dimensions. Next, we’ll review industrial agitator definition, the makeup components, and the function that industrial mixers systems achieve. Let’s start by explaining: What is an industrial agitator?
An industrial agitator, also known as a mixer, is a mechanical device, in charge of performing agitation and mixing operations to generating movement in a fluid to obtain certain properties. Industrial agitators’ applications and uses include some of the ones in the next list:
- Homogenization: agitation of two substances until a mixture with the same properties is obtained.
- Suspension: consists of a solid’s dispersion into a liquid medium.
- Emulsion: a mixture of two incompatible liquids until reaching a result that is homogeneous as possible.
- Dispersion: the action of dissipating gas into fluids.
- Neutralization: the chemical reaction between an acid and basic solutions.
- Crystallization: forms crystals from a different phase of the material (usually liquid).
- Fermentation: The mixture obtains nutrients from microorganisms through suspension.
If you want to know more about these processes, you can read the article "Industrial agitation solutions"
We can now move-on in to knowing the agitator’s components and quickly reviewing them and their particularities.
Industrial agitators’ components
The industrial mixer is composed of different pieces that allow doing functions such as a power unit, fastening and sealing options, bushings, shaft, and mobiles or impellers.
We will explain all in the next paragraphs.
First, we’ll discuss the power unit, which is responsible for the equipment rotation. It consists of a motor and, in most cases, a gearbox. The gearbox selection will determine the agitator’s force and rotational speed.
Start with the motor or power unit, defined as a machine that transforms energy into rotational motion, and it’s a fundamental part of the components of an industrial agitator.
Related to the agitation processes, there are two types depending on the energy that applies to them.
- Alternating current motors: use electrical energy to function.
- Pneumatic motors: whose characteristic lies in the way in which they are injected and compressed air to function.
The first type is the usual for industrial agitators due to its versatility and, compared to others, lower cost. However, regarding pneumatic motors, it’s preferable to use them in situations where there is already a previous infrastructure, or when access to electricity is not easy.
When we talk about the reducer or gearbox, then, we will define it as a gear transmission system; its function is to decrease the rotary speed delivered by the motor, to increase the torque.
In addition, there are three settings depending on the input position and the available space for the gearbox:
- Coaxial reducer: where the shaft is concentric to the shaft of the reducer and is used in small equipment.
- Bevel gear reducer: both shafts are positioned perpendicular to the shaft and commonly used in tight spaces situations or on horizontal input equipment.
- Parallel shaft reducer: in which the shafts are parallel, it’s the standard configuration in medium and large equipment.
The next agitator component is the fastening system, which keeps the equipment in the product container. Some simple ones, such as a clamp or support for IBC/GRG containers. In addition, the personalized manufactured plate can be attached to any entrance.
The fastening system has a flange, which is a piece usually made of stainless steel and carbon. We must mention that the ANSI rules standardize this flange, so most of the tanks have adaptable inlets.
We can add a lantern if we want to install the couplings or the sealing system outside the tank.
Find the ideal agitator’s components for your processes with Autmix Flow.
The sealing system is an agitator component for keeping the product inside the container. So, when choosing this element for an industrial agitator, we must decide based on the mixing task.
For example, when working with vertical agitators, where it's required to maintain a tight gas or provide better protection against external agents, you can opt for an industrial seal.
Likewise, a mechanical seal is usually installed in the case of a bottom or horizontal agitator, where processes require significant tightness due to fluid pressure.
This works from a static and rotating face, where it can lubricate with the fluid. If we wish to accompany the seal with additional protection, it is possible to install cable glands.
On other hand, the seals are agitator elements that are classified in two types depending on the function:
- Double sealing
- Cartridge sealing
To know more about this topic, please read sealing and mounting options.
Shaft-motor or shaft-reducer coupling
The coupling is another of the agitator components and aims to keep the shaft fixed and rotate in tandem with the power unit.
In the case of working with smaller equipment, that does not have a reducer, assembly by pinch valves and stud bolts. In the coupling, both shafts are embedded in a piece machined to measure, and pressure is exerted by small cylinders called oppressors.
For this reason, when adding a bearing, we must also add a turret over the pinch valve. If the shaft is coupled to a coaxial reducer, you can use the previous system or a bearing shaft. This one consists of adding a flange to the shaft ends and securing with bolts and nuts.
The process is different when working with a large or medium size gearbox, like the parallel shafts or bevel gears. These have a hole to which we must attach the agitator shaft, and there are two methods.
The first one is with the bold and washer system, and it consists of bolting one shaft end to the reducer and using a key for preventing the rotation on its own.
On the other hand, in the second method, there is a shrink disk coupling a similar procedure, the only difference being that a disk is screwed around to fix the shaft.
Another agitator component is the shaft, which can be defined as the backbone of this kind of equipment. This component has the main objective of supporting the mobile and transmitting rotation to it from the power unit.
One significant thing to remember when manufacturing or requesting an agitation system is that the shaft must be rigid, stable, and concentric. To achieve this, in the case of a tubular one, the diameter and thickness must be calculated, concerning the loads received, due to the combination of forces generated by the impeller rotation.
We reduce the flex capacity of the shaft under a load, avoiding the reduction in the mixing efficiency. As additional information, we must know that the ends of the shaft are customized based on the coupling that will be used.
There are multiple coupling types for the shaft, depending on the application that will be carried out. One is lugs, where each blade is screwed with tabs previously welded to the shaft.
In the same way, there is the welded mechanical core, a system made up of three pieces with blades welded and screwed together around the impeller.
However, the most popular couplings are made with a bushing in between. This is a tubular-shaped component, to which the impeller blades are welded and mounted in different ways to the shaft.
Welding is a way of joining the shaft to the mobile, and it's recommended in cases where safety and hygiene are the priority. We offer the option of joining by valves, in which all the elements fix both parties.
Finally, we have the wedge coupling, where the bushing is bolted to the shaft, and the wrench is inserted to prevent its rotation.
Mobiles, drivers, or profiles
And now, we need to discuss the profiles or impellers as agitators' components, and we will define them as elements that carry out the mixing process. These must be selected based on the product to be mixed and the process that will be carried out. From this information we can determine if the flow will be axial, parallel to the shaft; or radial, perpendicular to the shaft.
There are even models capable of generating mixed flow, such as the marine impeller.
For choosing an agitation system, we need to consider the result that we want to achieve. For example, suppose we are working with a highly viscous product. In that case, we can apply two different effects: slow the movement with an anchor agitator or reduce the viscosity with a Cowles disc impeller, that generate stress shear. If you want to know how stress shear works, read more in this article.
Also, we must consider the relationship between power consumption and pumping capacity, mainly when selecting an axial profile impeller. Similarly, there is the ability to add some plugins to increase efficiency, such as scrapper or turbulent fingers.
Reviewing all these topics, each industrial agitator component plays an essential role in the mixing process. Thus, we in Autmix Flow, must choose every component carefully and think of the best possible result.