Modern engineering has reached certain heights. Constantly developing more and more technical products that simplify or optimize a particular process. This article will focus on pumping devices, in particular, what is a peristaltic pump. The product is quite interesting and currently necessary. Let's talk about everything in order and deal with its purpose, the principle of work and other interesting points.
General information
A peristaltic pump is needed for pumping various fluids that move along curved tubes. Briefly, the essence of the device can be described as follows: there are special rollers that squeeze the tube in a specific place. Moving along it, they push the fluid to its destination. The entire structure consists of a small number of elements: a flexible hose or tube, rollers and track (pressure surface). Although it is often possible to meet models that do not have a clamping surface. The track can not be used if you create the proper tension of the tube around the roller. Despite such a simple design, it is quite difficult to make such a pump yourself. This is due to the fact that it is necessary to comply with a number of requirements related to working with viscous fluids, but we will talk about this a little later.
In more detail about the principle of work
We have already figured out a bit what a peristaltic pump is. It is worth paying your attention to the fact that this device is often used not because of its expediency, but since there is no other way out. So, a peristaltic metering pump is often used. It is easy to guess that the main function of such a unit is to supply measured quantities of liquid to the working unit of any equipment.
It is on the peristaltic principle that the work of the intestines, both human and animal, is based. The key difference is that in a living organism, muscle contraction takes place, creating pressure on the walls of the fluid. In the case of the pump, the movement is provided by special rollers. They push the viscous substance in the course of its movement in certain portions. By the way, the peristaltic pump dispenser has a very narrow scope.
A little more about product design
As noted above, a positive displacement pump can be manufactured at home. But to do this is not so simple, despite the elementary design. In particular, because special tubes for peristaltic pumps, as well as rollers, will be needed. It is desirable to bend the working hose into a C-shape, which will allow you to effectively place the rollers. The latter are mounted on a rotating rotor, which gives them movement at a given speed. When the roller rotates, it presses the hose against the housing, squeezing the fluid. Accordingly, a vacuum is created behind the second blade. After the end of the cycle (full circle), the shape of the tube is restored to its original state. To simplify the design and not use a non-return valve, the peristaltic pump is equipped with two rollers that do not allow fluid to go in the opposite direction.
About scope
As noted above, a peristaltic metering pump is not used as often. The narrow scope is due to the material of the walls of the tubes, which must be flexible. This does not allow to distill hot liquids. Typically, the maximum operating temperature should not exceed 90 degrees Celsius. That is why such pumps are very rarely used in the organization of individual heating. After all, it is necessary to additionally install sensors for monitoring the temperature of the medium.
As for the pressure, then there are some limitations. This parameter must not exceed 16 bar. The key feature is that during pumping, the liquid does not come into contact with mechanical devices and metal surfaces. Therefore, pumps of this type are used where it is extremely important to maintain the purity of a viscous substance. In addition, the equipment is effective when working in an aggressive environment. The scope of use is usually limited to the food, chemical and pharmaceutical industries.
About the benefits of peristaltic pumps
One of the main strengths is that such equipment can be used as dispensers. This is due to the fact that for each revolution, the roller pumps a fixed amount of liquid. In addition, fluid only contacts the inside of the hose. This allows the use of pumps in medicine and the food industry. But it is worthwhile to understand that hoses for peristaltic pumps must be from a certain material (non-toxic).
Another strength of such pumps is that due to the absence of turbulence, the structure of the fluid does not change. The pumped substance often contains abrasive particles. Some pumps cannot distill such substances, and for equipment of this type this is not a problem. It should also be noted that nothing will happen to the peristaltic pump if it runs dry, that is, in the absence of fluid in the hoses.
Pump types
Monoblock devices exist. They represent a single structure enclosed in a housing. It houses the engine, gearbox, and adjustment units. The solution is good because the pump does not take up much space, but its maintenance is somewhat difficult.
There are also modular designs. It is easy to guess that such peristaltic hose pumps consist of several parts. They take up more space, but are much easier to repair, since it is not necessary to disassemble the entire pump to replace a particular unit.
In addition, peristaltic pumps are usually classified according to the number of rollers. The more of them, the more uniform the movement of the liquid. The maximum number of rollers is 8 pieces. At the same time, the price of such equipment is quite high. But if accurate dosage is required, then a pump with a large number of rollers is needed.
DIY peristaltic pump
At the first stage, you need to choose the right tube. Although if the purity of the pumped liquid does not really matter to you, then not everything is so bad. But do not forget that productivity depends on the inner diameter of the hose. Such materials are often used: bioprene and marprene, as well as silicone and neoprene. Hoses can be made continuous or with fasteners that allow them to be fixed motionless.
Then you can assemble the peristaltic pump with your own hands. We use rollers of the required diameter, which you will have to buy in the store. It is better to set them in motion with the help of an electric motor through a shaft or a belt drive. Around the rollers we pull the tube and mount the whole thing in the case. One end of the hose is placed in a container from which fluid is drawn, and the other at the destination. Pay attention to the fact that the rollers evenly dispense the liquid during operation, unless, of course, this is important. In principle, there is nothing complicated. The main thing is to build a high-quality pump that will satisfy its operational characteristics. As an engine, you can use an electric motor of low power. It is extremely important to consider the diameter of the tube.
About designation and configuration
Like any other pumping equipment, this is supplied as a kit. Usually there is a special passport on which the equipment is indicated. The technical specifications of the equipment are also indicated there. If you are going to buy a laboratory peristaltic pump, then pay attention to such parameters as the type of impeller and the number of rollers. We have already figured out that the more videos, the better, but the equipment becomes more expensive due to its complexity.
The type and diameter of the hose matters. The scope depends on the material, and productivity depends on the diameter. In the end, there is such a parameter as power. In many cases, it is the main one and determines the effectiveness of the equipment as a whole.
To ensure a more comfortable use of such pumps, you can buy additional components. If you assemble the pump in your workshop, then set the rotor speed control. This will allow you to control the speed of rotation of the rollers, and hence the performance.
Pump models
Home-made equipment practically does not require any investments, but often such a pump does not satisfy technical needs. Therefore, it is advisable to buy a ready-made pump, even if not the most expensive and productive. A vivid example of quality and affordable price is the Etatron F pump. It is capable of distilling just 2.2 liters of viscous liquid in an hour. The price of such a purchase is about 4 thousand rubles. This is a very compact equipment that takes up very little space and can be installed anywhere. Such a small pump is enough to establish a small food production.
About service
Any infusion peristaltic pump is good in that it practically does not require maintenance. The number of wearing units and parts in this case is minimal. The flexible tube undergoes the most intense wear. Perhaps it is for the entire period of work that will have to be changed once. However, this is not a very expensive element, due to the wide range of materials suitable for its manufacture, for example, silicone. Although you can always experiment with replacing the hose.
Conclusion
So we talked about what a peristaltic pump is. This is pretty interesting equipment. The simple design, as well as the durability of parts makes such pumps very economically advantageous. But you must understand that using them to ensure water supply in the house or for sewage is not practical. To do this, they have long since come up with more efficient equipment with which practically no problems arise. Basically, now you also know how to make the simplest pump at home. This is not so difficult and does not take much time and effort.