This type of pump is one of the oldest. The mechanical displacement of a liquid medium can be called the simplest implementation of the pumping principle. Today, the designs of such units, of course, have a more complex device compared to the first representatives of the class. In its modern form, the piston liquid pump has a robust housing, a well-developed element base and assumes the availability of wide possibilities for communication. The latter aspect determines the distribution of equipment in various fields from domestic needs and up to industrial highly specialized industries.
Pump device
The base of the unit is a metal cylinder, in which working processes with liquid take place. Physical manipulation is performed by a piston in which valves are provided. Specialists also call such a plunger system - according to the type of piston mechanisms used. In essence, the main function in such systems is performed by a hydraulic press. The piston liquid pump operates on the principle of reciprocating motion, although it differs from classical hydraulic motors by the presence of a valve distribution system. The drive structure also includes a range of service parts and components. The parts of this design include the crank and connecting rod, which form the basis of the already working working body.
Operating principle
In a simplified form, the function of such aggregates resembles a regular syringe or intake column, in which the carrier is replaced by a valve. But, there are also features that a piston liquid pump has. The principle of operation in this case provides that the receiving pipe will also have a closing valve. Thanks to such a device, liquid cannot flow back into the cylinder.
Despite the simple flowchart, there is one significant drawback of such pumps. The fact is that the reciprocating action does not imply a uniform and smooth delivery of the medium. The abrupt pace at which the piston liquid pump operates can be difficult for subsequent servicing of the receiving communications. However, the use of multiple pistons can minimize this drawback.
Double Action Models
The appearance of this kind of piston pumps is due to the desire of manufacturers to eliminate the ripple effect, which occurs precisely because of the rhythm in which the piston pushes portions of the liquid. In such pumps, the rod and piston cavities have individual valve systems. This principle of distribution of water supply allows not only to eliminate ripple, but also to increase productivity. True, single-sided liquid piston pumps still have their advantages, which are expressed in a higher degree of reliability and durability. Another modification that was supposed to eliminate the rhythmic flow of fluid is a pump, supplemented by a hydraulic accumulator. At the time of peak pressure, such aggregates collect energy, and when it decreases, on the contrary, they give up. However, it is not always possible to completely eliminate the pulsation, and operating enterprises have to accordingly develop fluid intake configurations already outside the pump design.
Purpose of pumps
Use such units in different areas. Its principle of action does not involve working with large volumes of media, but it has many other useful qualities. Since during the displacement of each new “dose” by the piston, a new fluid is received in a dry cylinder, the use of the design justifies itself in the chemical industry. The specialized purpose of piston liquid pumps allows operation with aggressive media, explosive mixtures and some types of fuel. But this is not limited to the use of piston units. They are also used for domestic purposes, to supply clean water and irrigation. Again, such models are not designed for large volumes of circulation, but they are distinguished by their reliability and delicate handling of the fluid being served - in fact, this factor caused the widespread distribution of pumps in the food industry.
Advantages and disadvantages of construction
Among the advantages of such systems can be noted the endurance of the structure. This is due not only to the use of high-strength materials for the manufacture of components, but also to the principle of operation. In addition, the piston liquid pump is distinguished by the ability to work with carriers that have high requirements for starting conditions. In particular, many experts note the benefits of “dry” suction, which not every pump can provide. As for the disadvantages, they mainly relate to low productivity. Of course, it is theoretically possible to expand the technical parameters of the unit, but this will lead to an increase in the operational requirements of the equipment. Moreover, many alternative designs are able to provide sufficient productivity at a lower cost.
Conclusion
Pumps of this type occupy a separate place in the market, while satisfying the needs of private users and the needs of large enterprises. In modern versions, a piston liquid pump allows you to perform a wide range of tasks. Some of them may well implement units of a different type, but there are areas in which it is impossible to do without the hydraulic principle of pumping. This applies to the mentioned chemical and food industries. On the other hand, the demand for piston pumps in everyday life is due to their simple design and undemanding maintenance. And this is not to mention the high operational resource of this equipment.