Suitable for
— Pure water. Pure water pumps conventionally include all models for which the maximum particle size (see below) does not exceed 5 mm; in addition, the permissible content of mechanical impurities (also see below) for them is also small. Accordingly, many of these models are capable of pumping water with impurities normally, but they are not suitable for heavily contaminated liquids.
— Dirty water. This category includes pumps capable of working with large mechanical impurities — more than 5 mm. Note that some manufacturers position such models as mixed-use units, “for dirty and clean water”. However, they have a reinforced design, the presence of a grinder capable of grinding the particles mentioned, a reinforced body, an increased diameter of pipes, increased power, etc. .P. The main difference between such pumps and waste water pumps (see above) is the impossibility of working with high-viscosity liquids.
— Waste water. Waste water pumps are in many ways similar to the models for dirty water described above because they also have to deal with large particles. The main difference is the allowable size of these particles — it is 50 mm or more; in addition, the entire design of such pumps is created based on the high viscosity of the pumped liquid.
— Chemical liquids. Pumps designed to work with chemical liquids are distinguished primarily by the use of highly resistant materials in the design — usually polymers. Due to this, they can endur...e working with aggressive substances without consequences — acids, alkalis, oil products, solvents, liquefied gases, etc. In addition, other special solutions are often used in “chemical” pumps, which allow the safe pumping of flammable and explosive materials, very cold, hot, viscous liquids, etc. The main scope of such units is the industry — both chemical and oil, food, etc. Note that different models can be designed for different types of substances.
Maximum performance
The maximum volume of water that the device can pump in a certain amount of time. It is one of the key specs of any pump because characterizes the volume of water with which the device can work. At the same time, it does not always make sense to pursue maximum performance — after all, it significantly affects the dimensions and weight of the unit.
Some formulas allow you to derive optimal performance values for different situations. So, if the pump is designed to supply water to water intake points, its minimum required performance should not be lower than the highest total flow rate; if desired, a margin of 20-30% can be added to this value. And for sewer models (see "Suitable for"), everything will depend on the volume of wastewater. More detailed recommendations for choosing a pump depending on performance can be found in special sources.
Maximum head
The maximum head generated by the pump. This parameter is most often indicated in meters, by the height of the water column that the unit can create — in other words, by the height to which it can supply water. You can estimate the pressure created by the pump using a simple formula: every 10 m of head corresponds to a pressure of 1 bar.
It is worth choosing a pump according to this parameter, taking into account the height to which it should supply water, as well as adjusting for losses and the need for pressure in the water supply. To do this, it is necessary to determine the difference in height between the water level and the highest point of water intake, add another 10 to 30 m to this figure (depending on the pressure that needs to be obtained in the water supply), and multiply the result by 1.1 — this will be the minimum pressure required.
Max. pressure
The highest pressure that the pump is capable of creating during operation. This parameter is directly related to the maximum head (see above); however, it is less obvious, and therefore, it is indicated rarely.
Maximum particle size
The largest particle size that the pump can handle without problems. This size is the main indicator that determines the purpose of the device (see above); and in general, the larger it is, the more reliable the device, the lower the risk of damage if a foreign object enters the suction line. If the risk of the appearance of too large mechanical impurities is still high, additional protection can be provided with filters or grids at the inlet. However, such a measure should be considered only as a last resort, because from constant exposure to solid particles, the grids become clogged and deformed, which can lead to both clogging of the line and filter breakthrough.
Outlet size
The thread size for connecting a hose or pipe to the pump outlet. If there is a branch pipe with an external thread in the design, the size is indicated for it; if not, for the internal thread of the inlet.
Anyway, the dimensions of the pump outlet and the mounts on the hose/pipeline connected to it must match — otherwise, you will have to look for adapters. This size is specified in inches and fractions of an inch.
This parameter is relevant primarily for surface models.
Inlet hole size
The size of the thread designed to connect the pump to the suction line. This parameter is completely similar to the size of the outlet (see above) — in particular, it can be specified both for the nozzle and for the inlet of the pump.
Maximum power
Rated power of the pump motor. The more powerful the engine, the higher the performance of the unit, usually, the greater the pressure, suction height, etc. Of course, these parameters largely depend on other features (primarily the pump type, see above); but models similar in design can be compared in terms of power.
Note that high power, usually, increases the size, weight and cost of the pump, and also implies high costs of electricity or fuel (see "Power source"). Therefore, it is worth choosing a pump according to this parameter taking into account the specific situation; more detailed recommendations can be found in special sources.
Power source
Type of energy source used by the pump during operation.
— Electric. In this case, we mean pumps powered by the mains (as opposed to the battery models described below). It is the most popular option today among units of all purposes and price categories (except water pumps with engines, which, by definition, are equipped with internal combustion engines). Electric motors are suitable for household pumps of almost any power, while they are simple, inexpensive (including in operation), operate relatively quietly, do not emit exhaust gases and do not require complex maintenance, unlike petrol and diesel ones. The disadvantages of this option include perhaps the need for external power, but this moment is not so often critical.
— Battery. Electric pumps powered by their battery. Such a power source allows you to do without connecting to an outlet, but it is poorly suited for more or less powerful units. In addition, battery life is inevitably limited, and when the charge is depleted, it is necessary to replenish the energy supply from an external source of electricity, and this takes time (although interruptions in operation can be minimized by using spare batteries). As a result, battery power is used relatively rarely — in separate submersible pumps for drainage (garden) purposes.
— Petrol. Pumps powered by internal combustion engines — including petrol ones. Such pumps combine high power and performance; they can be used even "in complete i...solation from civilization." The disadvantages of such units are high cost, bulkiness, difficulty in maintenance, significant noise level and exhaust gases arising during operation. Specifically, petrol engines are the most popular among modern water pumps with engines: they are cheaper than diesel ones, and they are also easier to maintain. The reverse side of these advantages is somewhat less suitability for long-term work, as well as the high price of fuel.
— Diesel. Another type of internal combustion engine used in water pumps with engine. Diesel units are more reliable than petrol ones, and besides, they are better suited for long-term continuous work: a diesel engine can withstand such loads more easily, and fuel for it is cheaper than petrol. The downside of these advantages is the rather high cost and complexity of the engines themselves. Therefore, diesel motor pumps nowadays are not as widespread as petrol ones.
— Gas. A very rare option used in motor pumps is internal combustion engines running on natural gas or other similar fuels. Gas is often more profitable than petrol, even though such engines themselves are not much more complicated and more expensive than petrol (and, usually, simpler and cheaper than diesel). On the other hand, the fuel itself requires particularly careful handling, and it is somewhat more difficult to obtain than petrol or diesel fuel. That is why this type of engine has not received distribution.
