How to choose a submersible electric pump for industry

The industrial submersible electric pump is a very useful system for a variety of industrial sectors. This hydraulic mechanism offers many possibilities of use when it is necessary to move large quantities of water. Just think of the essential contribution of these pumps in the construction industry and during the design of an industrial plant. In both cases, the movement and withdrawal of water is indispensable.

In addition, its electrical operation is useful for counteracting gravity and thus enabling faster movement of liquids from point A to point B, even if there are differences in level with a more or less steep slope. But how do we choose an industrial submersible electric pump? First of all, we need to be clear about the existing types and understand the requirements the pump has to respond to. This article describes the most important things to know.

 

Electric pump for industrial applications

There are many different industrial applications that require the presence if a submersible electric pump. From agriculture for irrigating fields, to designing a septic tank, to pumping sewage. Before choosing a submersible electric pump, there are three fundamental aspects to consider in order to find the solution that is right for you.

  1. Type of use. The first thing to do is to have a clear idea of the performance features and type of use required of the hydraulic system.
  2. Type of liquid. You need to pay particular attention to the liquid that has to be moved through the pump, which is not always water, especially in industrial settings.
  3. Quantity of water. You need to assess how much water you actually need to move and opt for models that can satisfy your needs.

In addition, it is important to define what the essential characteristics of a submersible pump are, namely:

  • Maximum immersion depth
  • Automatic or manual operation
  • Safety system in the event of water shortage
  • Diameter of the outlet necessary to pump the liquid at the performance level required by the system
  • Weight of the product
  • Dimensions of the electric pump
  • Length of the power cable and related thickness, as well as the IP degree of protection.
  • Resistance to the level of water acidity and construction material
  • Operating voltage
  • Size of the solid waste that it can break down
  • Maximum temperature of the liquid
  • Solar adaptability

 

Purchasing an electric pump for industrial use

Moving large quantities of liquids from one point to another is a need in various industrial sectors, and the solution is a submersible electric pump. Precisely for this reason, there are a number of different models of industrial submersible electric pumps, the choice of which is mainly dictated by the type of application it will be used for.

Among the essential requirements for making the best choice, in addition to those already specified, you need to consider:

  • the power that determines the quantity (Q) to be pumped within a given time
  • the flow rate (litres per minute or cubic metres per hour)
  • the column height (H) to which the liquid can be conveyed
  • the head (metres).

So purchasing an electric pump for industrial use is anything but simple. The first step to take in order to make the right choice is to rely on experts like those you can find at Pompe Zanni.

Electric hydraulic pumps: what they are and the advantages they offer

Electric hydraulic pumps are special mechanical devices that can move liquid vertically and horizontally depending on the different requirements. Hydraulic pumps differ for the motive force that drives them, and these include pumps that are electrically operated. So let’s look at the features, advantages and main types of these devices, which are extremely useful in a number of different sectors.

What are electric hydraulic pumps?

The main characteristics of electric hydraulic pumps that should always be taken into account are the flow rate and head. Depending on the type of use and the specific requirements of the area in which the device is used, we can choose the pump that meets our needs.

Let’s take a closer look at what is meant by flow rate and head.

  • Flow rate: is the quantity of water, or liquid, moved by a pump in a unit of time. It therefore expresses the ratio between volume and unit of time, generating a litre/minute value.
  • Head: is the maximum height that a pump can move fluid against gravity and is indicated in metres. This characteristic is fundamental in order to know if the pump is right for our application.

Specifically, the operation is generated by a motor which is this case is electric.

 

The advantages of electric hydraulic pumps

These fluid moving devices are helpful in a number of different areas. Consider the need in agriculture to move large quantities of water for irrigating fields, but there are other applications. Electric hydraulic pumps are also indispensable in the oil, chemical, and metal industries.

This is obviously because they offer a number of advantages:

  • recovering water in a well and bringing it to the surface
  • recirculation of liquid to specific pipes
  • cleaning water inside a swimming pool
  • moving water form a cistern to individual houses
  • desalination of water by means of hydraulic pressure.

 

Main types

There are different types of electric hydraulic pumps depending on the type of use. Below we list the most important features that define the main models and the individual uses.

  • Centrifugal pumps: are used to apply more pressure to the water and to convey water to or from a tank, to supply an autoclave, for pressure washing systems, for filling tanks and swimming pools, for irrigation, as well as all other needs related to simple level movement or pressurisation.
  • Submersible pumps: are used for extracting and pumping from the subsoil and at the same time providing pressure at the outlet, in order to supply a column of water in a vertical direction. They are equipped with a watertight motor that allows them to be installed submerged in the liquid, even at considerable depths.
  • Self-priming pumps: combine the function of centrifugal pumps and submersible pumps. They are used for extracting and pumping liquids from the subsoil and at the same time to give pressure at the outlet. They are mainly installed near a well.
  • Immersible pumps: are used for extracting and pumping liquid from tanks or swimming pools. One of the most common uses is for emptying flooded garages or cellars or for septic tanks. They are equipped with watertight motors in order to be immersed and are able to push sludge or sewage in a vertical direction.

Causes and prevention of cavitation in a pump

Cavitation in a pump is a physical phenomenon that affects all hydraulic systems and machines in general. This particular effect manifests with the formation of small bubbles, whose immediate collapse causes micro jets at very high pressure that can cause even serious damage.

One of the most common mechanical failures in a centrifugal pump is cavitation. Like all mechanical equipment that has been in service for several years, also pumps can be subject to damage to their components due to wear and tear.

 

Cavitation in a pump: how it happens

This phenomenon originates in nucleation, i.e. the origin of very small cavities that can constitute nuclei for the growth of macroscopic bubbles that will collapse shortly afterward. More precisely, this process can happen in two different ways:

  • Homogeneous: when the thermal motions inside the liquid create microscopic voids that can turn into bubbles.
  • Heterogeneous: when the presence of microparticles is detected which are dispersed in the primary fluid or caused by the roughness of the walls of the duct containing the fluid.

The tendency toward cavitation in a pump can be correlated to the presence of high head, significant hydraulic pressure losses in the suction line, considerable difference in level between the pump and suction tank, and high vapour pressure of the sucked liquid.

 

Cavitation in a pump: causes and consequences

The causes of cavitation in a pump can be many and varied. From improper use by the operator, to the quality of the products of centrifugal pumps, and so on. Pompe Zanni products easily pass all the inspection procedures, making the pumps less prone to this type of problem, precisely because they are built using the best materials available.

In the working state, the operating environment of the centrifugal pump and the influence of operating factors represent the largest part of the relationship between cavitation and the centrifugal pump.

The collapse and implosion phase releases an amount of energy that can cause major damage to the system. The main harmful consequences can be summarised as follows:

  • worsening of pump performance due to the turbulence caused by cavitation. In terms of efficiency, it is estimated that a decrease of at least 3% is due to this phenomenon.
  • Excessive vibration of the pump, which causes noise.
  • Deterioration of the pump’s internal components, due to the collapse of the bubble near the wall of a component. In this case a liquid microjet (impinging jet) is generated, which erodes the solid surface and forms what are called “erosive pits”. The area where this phenomenon occurs most frequently is at the outlet of the impeller, because in this section there is a temporary depressurisation of the liquid, followed by a subsequent increase in pressure.

 

Cavitation of a pump: prevention

To prevent cavitation, the pressure of the liquid at all points must be below the saturation pressure. Some useful tips are:

  • Use pumps in series or a multi-stage pump to reduce the head of the single pump (or stage)
  • Increase the diameter of the pipe and/or decrease the length of the suction path
  • Use a submersible pump or otherwise place the pump at the lowest possible level
  • Reduce the temperature of the liquid (lowers the saturation pressure)
  • Decrease the pressure drops in the pump
  • Reduce the flow rate in the pump
  • Decrease the impeller speed
  • Increase the pressure at the pump inlet

 

 

Electric hydraulic pumps: types and advantages for every use

Electric hydraulic pumps have the specific function of moving the flow of water through a mechanism powered by electricity. These systems can be the solution for recovering liquids in different sectors and situations, from industrial to agricultural use, and for domestic use for smaller devices.

In any case, the main element of electric hydraulic pumps is the motor, which enables the pump to perform its task of recovering the flow water. The energy produced by the electric motor enables the movement of water or a specific liquid from one point to another. But let’s take a closer look at what electric hydraulic pumps are and which types are present on the market.

 

What are electric hydraulic pumps?

Electric hydraulic pumps are systems that have a specific structure mainly divided into 3 parts:

  • suction, i.e. the inlet of the liquid, positioned in line with the central axis of the electric pump;
  • the electric motor that moves the impellers, which in turn push the liquids to the centre of the pump outwards;
  • the outlet, where via the electric impulse the energy is transformed into pressure, or head, which pushes out the recovered liquid.

All Pompe Zanni electric hydraulic pumps guarantee an optimal mechanical seal of this process, thanks to which the recovered water is prevented from passing through the motor and consequently interrupting its operation.

The maximum performance of a hydraulic pump is achieved when the flow rate is zero. In this way, having no displacement of liquids, all the energy will be transformed into hydrostatic pressure.

On the other hand, when the flow rate is higher, the water pressure decreases. This is because the energy will be used to move the water towards the outlet.

 

Advantages of electric pumps

Choosing an electric pump means being able to rely on a fundamental tool for different applications. Electric hydraulic pumps can provide a number of advantages for:

  • recovering water in a well towards the surface;
  • circulating the water and moving it towards specific piping systems such as radiators;
  • cleaning the water of a swimming pool by filtering it;
  • moving the water collected in a cistern towards different houses;
  • desalinating water by exploiting the hydraulic pressure.

 

The main types of pumps

There are various types of these systems. Very briefly, they can be classified according to:

  • the direction of the flow that passes through it, distinguished as: centrifugal, when it is necessary to provide high head with low flow rates, and axial, when it is necessary to provide low head at high flow rates.
  • The axis, which can be horizontal, vertical or inclined.
  • The pump casing, which can be on the surface, submerged, or coaxial, depending on the position of the liquid to be moved.
  • The number of impellers, distinguished as single-stage pumps, i.e. with a single impeller, or multi-stage pumps.
  • The material, which can be metallic or thermoplastic.

In addition to these particular characteristics, there are other criteria for distinguishing different types of pumps. It is very important to differentiate monoblock pumps and magnetic drive pumps.

  • Monoblock pumps: have the casing and impeller machined from the billet in order to make the most of the mechanical characteristics of the thermoplastic material. These pumps are optimal because they do not have the typical defects of moulding such as voids, burns or deformations.
  • Magnetic drive pumps: in which the power of the motor is transmitted to the pump impeller without contact and by means of a magnetic coupling, making any liquid leakage impossible. These pumps are the ideal solution when dealing with corrosive liquids.

 

Choosing the right irrigation pump

Irrigation pumps can be used to do various jobs in agriculture.

They can be used to draw up water from a well or to recover rainwater stored inside a tank.

Choosing the right pump depends on several factors. The first element to consider is the sizing of the pump.

Calculating the right irrigation pump

The first step in defining the specifications of the ideal pump is the sizing.

When we talk about pump sizing, we are referring to the hydraulic performance it has to deliver so that the tool distributes the predetermined amount of water as needed.

The two fundamental aspects involved in this are its flow rate and head:

  • the flow rate indicates the amount of water the pump can shift in a given period of time;
  • the head indicates the difference in level that the water can overcome thanks to the pump’s action, i.e. the difference in height between the point of intake and the point of delivery.

“Drip” irrigation systems are among the systems where irrigation pumps are used most frequently.

Drip irrigation pumps and agriculture

Drip irrigation is also known as micro-irrigation, i.e. a slow, drip-by-drip irrigation system enabling plants to be watered uniformly while avoiding wastage of water.

Surface pumps and submersible electric pumps are used in this type of system in order to draw water up from wells and tanks.

Pompe Zanni has a wide range of vertical-axis centrifugal pumps, powered by tractors, diesel engines or electric motors, and can draw up water from depths of up to 300 metres.

What do you need for your agricultural jobs? We are confident we have the right solution for you.

Come and have a look at our products and get in touch for further details and a quotation.

Submersible pumps: application and how they work

Submersible pumps are versatile and effective devices used in a variety of applications, including industry, civil engineering and agriculture.

Submersible well pumps and fields of application

Among their many applications, submersible pumps are used in fire-fighting systems and pumping stations as well as to draw primary water from wells.

In industry they can be used to carry purified water, while in agriculture they can support irrigation systems and other water systems used in cultivation.

Submersible pumps: how they work

Submersible pumps differ from surface-mounted pumps in that they operate while submerged in the water that they are required to pump. The width and depth of the well are, therefore, important details to consider in choosing one over the other.

The level probes, the main feature in our pumps, are remotely controlled via a control panel on the surface. This component has an important monitoring and protection function.

The most suitable option should be chosen depending on the flow rate, head and motor power that your specific use requires.

At Zanni we manufacture two different types of submersible pumps:

Both versions have been designed down to the smallest detail. Every material has been carefully selected and every piece undergoes stringent quality controls.

At Zanni we produce a comprehensive range of pumps for any need and walk the customer through the steps to select the most suitable product.

What’s the best solution for your needs? Contact us for our expert advice on the best submersible pump and to discover our models.

Tips for choosing a centrifugal pump

When choosing a centrifugal pump you need to take several aspects into account, whether technical or not. Context of use and other variables can, in fact, affect the choice of the most appropriate model.

Let’s take a deeper look at these factors.

Choosing a centrifugal pump: What you need to know

First things first: if you want to avoid wear and corrosion problems, you have to consider the kind of liquid you want to move. Find out what the liquid’s chemical characteristics are, including viscosity and presence of any solid particles, so you have no hesitations about the ideal pump you need and its operation.

Depending on the specific application, you will also have to consider pump sizing, in other words, the amount of liquid in the use cycle. This is an important factor in order to optimise costs.

Assessing the pump and system’s technical characteristics

Delving deeper, a centrifugal pump is made up of fixed parts and moving gears that generate a circular motion at a certain speed. The first characteristics to look at are its flow rate and head.

Flow rate is the volume of water that moves inside the pump expressed in seconds or minutes; head is how high (maximum) the pump has to lift the liquid from the point of intake.

The system, on the other hand, is mainly made up of the pump drive motor, suction and discharge pipes, filters, valves, and the pump’s priming and drainage systems.

Pump types

From vertical pumps to horizontal pumps, these tools find application across many sectors and businesses, from industry to agriculture, through to private uses.

Let’s start with steel submersible pumps, which are widely used in industry and for irrigation. These pumps are easy to install and feature submersible motors and built-in check valve. They come in two versions:

  • radial flow, for limited flow rates and high pressures;
  • semi-axial flow, for high flow rates and medium pressures.

Cast iron submersible pumps are similar to these and have a great power level. They are also driven by a submersible motor and equally versatile across fields of application in terms of liquid supply.

Split case pumps are another interesting solution. With their separate chamber, they are innovative from both a technical and maintenance standpoint. In fact, since the pump casing is axially split, the rotor can be worked on without meddling with the motor or pipes.

Do you want our advice about which centrifugal pump to choose? Contact us now! We’ll be happy to help.

 

Difference between centrifugal and positive displacement pumps

Centrifugal and positive displacement pumps are tools that play a key role in today’s industry. Their function lies in the ability to transfer fluid from one point to another, be the level high or low. However, they differ in the way they work and the type of fluid moved. 

Pump classification

centrifugal pump

A macro breakdown immediately comes to mind when we think of pump classification, one that helps us to better understand the difference between centrifugal and positive displacement pumps. This breakdown regards, first of all, the fluid pumping method:

  • Hydraulic pumps
  • Positive-displacement pumps

In the first case, the pumping action is achieved by the fluid’s dynamics whereas in the second, it is achieved by the variation in volume. Centrifugal pumps fall in the first case.

Centrifugal pumps and positive displacement pumps in detail 

Centrifugal pumps use an impeller to activate a centrifugal effect that moves the water (or other liquid) and converts mechanical energy into kinetic energy; the latter thus exerts strong pressure on the fluid, displacing it.

In terms of the level of the intake, centrifugal pumps clearly have to pump the liquid from a lower to a higher point. Underlining this aspect is not trivial because this scenario represents most cases. In fact, a pump is rarely used to transfer liquids from a higher to a lower point.  

What are the advantages of a centrifugal pump?

Centrifugal pumps are the most commonly used of hydraulic pumps, both in industry and by private individuals, but also in farming (such as the centrifugal pumps for irrigation systems).  

 

Displacement pumps generate energy periodically. As already mentioned, they use the variation in volume to produce suction or thrust of the water. These include rotary pumps and reciprocating pumps and are used for higher-density fluids.

 

Because of the way these pumps function, pump manufacturers, businesses and institutions have come to understand the significance of pumps for solving environmental issues. Are you aware of their use in this area? Contact us to learn more. 


 

 

 

How does a centrifugal pump work?

Pumping systems are becoming increasingly essential in this day and age. Knowing how a centrifugal pump works can therefore solve many issues of an environmental nature, not to mention problems associated with a variety of different work environments.

Centrifugal Pumps Operational characteristics

Pumps are mechanical instruments that increase a liquid’s energy by means of pressure; the design of a centrifugal pump includes stationary components and a mobile gearwheel, the impeller, which rotates at a specific speed.

 

centrifugal pump

Technically speaking, a centrifugal pump’s impeller is a wheel equipped with vanes; it can be constructed in a variety of ways, depending on the desired function.

 

Prior to fully examining the components that contribute to its operation, we must consider the preliminary research and design phase, which has a crucial impact on the system’s efficiency. It is during this phase that the sizing of the centrifugal pump takes on particular importance.

 

Centrifugal pump sizing 

 

Proper sizing of the centrifugal pump ensures the correct amount of liquid per normal use cycle; it is also important because it is needed to estimate project costs and operating costs. By preventing oversizing, this step reduces costs to a minimum.

Centrifugal pump flow rate, head and power

 

One of the primary aspects to consider is the flow rate of the centrifugal pump, or, in other words, the volume of the water that passes through it in a given amount of time, expressed in seconds or minutes; this is especially pertinent with regard to the agricultural sector, and specifically when dealing with centrifugal pumps for irrigation.

 

Head, which is the pressure jump produced by the pump, is closely linked to the centrifugal pump’s flow rate. Head is a measurement that decreases as flow rate increases; it is expressed in metres, and indicates the peak height to which the pump can raise the water with respect to the source point.

 

Lastly, the power is the energy the system requires in order to continue raising the water’s flow rate and, as such, is directly responsible for the centrifugal pump’s hydraulic efficiency.