Slurry pumps

Slurry pumps

All liquids that are mixed with some solids and impurities are commonly defined as slurry. Usually, along with the definition of slurry, there are also other definitions, such as the type of slurry composition, the size of the particles and the type of particles present in it, the characteristics of the slurry, the amount and volume of the particles, the type of liquid, and so on.

Slurry pumps are used to pump these types of liquids. The structure of the slurry pumps is very simple, and its design does not have the complexity and characteristics used in some other types of equipment.

The type and composition of slurry liquids and its characteristics in choosing this type of pump is important but it only identifies the strength and type of pump structure. Generally speaking, slurry pumps are of good use and are of high quality, having a high self-confidence in the mechanical design of these types of pumps, to make them a more reliable option.

The slurry pumps used today for slurry pumping are produced in various designs and models. The most common and most known used pumps are centrifugal pumps, however, positive displacement pumps or some other types of pumps, such as Venturi edtors, are also used to pump slurry.

Slurry pumps are often able to pump liquids that many other pumps cannot do, due to the fact that these types of pumps are a strong and resistant centrifugal pump designed and constructed for heavy duty operations. Centrifugal slurry pumps are designed to use centrifugal force, which means that all types of centrifugal pumps use a rotary propeller to transfer fluid. This propeller transmits energy to the liquid and causes fluid to pumping.

What is a components of slurry pump?

IMPELLERS

CASINGS

As noted above, the slurry fluid is composed of a variety of particles and contaminants, and it is proportional to the structure of these liquids, in which the components of the slurry pump are also published and constructed. Accordingly, in order to find and select the best slurry pump, the type and concentration of solids in the slurry should be considered first.

Therefore, the most important factor in slurry classification is the concentration of their solids. In general, slurries that contain 5% of solids are commonly referred to as commercial slurries, which are generally pumped by the category of slurry pumps known as Commercial pumps, the general slurry refers to a slurry that contains about 20% of the solids in weight It is usually suitable for pumping many types of slurry, and this is why they calls general slurry pump.

Slurry pumps that contain about 40 percent of the solids in their weight should be used for heavy slurry pumps. But if some slurry liquids contain more than 40% and up to 70% of solids in weight, then they should use slurry pumps for minerals, sand, which are known as slurry mineral pumping.

Of course, this is not the only factor in the classification of slurry pumps, and for the purpose of classifying these pumps, the peripheral speed of the impeller is also very important. In the design of the slurry pumps, the peripheral of the impeller is based on the type of slurry and the risk of wear, since it not only needs to be able to easily perform the work of liquid pumping, but also against wear and tear and higher wear resistance, The longer the lifetime, because solids in the liquid can cause the wear and tear of the pump.

Undoubtedly, the best methods for classifying slurry pumps can be categorized by these pumps based on the solids used in applications of these types of pumps. Slurry pumps are commonly used to pump mud, clay, sand, silt, and other types of slurries that are mixed with solids of up to 2 mm in thickness.

In this category, the measurement range is mainly: Mud/clay pumps suitable for pumping mixtures with solids of less than 2 microns. Slurry commercial pumps are usually used for pumping liquids mixed with solids between 2 and 50 microns, general slurry pumps are used for pumping liquids mixed with solids between 50 and 100 microns, heavy pumps for slurry also for pumping liquids mixed with solids between 100 to 500 microns. Finally, heavy duty minerals are used to transfer and pump liquids with solids between 500 and 2000 microns.

Of course, other types of pumps may also be taken into account in this classification. For example, Sand and gravel pumps usually used for pumping sand containing fluids between 2 and 8 mm. Gravel slurry pumps are also commonly used for pouring slurry mixtures with solid materials up to 50 mm. Dredge pumps are also a variety of heavy pumps suitable for pumping slurry mixtures with solids above 50 mm.

Types of slurry pumps

According to the above, it is possible to use a variety of slurry pumps for their type of use and the liquids to be pumped as follows:

• Slurry Pumps
• Gravel pumps
• Dredge pumps
• Sump pumps
• Froth pumps
• Carbon Transfer pumps
• Submersible pumps

The four main methods used to design slurry pumps are generally:

• Slurry pumps with horizontal and vertical reservoirs and dry-installed
• Pumps with a vertical reservoir designed for semi-dry installation
• Pumps that are designed and constructed with a tank for dry installation
• Pumps designed and constructed for wet areas and referred to as floating or Submersible pumps.

Classification of slurry pumps according to their resistance to abrasion and wear resistance
slurry pumps require different abrasion resistance due to their type of use. Accordingly, the slurry pumps are designed and manufactured in the following ways:

• Pumps that have very high abrasion resistance under very abrasive conditions
• Pumps that have good resistance to abrasive conditions
• Pumps which do not have high resistance to abrasive conditions.

CONCEPTS OF MATERIAL SELECTION

According to the exact formulas, slurry pumps are considered and built according to the amount of solids present in the liquid and the amount of resistance required for these solids due to the erosion conditions that they create. Accordingly, in order to fully understand the criteria required to produce a specific slurry pump for precise use, it is necessary to consider different parameters.
What to keep in mind is that just some limiting factors should be taken into account when selecting slurry pumps for different applications.

The restrictions that should be considered for selecting the slurry pump
1-  Type of pump depending on the type of liquid
2-  The speed required for pumping
3-  Options in different models produced

 

Selection of wear material

• Metal

According to many experts and according to the existing records, the use of metal as a whole for designing slurry pumps is a more reliable option than rubber because it has a higher tolerance and is more resistant to erosion and abrasive conditions.

But the best types of metals used to make a slurry pump are:

– High iron chrome:
This type of iron has a very high resistance and nominal stiffness of 650 BHN.
The pH value of this type of metal can be as high as 3.5, which is the standard value for making all kinds of pumps.

– Manganese steel
Manganese steel, in particular, for the construction of slurry pumps, is a very good option to be considered as a nominal 350 BHN.

• Elastomers

One of the most widely used rubbers for slurry pumps is natural rubber, but nonetheless, other types of rubbers, mainly made from synthetic rubber families, are also used to produce slurry pumps. The important thing is that the higher the rubber resistance, the more expensive the pump should be paid.

However, the crucial factor for selecting rubber is the amount of solids in the slurry that create different abrasives, but mainly tires of between 5 and 8 mm are best suited for use in the production of slurry pumps, because if they do not follow this The thickness of the solid rubber in the liquid, especially if thick and hard, can easily damage the rubber and then pump it.

Generally, a variety of types of rubbers are used to produce slurry pumps, most commonly used and most applicable are:

• Types of elastomer family rubbers
• Natural rubber
• Many of thesynthetic rubber and polyurethane rubber

Pumps today are one of the main industrial elements used in various industries, and even houses, which perform various services such as cooling, lubrication, flow transmission for processing and delivery of power in hydraulic systems and other types of applications.

 The use of the pump has caused many industrial problems and challenges to be easily addressed. Today, even in industrial, administrative, commercial or urban buildings and residential complexes, there are many uses of pumps for daily water pumping operations or hot or cold water spinning for a heating or cooling system.

Even in the production sectors, the pumps provide about 27 percent of the electricity needed for production operations. Pumps are the main components of air conditioning, heating, cooling or water supply systems for the transfer of heat in the commercial sector.

Pumps are also used to transfer water and liquid and sewage treatment or as drainage in municipalities. In residential and office complexes, pumps as well as high pressure water supply suppliers are widely used.

Due to the fact that today pumps are used for different purposes and different needs are met by using pumps in different industrial and non-industrial sectors, the range and variety of pumps are widespread today. In fact, today’s half-horsepower pumps up to a several thousand horsepower are produced.

ump manufacturers Depending on the market demand, today, various types of pumps are produced and marketed in the market not only in terms of dimensions but also in terms of volume and type of work. This is done to classify the pumps by adding energy to a fluids.

Based on the types of pumps that are produced, they can be defined in the following categories:

• Positive displacement pumps that directly transfer pressure to the liquid
• Centrifugal pumps, also known as rotodynamic pumps. These pumps are used to increase the speed of fluids and convert the energy to the pressure.

Of course, it should be kept in mind that each of these types of pumps themselves are under other categories. The types of lobes, sliding vane, pistons and screws are components of the positive displacement pump series.

Underneath the categories of centrifuge pumps are also mixed or blended types, axial or propeller and radial.

Several factors have to be checked to find out which of the pumps are suitable for a specific application. However, many pumps are designed and manufactured in such a way that they can cover several different users.

The important thing for pumps is that the pump has a high reliability because there is a lot of sensitivity to this topic and is often criticized. Particular consideration should be given to the fact that the cooling system of the pump is very worrisome because it can cause overheating of the various equipment, which could lead to the destruction of various devices and equipment.

It is also important to use the pump in lubrication systems in order to prevent damage to many equipment. The failure or inappropriate use of pumps in petrochemical plants and power plants reduces their productivity in these industries, which is often a tangible reduction in productivity. In fact, the use of the pump is seen in many modern day operations, and it can be said that the pump has become an integral part of the lives of today’s people.

Subsequently, the use of pumps in different industries and applications requires a precise and regular program as a maintenance system. In addition, the operation of the pumps in order to maintain the optimal efficiency of the pumps and to ensure the satisfaction of the different requirements of different systems in different conditions is one of the important principles of maintaining systems for the pumps.

In many industries and applications, engineers try to re-examine and overlook the overhead of the pumps in order to ensure that the pump is properly selected for the specific system requirements, because the pump overhead should be large and strong enough. However, the larger the pumps are, the need for repairs and maintenance and costs more.

The inappropriate selection of the pump is not only involves selecting a pump with a lower capacity and size for the system, and sometimes selecting a pump larger than the desired capacity will increase the cost of system maintenance considerably.

 In addition, along with the large cost of large pumps for the system of planning and maintenance should not be at risk of more pumps with greater volume, the smaller the pump size and volume, the cost of repairs and maintenance and risks There are fewer sideways for the system, but nevertheless, the pump must be selected in appropriate dimensions and sizes to meet the system’s requirements.

It should also be noted that large pumps generate a lot more energy; this energy, if applied in systems with lower capacity and lower power, causes the components of the system to loosen and can lead to the consequences of a breakdown or failure valves , Plumbing voltage or excessive noise in the plant’s plant system or any other location.

What is the components of typical pumping system?

As the main components of a pumping system, the pumps themselves can be found alongside the main engines or prime movers, plumbing or piping, valves and end equipment, such as heat exchangers, tanks, thermal equipment and hydraulic equipment. This pumping system can be defined as the simplest pumping system for ordinary purposes. In Figure 1, a typical pumping system and its components are described.

Pumps
we have already explained that the pumps are divided into two main categories: positive displacement pumps and centrifugal pumps. But in these two main categories of pumps there are a wide variety of different types of pumps in different sizes and capacity for different purposes. The basis for the division of the pumps into these two general categories can be defined generally as the type of energy transfer to the liquid flow.

Centrifugal pumps and positive displacement pumps are different in operation and type of pumping. Positive displacement pump, by pressurize fluid with a collapsing volume action often make the compression volume equal to the displacement of the system with each stroke or rotation of shaft, but the centrifugal pump performs fluid transfer with the help of a rotary propeller, and in fact with The conversion of kinetic energy to electronic energy does this.

 The kinetic or kinematic energy increases, when the flow in the pump diffuser section decreases.

Both positive displacement pumps and centrifuges pumps can be used for different purposes and can cover a wide range of needs and applications, although the use of centrifugal pumps is more common and more often Attention, perhaps the main reason for this issue is simpler and more secure for these types of pumps. Meanwhile, centrifuges pumps have a longer life center and easier and cheaper maintenance and repair conditions.

Comparison between positive displacement pumps and centrifugal pumps

Generally speaking, positive displacement pumps from centrifuge pumps need less repair and less damage, as they are less exposed to wear and require less replacement. Like all types of pumps, the centrifugal pumps also have a mechanical welded structure and a certain mechanical package, but nevertheless, these pumps have longer cycles and longer lifetimes and lower maintenance costs.

Another advantage of centrifuge pumps is that they can be used in a variety of work programs and in a wide range of applications, and perhaps one can safely say that there is not much restriction. It is safer to use these types of pumps, because even if they are chosen and used improperly, they will be less likely to damage the equipment and the structure of the plant, but again, this should not make the pumps inappropriately selected and care should be taken.

Another feature of centrifuge pumps is the change in flow and pressure. For example, if a centrifuge pump is used against in high-pressure systems, the flow rate of these pumps will be lower than that of those pumps used in low pressure systems.

However, centrifuge pumps are characterized by high pressure and high flow rate relationship, in which flow is considered as a function of pump head or pressure. Understanding this kind of relationship in centrifugal pumps is very important aid in choosing a suitable pump to make the system more efficient.

In positive displacement pumps, we see a constant volume of fluid displacement versus centrifugal pumps. This feature makes these pumps have a constant and alternating current at a constant and constant speed. Generally, the pressure of the positive displacement pumps is selected according to the current flow determined for the system. The use of positive displacement pumps in residential complexes and other special applications is due to the characteristics and many advantages of these types of pumps.

Applications of Positive displacement pumps

 Considering the important characteristics that have positive displacement pumps, many applications of these pumps are most commonly used:

• Used for pumping heavy liquids with high viscosity
• Use in systems that require high pressures along with low performance.
• Use in systems that need self-priming pumps.
• Use in systems that do not require highshear force flow
• Use in systems where accurate measurements and flow control are of great importance.
• Use in systems where pump efficiency has a higher priority.

The use of protective systems and special safety measures in all systems and installations that use positive displacement pumps should not be forgotten as a principle. Positive displacement pumps have very high power and can potentially transmit high amounts of liquids at high pressure in the system, which can put extra pressure on all the infrastructure and components of a system.

In order to understand most of this, it is better to consider a completely closed system with lower pump valves, in which case it is said that the deadheaded conditions have been created, this condition until one of the valves Emergency action, will continue. In this case, if the emergency valve is not considered, the pressure will be applied, or the pump will be damaged, or it will find its way out by tapping the pipelines or connections.

Therefore, in these conditions, valves should be used as one-way valves or safety valves to reduce potential and system safety, but not only these safety valves should be relied on, and emergency evacuation valves should also be seen in the facility’s path.

In addition, the use of flushing valves or drain valves using a sewage system can reduce the pressure on the lines of the facility, although it is not responsive in all systems. In fact, the system must be accurately calibrated and designed and, if this is done incorrectly, the pressure applied will enter the damage before it leaves the drainage valve.