Category Archives: industry

Top Tips to Choose the Best Connectors

From smart phones to sophisticated machineries that manufacture them, you can find an electrical connector in many forms. If you are an electrical industrialist or purchase engineer, it is essential to have some key factors in mind before making your final choice.

Here are a few essential aspects to check while choosing a connector:


Power of the connector is a determining factor. The market offers a wide range of connectors with different power-ratings. Identify your requirement and choose the one that meets the purpose.

A low power variant may not give you the expected efficiency and on the other hand, a high power connector can even damage the entire system.


The density of a connector is yet another influential factor in the present day. The higher the connector density, the more compact your machine design will be. This is especially important in case of complex machineries. In order to keep it solid at the same time give exceptional performances, it is essential to choose a high-density connector.

Temperature Resistance

Another important feature that adds to the quality of a connector is its capacity to withstand high temperatures. Most of these connectors are used in intricate machineries and they undergo immense heat exposure during their functioning. High-end connectors are often passed through multiple levels of testing to ensure its temperature resistance.


The transmission speeds of connectors are quite significant for their overall performance. Many of the latest connectors ensure to meet high transmission speeds. ExaMAX High Speed Backplane Connectors are one of the best you can get in the market these days.

Mating Features

The mating features of any connector play an important role in determining its performance, quality and durability. Before you choose your connector, ensure that you scout through specifications to analyze its mating features. The angle of mating, the number of mating cycles, etc. will be clearly mentioned in the specifications, which help to find the one matching your requirements. Mating cycles are especially important for connectors that are mated and unmated frequently. For a USB connector the mating cycles will be in thousands where as for a board to board connector will have a lesser mating cycle.

The Perfect Packaging for Every Product

Whether you talk of fresh food items, dry groceries, machine parts, furniture or hardware, every product needs to be well packaged. The type of packaging best suited to a product depends on a number of factors including cost of the product, perceived value, size, fragility, shelf life etc. Thus, there are a number of materials that can be used to package a product such as paper, polythene, corrugated cardboard, cartons, shrink wrap and pallets.

Why do you need Packaging?

The most obvious reason to package a product carefully, is to protect it while it moves from the factory floor to the retail shops and then to the customer’s house. However, this is not the only reason to focus on packaging. Packaging plays an important role in a customer’s decision making process. The way a product is packaged is the first interaction many customers have with the product and hence this plays an important role in creating a first impression. A well packaged product speaks of attention to detail and helps build trust in a brand name.

Packaging is also important from a marketing perspective. This is because whilst the product itself may offer limited space for branding, a carton or sleeve allows a much larger space for branding thus making the brand name more visible. When it comes to wholesale packaging, cartons are usually left plain. However, it is still possible to brand the cartons by using printed carton tape.

How to Choose the Right Packaging Material

The wrong packaging can put a customer off the product. The first step to packing a product is to select the right material. There are many factors that must be considered when picking packaging materials. These include:

Type of Product- While dry groceries need to be packed in such a way so as to be visible to customers and yet protected against natural elements; product visibility does not matter when packing hardware items or machine parts. A few other product characteristics to keep in mind are sensitivity to light and moisture, shelf life and reaction to other materials.

Cost of the Product- The cost of packaging a product should be in direct relation to the cost of the product and should not exceed it. Thus, whilst clear, polythene bags are sufficient packing for disposable plates, bone chine needs to be packed in boxes with cushion packaging.

How the products are to be shipped- To a certain extent wholesale packaging also plays a role in determining the right material for retail packaging. For example, if the products are going to be packed in a larger carton, puncture resistance is not a high priority. However, if the products are going to be stacked on a pallet, this is a factor that will need to be considered.

Common Types of Packaging

Paper Board

Paper is the cheapest and most ecofriendly way to package a product. Paper is often used in the form of boxes to package low cost items such as stationery or in the form of paper bags for fast food and other consumables.


Polythene bags are the most preferred form of packaging for products such as dry groceries and liquids. This is because it is transparent thus allowing the consumer to see the product being purchased and protects the food items from natural elements.

Rigid Plastic

Rigid plastic may be used to package both consumables and non-consumables. This is a chosen packaging material when the product needs to be visible to the consumer and yet protected against shocks and being accidentally dropped etc.

Corrugated cardboard

When it comes to large products such as furniture, it is not possible to fit the piece into a carton. Hence, such products are usually wrapped in corrugate sheets to protect them against bumping into other things or being dropped accidentally.

Factors to Be Considered While Choosing Heat Shrink Tubing

Heat shrink tubing comes in different materials. It is normally made of nylon or polyolefin and sometimes it is also made of PFTE. The ones made of PFTE are more resilient and tough whereas another variety called the Viton heat shrink tubes can withstand extreme temperatures and are impervious to a series of chemicals.

One has to choose the right type that will suit your application the best. Several factors such as environmental hazards, voltage, temperature ratings and other application needs have to be considered while making your choice of the tubing. In addition, a few other considerations that will ensure you get the right type of tubing are:

• Sleeve diameter of the tubing: The diameter in the original form should be big enough to cover any sort of irregular surface and at the same time should shrink to a final diameter that will fit snugly around the application. The shrink ratio becomes important here.

• Shrink ratio: The shrink ratio determines the final diameter of the tubing. It varies from as high as 6:1 to as low as 2:1. Tubing which have high shrinkage ratios act as weather-proof sealants for huge cable bundles. Depending upon the application requirements, the tubing has to be wisely chosen.

• Rigidity and wall thickness: Thick walled and stiff tubing is necessary for applications which require high levels of strain relief and toughness. Less rigid and thin walled tubing is good enough for other applications.

The shrink temperature is different for different materials and therefore this factor has to be kept in mind while applying the heat for shrinking. Normally, a heat gun is used while heating the tubing as that has a better control over the air flow and temperature. Sometimes, butane torches are also used.

For some applications, adhesive lined tubing is used. As the name suggests, the insides of adhesive lined tubing are coated with a thin glue layer. The glue melts when heat is applied for contracting the heat shrink tubing and this helps to generate an even and a sturdier bond between the tubing and the cable around which it is wrapped. This bond is further strengthened after the glue dries up making it almost impossible to be broken. At the same time, the tubing remains as flexible as the heat shrink tubes without the adhesive.

Heat shrink products play a significant role in maintenance and protection of electric cables. They undergo several testing procedures before they are released for use. There are several dealers and manufacturers offering these products and choosing a reputable dealer is of paramount importance.

There can be no compromise on quality as otherwise the security of your application can be affected. So, don’t go just by the price when you make your choice of the heat shrink tubing; consider the factors mentioned above and you will have the perfect heat shrink tubes that fulfil all your needs.

In some other projects, the heat shrink sleeve proves most appropriate. This is so especially in case of industrial situations where the pipes are continuously exposed to extreme heat and corrosion. The sleeve acts as a protective cover and ensures the longevity of the pipes.

Brief on Types of Gears Used in Manufacturing Plants

Some of the various types of gearboxes that find their way in different industries are the worm gearbox, helical gearbox, spiral bevel gearbox, bevel gearbox, shaft mounted and many more. Each of them comes with different features such as shock-resistant, lightweight, small volume and novel structures and each of them has a specific role to play in the application. Some of the manufacturing plants where the is needed are:

Cement: High-torque and rugged is needed in the cement industry for ensuring continuous operation, consistent load and compact installation. Some of the gear used here are Bevel Helical, Parallel Shaft and Bevel Epicyclic gearbox.

Paper & Pulp: which have high torque capacity and differing gear ratios are in demand in this industry. The that are normally used here are helical, shaft mounted and spur gearbox.

Sugar: Gear that offer noiseless and smooth functioning are required in this industry. The main gear that are used here are helical and planetary gearbox.

Steel: Heavy duty industrial equipment and machinery is needed to manufacture different kinds of steel and allied products. This has necessitated the need for powerful gears and to run the heavy machinery smoothly and efficiently. Some of the used here are worm reduction, planetary, spur and helical gearbox.

Power: Power generation, transmission, utilization and distribution require heavy electrical equipment. In order to ensure the seamless functioning of this machinery, high precision and gears are needed. Gearboxes with powerful performance and high torque capacity are available with various gearbox dealers.

The gearbox is the foundation of any machine or engine in the world. The gearbox is responsible for providing torque at great speeds and hence there is a possibility of it losing control and moving out of place. For a gearbox to function smoothly for a long time it is essential that it is purchased from a reliable manufacturer.

Greaves are one such reliable brand that can be used for a long period of time. Each kind of gear and gearbox has an important role to play in the application for which it is used. The helical gears reduce noise, pollution and offer smooth functioning. Bevel gears are very helpful in applications where changes in the shaft’s rotation are required and so on. Therefore all the components used in the manufacture of each gearbox should be of great quality. It is essential for all reliable inline helical gear dealers and other gearbox dealers to stock only top quality items so that there are no complaints from any of its customers.

Welcome to S.C. Industrial Syndicate
At S.C. Industrial Syndicate, we pride ourselves on offering our customers responsive, competent and excellent service and we offer only quality products: Crompton Greaves Electric Motors, Crompton Greaves AC Drives & Variable Speed Drives, Crompton Greaves Industrial Pumps & Fire Fighting Pumps, Premium Greaves Worm/Helical Gearboxes, Premium Stephan Geared Motors and Pembril Fluid Couplings. Our customers are the most important part of our business, and we work tirelessly to ensure their complete satisfaction.

5 Ways Dehumidifiers Can Improve Commercial Food Production

Although making food in your kitchen and making food on a commercial scale might seem much the same, the realities are that they are, in fact, almost completely different. Of course, whilst the end result of both endeavours is (hopefully) delicious food, the way those foodstuffs are produced it wildly different.

From industrial mixers to fully automated moulding and baking machines, the commercial food production industry barely resembles what you might do at home.

So, whilst you might not need a dehumidifier in your home kitchen, you certainly need one if you’re operating a commercial food production company. But why? Here’s five big reasons:

#1 – Improved production speed

If drying is part of the manufacturing process for your business, whether you’re stove drying or dry curing meat, you can waste days, weeks and even months waiting for the process to occur naturally in an uncontrolled environment.

By leaving ambient conditions in place, the natural inconsistency of air humidity will deliver an uneven and unpredictable results which can spoil or halt production. Alternatively, by introducing effective humidity control into an environment you can dramatically increase the speed of your drying procedures.

Indeed, one business was able to reduce their stove drying time from 5 days to 1.5 days, more than doubling the output of their existing stoves and delivering a more consistent end product. Increased drying times naturally lead to a higher level of output, which in turn means more profits.

#2 – Unified production rate

Winter conditions might well offer ideal humidity rates for food manufacturing, but the summer months aren’t as kind. High humidity can slow production to a crawl during the warmer months, so installing a commercial humidity control system is essential. It’ll help level out your production rates and equalise output levels.

#3 – Improved product quality

Humidity can cause a number of number of issues in quality control of food and drink manufacturing. Whether it’s causing dried fruit to clump, bread to become misshapen or plastic to bottles to become distorted in production, humidity can be a real nightmare for quality control.

It doesn’t take a genius to work out why quality control is important for your business, so don’t waste time producing inferior products.

#4 – Reduced costs

All machinery is affected by humidity, and by leaving it unchecked you’re opening the door to condensation on equipment, damp electrical panels and more. By operating a humidity controlled area, you can reduce your spending on vital repairs.

#5 – Superior hygiene

One of the major issues with high humidity is regards hygiene, because with high levels of humidity comes an increased risk of condensation. This, in turn, is followed closely by fungus and mould on both packaging and the product. This can spoil entire batches and result in a product which is unsafe to eat – something every food manufacturing business is keen to avoid.

3 Basic Types of Electrical Connectors

Any electrical equipment will have different types of electrical connectors within. Each connector comes in different shapes, sizes, and materials. Function is another key factor that classifies the connectors.

From connecting a wire to a board to joining key elements on a PCB, connectors play diverse roles and serve many applications. Despite their simple design, they connect and bring power/signals to the system. Key factors that determine the quality of a good connector is its reliability, signal integrity, speed performance, power rating durability, and ease of assembly.

Connector manufacturers offer an extensive array of tried and tested product solutions.

There a few common connectors which are worth the mention:

8P8C Connector

8P8C connector, where 8P8C stands for “eight positions, eight conductors” have eight positions, with corresponding conductors in the mating socket assigned to each. It is basically a modular connector and was primarily used in telephone wire applications. Today, they serve many applications and functions like being used to interface Ethernet jacks.

The 8P8C connectors have a male plug and a corresponding female socket connection. It carries eight contacts and when they get aligned with the corresponding eight conductors within the sockets, electrical signals get transmitted. Apart from Ethernet and telephone wires, they are also used in computer applications and other communication cables.

Generally, most modular connectors are technically named after the number of positions and conductors. They include sizes like -4-,-6-, 8-, and -10-. For instance, a 10P8C will have ten positions with eight conductors.

D-Subminiature Connectors

D-subminiature is much similar to 8P8C, as they are used in computer and play a critical function on modems. Though the name states “subminiature”, these are larger than most modern computer connectors. The connector has a D-shaped metal component that defines its shape and protects it. It also consists of two or more rows of pins with varying numbers in the male connector and a similar set of receiving ends in the female part. The male connector with a pin is called a plug whereas the receiving part that houses the contacts that connect these pins is called a socket. This connection is established to transmit electrical signals. This variant has the capability to provide protection against electromagnetic interference, commonly known as EMI.

USB Connectors

USB or Universal Serial Bus is a very common type of connector. They are small interfaces used to attach multiple devices to a computer. You can see at least two USB ports in any standard laptop that support external USB connectors and cables, while desktops have up to 4 USB ports in general. USB connectors gained much popularity and recognition, as it can be connected and disconnected easily while the device is still working. This contributed to its widespread use in computer applications that constantly require plugging and unplugging external devices, especially for transferring data.

Industrial Processes And Emerging Technologies

Technology has been playing an incredible role in transforming the way industrial processes are performed. Whether it is a machine-to-machine communication or augmented reality, technology has been helping industries in every possible way to streamline and automate their work. Emerging technologies, like 3D printing, robots, algorithms, etc., have the power to completely transform the existing manufacturing processes. Or, in other words, modern technology has the potential to make our lives better. A rapid increase in the level of sophistication in technology has a strong impact on the workforce.


Robots are being increasingly used to perform all sorts of industrial tasks. The developed parts of the world have witnessed a sharp rise in the demand for automated machines and equipment. Approximately, there are more than 2 million robots in use and the number is expected to rise quickly in coming years. Japan is leading the list of countries with the most number of robots. Recent years have witnessed a major decrease in the costs of automation and robotics.

Additive manufacturing

Additive manufacturing or 3D printing is an emerging technology that enables industries to manufacture three-dimensional objects. It is a process of building complex products by adding ultrathin layers of materials one by one. Currently, only selected items are being created out of a single material, for instance, medical implants and plastic prototypes. Comparing 3D industrial technology with that of traditional, additive manufacturing enables industries to manufacture new shapes without worrying about manufacturing limitations.

Autonomous technology

Autonomous technology, such as unmanned cars, is stretching the possibility of producing highly sophisticated industrial machines capable of performing the unthinkable. It has a great potential in making industrial processes seamlessly smooth with hardly any human intervention. Autonomous robots have already been deployed by a number of industries worldwide to perform quality control and inspection related tasks.

Augmented reality

Augmented reality is about the augmentation of the elements of physical world. By using handheld sensors, people can simulate various situations or, in other words, augmented reality enables us to create an illusion of reality. This technology can help engineers build incredible industrial solutions. One of the practical applications of this technology is the training of military recruits where they are tested with various virtual situations.

Conclusively speaking, new technologies are enabling engineers to develop intelligent machines that can perform multiple industrial tasks with great precision and speed. Companies need to invest in automation technology in order to maintain competitiveness and meet growing demand for innovation and modernity.

Protecting Storage Tanks From Lightning

Providing adequate and effective lightning protection for storage tanks constitutes a beneficial and cost-effective step in assuring both personnel safety and reliability. Fortunately, securing such protection is not difficult or complicated, and guidance is readily available. It helps to become familiar with some basic recommended practices and standards for reference. We will be referring to the National Fire Protection Association NFPA 780, Standard for the Installation of Lightning Protection Systems; the American Petroleum Institute API 545, Recommended Practice for Lightning Protection of Aboveground Storage Tanks for Flammable or Combustible Liquids; and the American Petroleum Institute API 2003, Recommended Practice for Protection Against Ignitions Arising Out of Static, Lightning, and Stray Currents.

Whenever considering lightning protection, it helps to fall back upon the three basic steps: bonding and grounding, surge suppression, and structural lightning protection.

BONDING AND GROUNDING. The first consideration is bonding and grounding. According to API 545, flat-bottom tanks are inherently self-grounding for lightning protection purposes. The mass of the tank and surface area of its bottom in contact with whatever material it occupies provides a sufficiently low-impedance path to conduct lightning currents without increasing the risk of ignition. This applies whether or not a non-conductive containment membrane is in place under the tank.

It should be noted that, although adequate for lightning grounding, the path to ground may be high resistance, rendering it unsuitable for AC power grounding. In the event of an AC power ground fault, the lack of a low-resistance return path may leave the tank energized. Therefore, we recommend at least one, and preferable one each 100′ of tank perimeter, “solid” connection to ground. This usually consists of a conductor attached to a grounding tab at the base of the tank shell running to a ground rod or to the grounding grid.

Bonding is simply a matter of electrically connecting different masses of inductance (metallic masses) together to maintain them at the same potential, to equalize changing potential, and to provide a path for lightning current between them.

The major area of concern is obviously the floating roof. On an external floating roof tank, there are three lightning events that can cause arcing between the roof and tank shell. The first is a direct strike to the roof itself or its appurtenances. In this case, all of the lightning energy must flow across the seals to the tank shell and to ground. The second is a direct strike to the top of the tank shell. In this case, the lightning energy flows down the shell to ground, and the roof potential must be equalized to that of the tank shell. In the third case, a nearby strike changes the potential of the tank shell, and much less difference in potential must be equalized between the roof and tank shell.

Lighting energy consists of two components with an intervening transition component. The first is a high-energy, short-duration surge of energy. The second is a lower-energy, longer-duration event. The first segment, although conveying high amperage, is so short that it does not normally cause ignition. Think of passing your finger quickly through the flame of a candle. However, the second segment consists of a few hundred amps (about equivalent to the electrical service into your home) over half to three-quarters of a second. When faced with resistance between the floating roof and tank shell, it can easily produce sufficient heat to cause the ignition of any flammable gasses present. Think of your kitchen stove on steroids.

Therefore, two types of conductors are required between the floating roof and tank shell. The first is a sliding contact between the roof and shell, and is intended to handle the short-duration, high-energy pulse. This has historically been addressed by the use of shunts between the roof and tank shell. These were developed to overcome the shortcomings on non-conductive seals. However, most modern tanks employ metallic shoes as the primary seal between the roof and shell. These shoes have many times the surface area of shunts. According to wording which will presumable be adopted in the next revision of both NFPA 780 and API 545, the presence of primary metallic shoe seals will negate the requirement for shunts.

Shunt Primary Metallic Shoe Seals

However, contacts sliding on contaminants produce arcing and sparking, raising the need for a second type of conductor, the bypass conductor. This is a hard electrical connection between the floating roof and tank shell. Because the bypass conductor must be of sufficient length to allow full range of motion of the tank roof, it requires time to become conductive. When it becomes conductive, it quenches any arcing at the sliding contacts, and conducts the long-duration, lower energy second segment of the lightning strike.

Bypass conductors

Another area of concern is thief hatches. The hatch itself rests on a rubber seal and is connected to its collar by a pin-type hinge. In the field, we have measured a high resistance between the thief hatch and its collar. Lightning current flow across that resistance is capable of producing sufficient heat and arcing to cause ignition. Therefore, a flexible jumper between the hatch and collar should be added to each.

SURGE SUPPRESSION. The second step in securing adequate protection is surge suppression. Any conductor running to or from a tank is perfectly capable of introducing all types of mischief. A surge suppressor is simply a device that keeps that from happening. Typical conductors found on a tank include AC power for site lights, pumps, valves, etc., and for data collection including levels, temperatures, flow rates, etc. Surge suppressors should be installed at the tank end of such conductors and also at their origin. This will limit the transient gremlins in their mischief.

STRUCTURAL LIGHTNING PROTECTION. The third step in securing protection is structural lightning protection. When we think of structural lightning protection we normally think of lightning rods on the roof of a building. It is important to remember that the purpose of a lightning rod system is to convey lightning energy around a non-conductive structure, such as a house or barn, thereby keeping that structure from burning down.

Note that there is absolutely no benefit to installing lightning rods on a tank. According to NFPA 780, the tank itself is inherently self-protecting. There are three components that make up a lightning rod system: the lightning rods, conductor system and grounding system. On a tank, the tank itself is of sufficient thickness to be substituted for the lightning rods, the shell is of adequate cross section to be substituted as the conductor system, and the site ground is more than adequate for lightning protection purposes. Therefore, the tank is self-protecting without the need to install additional components. Lightning rods would only tend to attract lightning to the tank.

There is, however, a technology alternative to conventional lightning rods. These are streamer-delaying air terminals. These air terminals, colloquially known as “fuzzy ball™” lightning rods, are designed to interrupt the lightning completion process by delaying the formation of lightning-completing streamers from objects on the surface of the earth.

A lightning strike begins with the formation of stepped leaders from the base of the storm cloud. These leaders jump in steps of around 150′, working their way downward towards the surface of the earth. When they reach to within 500′ or so of the surface, they begin pulling streamers of ground charge off of objects on the surface. Whichever streamer meets a stepped leader first determines what gets hit. As the ground charge builds on a streamer-delaying air terminal, the sharp points break down into corona under a low potential. When it comes time for a streamer to form from a protected object, the ground charge that would constitute the streamer has been partly dissipated into the atmosphere, thereby reducing the likelihood of a direct strike.

We use NFPA 780 as the design standard for protecting a tank. As the tank contains flammable material, we reduce the diameter of the rolling sphere to 100′, reducing the spacing between air terminals to jus over 12′. We install them around the perimeter of the tank shell on the foam injection plates and rim, and on the gauging platform. We also install them on the walkway handrail, if one is installed.

Streamer delaying air terminals on storage tanks

API 2003, Annex C, Direct Stroke Lightning Protection, C.1 notes that conventional lightning protection systems do not protect against indirect lightning currents or induced voltages. These are both major causes of ignition, particularly in production tanks. It further notes in C.2.1 that, according to vendor claims, streamer-delaying systems may have some benefit in protecting against indirect lightning currents of induced voltages. This type of performance is obviously preferable.

In the real world, we have seen a very high success rate with operators installing this type of system. Indeed, the cost has been justified many times over in both actual savings associated with extinguishing a fire and reducing lost time in service.

New Technologies: A Solution to Improve Profitable Growth

The quick pace of technological advancements explains clearly why manufacturers focus on getting innovative products to market. An insatiable drive for innovation creates a strain on companies and make them look constantly for new techniques to manufacture products. Taking this into account, how can you profitably satisfy your customers and grow your business? The following discussion will help you understand how you can achieve profitable growth when incorporating new technologies into your new and existing products.

Your customers always want to gain an edge from the latest technological updates no matter your customers are individuals or businesses. As a manufacturer, the only solution you have is to add new methods of production as efficiently and as quickly as possible and ensure on-time delivery. Innovative and modern manufacturing techniques can be associated with lighter materials, energy-efficient designs, faster processors, more efficient software or hardware features, etc.

A robust product lifecycle management system will enable you to integrate manufacturing processes, supply chain, and procurement. It will eventually lead to an increase in the efficiency of your business. Fundamentally, innovation means implementing something new to your business. It could be associated with:

  • Adding value to existing products and services in order to gain a competitive edge
  • Developing improved products and services to meet emerging consumer needs and requirements
  • Improving or replacing traditional business processes to materialize higher productivity and efficiency
  • Extending the functionality and quality of existing products

Before you invest in any technology, carry out a careful assessment to determine which industry-specific solutions are best suited to your business. From accounting and supply chain management to human resource and enterprise resource planning, you can find readily available and affordable manufacturing solutions. Every business has its own unique strengths and weaknesses. You need custom engineering and management solutions to meet your unique requirements.In order to achieve sustainable growth, a business must carefully examine its sense of purpose and make sure the organization serves it well. An inspiring purpose is all about:

  • A strong engagement within a company and its stakeholders
  • Non-stop, pragmatic innovation
  • A consistent and constant sense of focus

Automation is the single most significant factor that can help manufacturers meet their production and growth objectives. Automated machines, industrial robots, intelligent sensors and control systems, advanced quality control (QC) systems are few examples of innovative manufacturing techniques.If you want to build a scalable business, you have to understand how critical it is to build and implement efficient machines capable of operating intelligently and independently. The right technology can dramatically improve how you manage your business. Consult a reputable manufacturing and engineering solution provider in order to eliminate complexities and inefficiencies from your production system and achieve profitable growth.

Pumps – Classification and General Concepts

Pumps are usually classified into two broad categories:

Rotodynamic pump and Positive Displacement Pumps

Rotodynamic Pumps

In these pumps, a rotary device with blades, called the impeller drives the liquid. The liquid gets kinetic energy in the process. The kinetic energy is converted into pressure by means of the design of the pump.

These can be divided into:

Centrifugal pumps: Here, the impeller with blades drives the liquid radially outwards towards the casing. The liquid gets pressurized as it exits the pump.

Axial Pumps: Here, the liquid is driven axially by the impeller. The flow of the liquid is parallel to the axis of the impeller.

Positive Displacement Pumps

Here, the liquid is drawn into a chamber, pressurized and expelled at the discharge side.

These are, in turn classified, into two types:

Reciprocating Pumps: Here, a piston moves inside a cylinder. The piston creates low pressure when it moves up. This sucks the liquid inside. Once inside, the piston moves down and pressurizes the liquid which is discharged through a port. The handpump used to lift water is a reciprocating pump. Eg. Plunger Pump

Rotary Pump: Here, two rotating gears or screws move inside a casing. As the screws or the gears move, the liquid is progressively taken inside. The cross section of the casing is reduced as the liquid moves. This causes pressure at the discharge side. Examples: Screw and Gear Pumps


The Capacity of the pump refers to the discharge rate of the pump at a specific head.

It is generally expressed in cubic metres per hour, second or minute. Sometimes, it is also represented in litres per second or hour.

Specific Speed

The Specific Speed is a method of describing a pump by parameters such as the speed, head and flow rate. The Specific Speed helps in deciding the type of pump for a specific application. It also helps in comparing different types against a single requirement.

The Specific Speed is the speed at which a geometrically similar pump would have to run to deliver a flow rate of 1 liter of fluid at a head of 1 meter.

A single stage centrifugal pump consists of an impeller and a volute. The liquid is drawn inside at the centre of the impeller and discharged radially.

Multistage centrifugal pumps have more than one impeller and volute. A three stage multistage pump will have three impellers and three volutes. The output of the first impeller will be fed to the input of the second impeller and so on.

The multistage pump can generate more pressure than a single stage pump.

For a given output pressure, the multistage pump will have impellers of smaller diameter. The efficiency of a multistage pump will also be greater than a single stage pump.

It is possible to retrofit a single stage pump assemble with a multistage assembly with minimal rework in the piping.

In certain multistage pumps, there are provisions to by pass an impeller. This may be useful for applications such as in firefighting where the pressure of the liquid will be different at different situations (based on the height of the building). In such cases, the last impeller may be bypassed and the output can be drawn before the last impeller.

Multistage pumps will have more vibration than single stage pumps.