What is a centrifugal pump?
Centrifugal pumps are the most common type of pump, with dozen of different configurations available including: fire pumps, end suction pumps, chopper pumps, grinder pumps, magnetic drive pumps and many more.
Centrifugal pumps use one or more impellers which attach to and rotate with the shaft, providing the energy that moves liquid through the pump and pressurizes the liquid to move it through the piping system. They are usually quick to install, require less maintenance than other alternatives, and are generally easy to repair.
Centrifugal pumps are usually the best choice for lower viscosity (thin) liquids and high flow rates. They are also used in many residential, commercial, industrial, and municipal applications. Multi-stage centrifugal pumps have more than one impeller, and are used for applications that require higher pressure or head.
They generally work within the following ranges:
- Flow rate ranges between 5 and 200,000 gpm
- Total head (pressure) ranges between 10 and 7,500 ft
- Horsepower ranges between 0.125 and 5,000 hp
There are a wide variety of materials of construction, ranging from various plastics and cast iron or stamped stainless steel for lighter duties - to bronzes, stainless steels, exotic alloys, and specialty plastics for more corrosive, abrasive, hygienic, or other difficult applications.
Piping connections on centrifugal pumps are available with standard pipe threads on smaller sizes, and flanges on larger sizes. Specialty connections are available from some pump manufacturers for particular applications. The normal drivers supplied are A.C. induction motors, but some manufacturers offer pumps with D.C. drives or adaptable to other power transmission devices such as engines and gear boxes.
How do they work?
A centrifugal pump works by:
- First the pump directs the liquid in the system into the suction port of the pump and from there into the inlet of the impeller.
- The rotating impeller moves the liquid along the spinning vanes, which increases the velocity energy of the liquid.
- The liquid then leaves the impeller vanes and then moves into the pump volute or diffuser casing, where the high velocity of the fluid is converted into high pressure through a diffusion process.
- The fluid is then guided into the discharge port of the pump and from there out into the system, or on to the next stage in the case of a multi-stage pump.
Blackmer company manufacturers its System One centrifugal pump for high volume, severe process industry applications such as liquid terminals, mining dewatering, wastewater, and chemical process. The centrifugal pump features a heavy duty shaft and oversized bearings that allow for a larger load capacity.
The System One pump is available in variety of materials to meet the demands of most industrial process applications, can handle flows up to 4,500 gpm, total head to 780 ft, and fluid temperature to 750 degrees F.
Griswold offers centrifugal pumps for a wide range of process, industrial and water/wastewater applications. The pumps are used in the chemical process, pulp and paper, power generation, swimming pools, water park markets, and more.
The company’s 811 ANSI process pump is compliant with the ANSI B73.1m standards and can handle fluids to 500 degrees F and flow rates to 7,500 gpm at 920 ft of head. Griswold also offers its E, F, and G series centrifugal pumps, which are end suction configuration and ideal for water and wastewater applications. The pumps can handle up to 3,000 gpm and press to 134 psig.
Patterson manufacturers a wide range of centrifugal pumps for the fire protection, HVAC, industrial, water and wastewater, plumbing, and flood control markets. Patterson offers vertical turbine, end suction, fire, horizontal split case, vertical in-line, mixed and axial flow, solids handling sewage pumps. The pumps have flow capacity from 50 gpm to over 700,000 gpm.
- The Patterson H2O Works™ pumps are built to move sludge, raw unscreened sewage, and contaminated trashy fluids. Capacities range from 150 gpm to 12,000 gpm, with heads in excess of 250 ft.
- The company’s H2O Works™ Municipal Pumps are built for major municipal sewage and storm water systems. They have standard capacities ranging from 150 gpm to 500,000 gpm.
- Patterson’s H2O Works™ Vertical Turbine pump for the industrial, municipal and power applications. The pumps can handle flows in excess of 30,000 gpm with discharge heads from 6 inch to 14 inch. Bowls are available in diameters ranging from 12 inch through 40 inch.
- Patterson manufacturers its H2O Works™ Type “F” pumps for wastewater applications with suspended solids. The type “F” have flow capacities range from 500 gpm to 100,000 gpm, with heads to 150 ft.
- Patterson makes its Sentinel™ Vertical Turbine Fire Pump for fire suppression applications. The pump does not require priming and has flow ranges from 500 to 5,000 gpm, with pressures in excess of 350 psi.
Price® Pump is a leading manufacturer of centrifugal pump technology. The company produces dozens of products for a wide range of applications including chemical process and transfer, wastewater treatment, agriculture, OEM, and cooling water. Price’s centrifugal pumps have a flow capacity to 1100 gpm and max head to 300 ft. The pumps are also available in a range of materials of construction, including bronze, cast iron, and 316 stainless steel. The centrifugal pumps are built in several configurations, including multi-stage, close coupled, self-priming and more.
Ruhrpumpen is a global manufacturer of centrifugal pumps. The company produces nearly every type including axial and mixed flow, vertical turbine, submersible turbine, end suction, horizontal split case, multi-stage, ANSI process and much more. The pumps are built for a wide range of applications including power generation, oil and gas, industrial, fire prevention, chemical processing, mining, and water/wastewater.
The company’s centrifugal pumps are offered in several different configurations, including: overhung, between bearings, vertical, and fire pumps.
Vaughan manufacturers a wide variety of centrifugal chopper and Triton screw pumps. The chopper pumps are available in a variety of centrifugal configurations including submersible, cantilever, self-priming, end suction, vertical, and more.
The pumps are used in a wide variety of applications were a chopper devise is needed to handle solids-handling fluids such as municipal, industrial processing, and agriculture. The pumps are available in various materials of construction and can handle flow rates to 12,000 gpm.
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