Metering Pumps
What is a metering pump?
A pump that is designed to move fluids at precise flow rates. Most have the ability to set and adjust the flow rate with a hand dial or digital touch pad. Flow rates for metering pumps are usually quite low due to the nature of the application, with most flow rates being rated in gallons per hour (gph) rather than the traditional gallons per minute (gpm) used for most pumps.
The most common types are diaphragm pumps, with the diaphragm mechanically or hydraulically actuated, or moved via a solenoid. However, other types of positive displacement pumps such as piston pumps, peristaltic pumps, plunger pumps, or several other rotary pump types may also serve as metering pumps.
Metering pumps generally work within the following ranges:
- Flow rate ranges between .001 gph and 20 gpm
- Total head (pressure) ranges between 10 and 300 psi
- Horsepower ranges between 0.125 and 5 hp
How do they work?
There are two main types, both of which may adjust the flow rate by any number of different pumping mechanisms:
1. Variable displacement pumps adjust the flow by changing the amount of fluid that enters the pump, while the motor always runs at a constant speed. They often do this by adjusting the stroke length, or in some cases the amount of hydraulic fluid that is bypassed.
2. Fixed displacement pumps adjust the flow by changing the speed of the motor, while the same amount of fluid is displaced with each revolution.
Where are they used?
Metering pumps are used wherever the flow rate of a liquid needs to be regularly measured and adjusted to precise levels. They’re most commonly used to pump treatment chemicals in water treatment applications, such as treatment of water for drinking, swimming pools, boilers, cooling towers, or in treatment of wastewater. The treatment chemicals are pumped into the water to adjust the pH, alkalinity, and to disinfect the water.
They are also used in food processing plants for blending of liquid ingredients, in process metering applications where one chemical needs to be added to another in precise amounts, in pipelines to decrease the frictional losses as the oil moves through the line, and in various laboratory and medical applications.
Here are a few metering pump manufacturers to consider.
Other related Pump Types include: pressure pump, high pressure pump, chemical pump, water pump, industrial pump.
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Industry Updates
According to a company press release, CLYDEUNION Pumps has been awarded a contract by Kindasa Water Services to supply pumps for a desalination plant in Saudi Arabia.
Agilent Technologies Inc.has acquired P.V.R. s.r.l., a long-established vacuum pump manufacturer based in Valmadrera, Italy.
Grundfos is now the official pump and pump systems provider for the Kansas City Royals.
Pump Tweets
Bell & Gossett sets the Fall 2011 course training schedule for its Little Red Schoolhouse Education Center in Morton Grove, Illinois. The seminars deliver various pump and system topics to engineers, contractors and facility maintenance professionals. Visit http://completewatersystems.com/brands/bell-gossett/ for more details.
Lufkin Industries plans to purchase Zenith Oilfield Technology. Zenith is a developer of systems for down-hole monitoring, data gathering and control systems. The company also offers real-time optimization and control devices specifically for electric submersible pumps (ESPs) and progressing cavity pumps (PCPs).
Frost & Sullivan has honored NETZSCH Pumps & Systems with the 2011 Best Practice Award for increased customer benefit. NETZSCH's customer focus and product innovation were a few key factors in winning the award. NETZSCH is a leading manufacturer of progressive cavity pumps, screw pumps, lobe pumps, metering pumps and other equipment.
KSB introduces immersion variant of high-pressure pump. The new pump, called Movitec VCl, is a vertical, multistage centrifugal pump that can be used for handling coolants, condensate and lubricants for machine tools. The pump has a max flow rate of 27 m3/hr and the maximum discharge head is 250 m.