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From Fluid Handling

While not as common as centrifugal pumps in the CPI, gear pumps play important roles in handling many of today’s more difficult-to-pump fluids. Because they operate at lower speeds — generally, 900 rpm or less — their seals and bearings tend to last longer than those of centrifugal models. In addition, unlike centrifugal pumps, gear pumps’ flows are independent of their systems’ pressure curves, and they can handle a wider range of viscosities.

Although high-flow, low-head applications remain the domain of centrifugal pumps, the use of gear pumps is increasing in the chemical process industries (CPI). While some application boundaries between gears and centrifugals are blurring, there are some crucial differences between the way the two are operated and maintained — for example, where pressure relief is concerned. This article provides a general summary of gear pump characteristics and applications, highlighting critical aspects of installation, operation and maintenance.

Generally, gear pumps are used in both metering and general fluid transfer applications. Metering units tend to be smaller and built to closer tolerance levels than general transfer pumps.

In the past, most applications ran at fixed speeds, but today, variable speed drives are gaining popularity. Standard industrial pumps are available with...


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© 2014 Chemical Engineering

Products & Services
Double Diaphragm Pumps
Double diaphragm pumps are positive displacement pumps that compress fluid by decreasing the volume of a chamber containing the fluid.
Hand Pumps and Foot Pumps
Hand pumps and foot pumps are manually operated pumps that can driven by hand or foot via a handle or lever. 
Mechanical Vacuum Pumps and Systems
Mechanical vacuum pumps and systems contain devices such as pistons, claws, scrolling spirals, and diaphragms to isolate and compress air.
Condensate Pumps
Condensate pumps are used to collect and transport condensate back into a steam system for reheating and reuse, or to remove unwanted condensate from an HVAC or appliance collection pan.

Topics of Interest

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