You don’t need to have been in the business of pump distribution and services as long as we have to know that not all pumps are created equal!
There are numerous differences in capability between different types of pumps, and one of the most basic splits is between dynamic and positive displacement pumps. These are considered completely separate categories in the ‘family tree’ of pump classification.
So, we wanted to take a moment to talk about the differences, and which types of pumps fall into each category.
Dynamic vs Positive Displacement Pumps: What’s The Difference?
Broadly speaking, the difference comes from their method of operation. Dynamic pumps use direct mechanical methods – typically a propeller or impeller – to move liquid. Positive displacement pumps, on the other hand, use air or water pressure to achieve the flow, such as a bellows-style system.
Now let’s look at a few specific examples of each.
I. Dynamic Pumps
The most common type of dynamic pump is the centrifugal pump. In their most basic configuration, there’s an inlet followed by a rotating impeller that adds movement to the liquid, and the outlet it comes out of.
Submersible pumps are another example, with an impeller housed within the unit which creates the kinetic energy needed to push liquids upward. Beyond being waterproofed, the big difference between these and centrifugal pumps is that submersible pumps typically use water pressure to at least partially power the impeller, rather than only using electricity.
II. Positive Displacement Pumps
The most common design of positive displacement pumps relies on air-operated diaphragms, called AOD Pumps. A (typically mechanical) system operates the diaphragm, pulling in air and then pushing it through the system to create liquid flow.
Possibly the oldest displacement pump is the venerable piston pump, which can be operated manually or by hand. The piston pushes air in and out of the pumping system to create positive pressure.
Another example is the gear pump which uses a series of gears to create displacement pressure. These come in and out of mesh, creating differences in pressure that drive the flow.
Which Pumps Are Right for You?
FloRight Pump & Controls has more than 30 combined years of experience in pump distribution, sales, repairs, and upgrades. Our experts can look at your desired usage case and put together the perfect pumping system for your needs. Contact us for a consultation!
