What is a pump ?

I am a computer science and mechanical engineer working for a large pump manufacturing in the Midwest. I decided to start posting this articles to keep track of some of the common questions I get asked by customers. The one in the title seems easy to respond but it is not. Please keep reading to find out what a pump is...

I always get surprised by the questions I get from customers in the different industries that use hydraulic systems to move fluids around the world. One of the latest questions I received from a process engineer is: "What is a pump ?"

Although I can easily direct them to Wikipedia: https://en.wikipedia.org/wiki/Pump, and knowing that there are countless resources online and in libraries around the world, I usually take the time to explain what is a pump, how it works, some of the different technologies out there, manufacturers, etc...

I also take the time to explain that each different application may require a different technology, "A Blackmer pump for dewatering ?", "Why ??", lol.... There are also different materials of construction, equipment limitations and different engineering requirements. And even though this is an old industry (This is one of those industries entrenched in the US rust belt), there are some new innovations out there.

So, the definition from Wikipedia is actually semi-correct: A pump is a mechanical device designed to move fluids (liquids or liquefied gases) and slurries. Note that, unlike Wikipedia, I did mention that a pump moves liquefied gases, not gases. Compressors are designed to move gases (and air is a gas), although they are sometimes called pumps too (In example, in an aircraft, a turbine powers an air compressor for propulsion via a nozzle).

There are many different types of pumps in the market. The question above, "what is a pump", is usually followed by, "What type of pumps do you handle ?". My usual response is, initially in my career I specialized in centrifugal pumps in different industries, lately I have been working with reciprocating and positive displacement in oil and gas and other industries.

Of course, after my response, subsequent questions about these different technologies ensue. Again, there are countless articles and resources online and in books, however; I will take the time to write about these technologies, hopefully summarized, in the near future.