Pumps 101: What Are the Components of a Pump?
Pumps are used in thousands of different functions around commercial and residential properties in New York City. Why is it wise to know the components of a pump? If the pump malfunctions or something doesn’t look right, you can better describe the issue to a pump specialist. The pump pro will then be able to estimate the time involved for repair and bring replacement parts, if applicable. Here’s an introduction to the components of a pump so that you can perform your job as a landlord or building manager more easily and efficiently.
Pump Basics
Definition and Types
A pump is a mechanical device designed to move liquids, gasses, or air using pressure or suction. In property management, pumps are used for everything from plumbing to heating to fire suppression.
There are two basic types of pumps based on the components inside: positive displacement and centrifugal (see parts below). Positive placement pumps use an interior element to displace fluid. Centrifugal pumps use centrifugal force, which is the force created from spinning in a circular motion, to move liquid.
You may also subcategorize these two types of pumps by their location (such as an inlet pump), by their function (boiler feed, vacuum, etc.), or by their position in a process flow chart.
Components Common to All Pumps
Three essential parts
All pumps, regardless of what type they are, have three essential components:
- Inlet – Also called the suction side on some pumps, this is where liquid enters the pump. It is the point of lowest pressure.
- Casing – This contains the liquid being moved, as well as all the interior components. It is also sometimes called the pump housing, shell, or cover. It is a protective and supportive element that also keeps liquid from leaking out. Preventing leaks is essential not only to prevent fluid loss but also to keep any caustic or dangerous fluids from harming people or the environment.
- Outlet – Also known as the discharge side, this is where liquid exits the pump. Liquid at this point is at its highest pressure in the system.
Positive Displacement and Centrifugal Pump Parts
Pistons vs. impellers
The interior parts of a pump will differ depending on if it is a positive displacement or centrifugal pump. As mentioned above, a positive displacement pump uses a component to displace fluid. This is most commonly a piston, but it may also be a flexible diaphragm, or a screw mechanism, such as those found in rotary pumps. A screw pump, by the way, is the oldest type of pump found in history, dating back to 250 BC in Ancient Greece and based on the principles of scientist and inventor Archimedes.
For example, in a piston-type positive displacement pump, fluid enters the pump through the inlet, pushing the piston back. A stroke of the piston then pushes against the fluid, closing the inlet and forcing the fluid through the outlet.
In centrifugal pumps, an impeller is the key component. The impeller, which looks a bit like a fan with vanes or blades, spins fluid that has entered the pump through the inlet. The centrifugal force created by the spinning of the impeller forces the fluid to exit the pump through the outlet.
Impellers may be axial flow (fluid moves parallel to the shaft) or radial flow (fluid moves perpendicularly to the shaft). Impellers can also be open or closed, depending on if the vanes are exposed on one side or completely covered (shrouded).
Auxiliary Parts
Power and safety
There are multiple other parts to a pump that contribute to its power and safety. Since we rarely power pumps by hand anymore, one of the most important is a driver. This provides power for the pump’s action, and nowadays, that’s usually an electric motor. However, hydraulic power, steam, and internal combustion may also provide power.
A shaft transfers power from the driver to the components that move the liquid, like a piston or an impeller. Connecting the driver shaft to the pump shaft is a coupling. The pump shaft may be fixed, meaning the speed doesn’t change, or it may be variable, meaning the speed can be changed without making parts adjustments.
A lubricating system is often present to keep bearings from wearing down and from overheating by coating them in oil, grease, or other lubricating materials. Bearings support and align the moving parts of the pump and reduce friction at multiple points. There are many different types of bearings:
- Roller bearings (cylindrical shaped rollers)
- Ball bearings (the most familiar ball-shaped type)
- Sleeve bearings (designed to float and used in high-speed pumps)
- Babbit bearings (a type of sleeve bearing coated with Babbit metal, an alloy)
- Pivot shoe bearings (AKA tilt shoe bearings or Kingsbury bearings, used in axial flow impellers)
There may be a strainer present to remove any solids that collect in the pump to prevent damage. Other parts you will likely encounter include:
- Seals – gaskets, O-rings, or packing to keep fluid in and contaminants out
- Fittings – connect different parts to each other
- Probes, sensors, and gauges – provide information on the pump’s performance and the fluid inside
- Valves – control the flow of liquid inside the pump
- Mounting devices – affix the pump where it will be used and prevent vibration
A great way to learn more about the pumps you use on your property is to observe when one is being repaired or to look at the parts on an old pump when it is being replaced.
Antler Pumps are your New York City experts when it comes to pump maintenance and repair. We’re happy to answer all your questions about your pumps or perform requested services. Call us at 212-534-2500 or use our convenient online form to schedule an appointment today.