Splitting Hairs Over Split Case Pumps

Deciding on the best pump to use for your business is like deciding on what to eat when you’re really hungry.  It is almost impossible to figure out whether a horizontal pump is better than a vertical pump.  Before making a decision on the type of pump you need, create a plan on how you want your operation to work.  Get organized, so your pumps will work for you and not against you.

What is a Split Case Pump?

Split case pumps are one of the many kinds of centrifugal pumps.  This type has a top and bottom with an impeller between the shaft bearing on each end.  Split case pumps are your standard end-suction with an overhang because the bearings are to one side which supports the impeller that is inside of the casing. 

The first centrifugal pumps were developed in 1905.  Throughout the years, pumps have evolved to become more resistant to external conditions like rust and rain.  In 1940, Peerless (available through Grundfos) installed a split case pump in the field.  Overall, pumps are used to move fluid from one place to another.  Split case pumps move large quantities at low to medium pressures. 

Why should you use a split case pump?

If you have a large quantity of water to move, split case pumps are your best bet.  They are used in all kinds of industries including marine, wastewater, aerospace, mining, pharmaceutical, and more. Here are some reasons why a split case pump is better than the rest.

1.     The top half of the pump is easy to remove.  You don’t need to worry about disturbing the piping or tearing the pump apart to inspect the rotor.  Put away the owner’s manual.  Because everything is easily accessible, you can diagnose a problem easily. 

2.     Horizontal split case pumps have a smaller footprint especially when compared to a frame mounted pump with the same rating (most of the time).  This means you require less space to use this kind of pump.  If you are limited to the area because your rent would skyrocket if your manufacturing plant were any bigger, using pumps with smaller footprints maximize your space for more efficient use.

3.     The dual section impeller design allows for a lower net suction and lower axial thrusts.  Most split case pumps like the one available from American-Marsh Pumps can handle higher than boiling temperatures (225 degrees F), having two chambers for the fluid on either side of the impeller helps distribute the heat better than most kinds of pumps. 

4.     A split case pump works better when it is close to the water or other fluid sources.  The design has a shorter shaft which results in low deflection.  Controlling the water in many environments is conducive to your productivity.  You need a pump you can rely on as it works hard so you can focus on other parts of your operation.

When is a split case pump not the best idea?

With any tool, there are disadvantages.  It's all about finding which pump is right for the job and a split case pump is not any different.  You probably have your finger on ESP’s website to order one right away, but consider whether the split case pump is good for the job at hand.  Either way, the team at ESP will point you in the right direction to get the pump that suits your needs.  Here are some not so good selling points on split case pumps:

1.     Split case pumps require short shafts.  Installing horizontal elbow’s suction side will cause asymmetrical pressures that will mess with the bearing and seal’s life.  A split case pump works well when it is connected as close to the source of water as possible.  By adding twists and turns to the pipes, it makes it harder for the pump to function.

2.     The casing does not have a confined gasket, so they are limited to the amount of horsepower and pressure used.  Most of the manufacturers who work with ESP like EBARA have comprehensive guides that will let you know what your limitations are in regards to temperature, pressure, and more. 

3.     The split case pump might have increased costs because it has two seals or two stuffing boxes.  If you have twin babies, you know that you’ll need two of everything.  Like two cribs, two strollers, and double the diapers.  A split case pump is no different.  To maintain the pump, you’ll need two of everything. 

4.     The pump is sensitive to problems with ring clearances.  Luckily, because you don't have to tear the pump apart to see what is going on, it is easily resolved, but if one side is wearing, it will cause some lag in the overall function.

5.     Split case pumps are no different than several other kinds.  They require some maintenance.  It is recommended that the shafts are rotated 10 to 15 times every one to three months.  This helps spread the lubrication.

If you’re leaning towards getting a split case pump, keep in mind that you need to be near the water or fluid source.  The shafts are short with no twists and turns.  It is best used when you’re using a split case pump for significant amounts of water that need to be propelled close to the source.

Pumps available through ESPs providers are usually customizable to your business.  Creating a plan for your business will make it easier to understand what kind of pump system you’ll need.  Split case pumps are ideal for handling a lot of water that needs to move in your operation. They are easy to maintain in comparison to other pumps because you do not have to take the whole thing apart to check out the rotor.  They do not take up a lot of space, so they have a smaller footprint.

Call ESP today to build a smart plan for your plant for all of your pumps, pipes, shafts, and more.