For 2,000 plus years, inventors and engineers have constantly researched and refined various pumps for moving liquids and sludge. The first actual pump – Archimedes’ screw pump – invented in 200 BC for pumping water – is still in use today.
Over the centuries, engineers stayed busy designing highly specialized pumps for different jobs. The agricultural, shipping, chemical, petrochemical, mining, and water supply industries all use pumps.
Today, one of the most widely used and versatile pumps is the vertical turbine pump – developed around 1900.
Let’s look at what’s involved in designing vertical turbine pumps – and see why they are essential in so many critical applications.
What: Vertical Turbine Pump
All vertical turbine pumps are a type of centrifugal pumps designed for transferring liquid from an underground reservoir, a well, or a barge. Sounds simple, right?
But let’s say that water is a long way down -1,000 feet or so. In that case, using a multistage (more about that later) deep well vertical turbine pump is required.
Because you aren’t going to be able to service the pump’s motor if it’s 1,000 feet down, the motor sits at the top of the pump. The motor drives a vertical line shaft, which in turn rotates a flow impeller. Let’s run through the actual workings.
The Pump’s Motor
Submersible pumps have their motors adjacent to the pump, which means submerging the pump and motor in whatever liquid it’s pumping. With a deep well pump, that’s not ideal. In addition, servicing a submersible pump’s motor means disassembling the whole installation.
Another disadvantage of submersible pumps is that they push water to the surface. And there are limitations on how high submersible pumps can push the water. Not so with a vertical turbine pump.
Putting the motor at the top of the pump – like the pumps from ERL Marine, a leading national pump company, makes performing routine maintenance far easier. The design also means a wider choice in motors, like gas, diesel, or electric power.
Bottom to Top
At the very bottom of the pump is the suction bell. That’s where the liquid – let’s say water – enters the pump. Driving the impeller and accelerating the water is the line shaft (powered by the motor atop the pump). Once accelerated by the impeller, the water moves into the diffuser bowl sitting above the impeller.
That process converts the water from a high velocity to a high-pressure state. This allows the pump to draw the water towards the surface. Bringing water up from very deep wells is possible using multiple stages of impellers and diffuser bowls.
Once the water has passed through the last impeller/diffuser stage, it’s drawn up through the wellbore to the surface. From there, the water passes through the discharge heads. Piping sends from there to it where it’s needed.
There’s another advantage of these pumps. The same liquid being pumped is also lubricating the shafts, bearings, and impellers. That eliminates another potential trouble spot.
Construction and Engineering
Since these pumps are capable of moving large amounts of liquid quickly, the quality of the construction and engineering is critical. And, of course, the high pressures and high volumes involved require rugged components.
And these pumps can be quite large. Flow rates ranging from 50 gallons to minute (GPM) up to 30,000 gallons per minute or larger are common. The size of the discharge can be 8 – 12″ or more.
Using cast iron is typical in many pumps’ construction. However, a far better material is ductile iron – which gives twice the strength. Another excellent material for specialized applications, including corrosive liquids, is 316 stainless steel.
Using computation fluid dynamics (CFD) software, design engineers optimize a pump’s components for efficiency and strength. Testing the pumps is critical and is done at our Pump Test Facility in Houston, TX is another step in the process. This rigorous design and testing mean that the pump’s end-users get the best efficiency and performance for their application.
One of the reasons vertical turbine pumps are so widely used is that they are highly versatile. Adjusting flow rate (GPM) and pressure to meet the specific application is part of the design process.
By adding additional stages (those impeller and diffuser bowl combinations again) and raising the pressure, vertical turbine pumps can pump liquids in situations submersible pumps can’t.
The versatility of vertical turbine pumps means they are working in a wide variety of applications. Often a combination of high flow and high pressure is required. Let’s run through some of the more common uses of vertical turbine pumps.
Municipal water systems frequently use vertical turbine pumps in deep wells or groundwater applications. With their ability to boost pressure, cities also use them above ground to provide better flow rates.
Using turbine pumps to pump well water and then irrigate multiple acres is common in the agricultural field.
Vertical turbine pumps are essential in the marine industry, using vertical turbine pumps to move and discharge liquids onboard bluewater ships and inland barges.
In large industrial applications, turbine pumps move large quantities of water and other liquids used in processing. And in the power generation field, plants using them in cooling towers is common.
With the motor driving vertical turbine pumps located above ground, these pumps aren’t limited to using electrical power. So in remote areas without available electricity, diesel or gas engines are often used to run the pump motor.
Deep Well Vertical Turbine Pumps
Now that you know more about what a deep well vertical turbine pump is and how it works, contact us to find out how we can solve your commercial marine pumping needs.
Since we started in 1970, we’ve patented more than 30 commercial marine designs. In addition, our research and development engineers work closely with our customers. That allows us to design and build equipment matching their needs.
Our commitment to engineering innovation and manufacturing excellence is second to none. ERL Inc. is America’s leading tank barge equipment provider with 50 plus years of experience and installations on more than 10,000 liquid compartments.
Give us a call when you have a challenge or opportunity and let us put our expertise to work for you!