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Signature Sponsor
By Alan Hummer, Northeast Regional Manager and Lucas Jones, Director of Engineering, National Pump Company
January 23, 2026 - Vertical turbine pumps (VTPs) are an essential element of modern fluid systems, offering strong, reliable, and efficient pumping across many applications. They’re used everywhere, from the irrigation of farms and golf courses to supporting gold mines, municipal water supplies, cooling towers, mine dewatering, desalination plants, as well as a wide array of applications within the petroleum industry.
Recent implementations of these pump systems have included large aquifer projects, which can be designed to both extract and reinject water, thus supporting sustainable water management for drought-prone regions. Another example of unusual applications is the advanced turbine pumps used in a pumped storage hydropower (PSH) project in Australia, leveraging renewable energy for both water handling and power generation efficiencies.
From farms to municipal water systems to upstream, midstream, and downstream petroleum market applications, vertical turbine pumps power essential operations across countless industries.
Key Advantages of Vertical Turbine Pumps Several key features make VTPs an optimal choice across a broad range of applications and industries.
Solving Ground Water Extraction Problems Was Just the Beginning Vertical turbine pumps were originally developed for use in groundwater wells due to their simplicity of design, efficiency, and ability to lift water from significant depths without requiring priming.
To address the increasing demand for high-performance systems and the challenges of deep wells (exceeding 50 feet), engineers designed enclosed shaft systems. These designs encase the shaft and bearings in a protective, lubricant-filled tube (enclosing tube), keeping them isolated from the pumped fluid. Drip lines are also often used to lubricate bearings on deep well pumps. The use of enclosing tubes significantly improved durability and reliability, enabling pumps to perform effectively at significantly greater depths.
Groundwater applications are generally more standardized, as these systems are commonly designed to operate under relatively predictable conditions involving clean water extraction from wells or aquifers, in large volume and high pressure applications. These applications typically follow established specifications and require less customization.
Municipal and Industrial applications demanded larger pumps designed to handle a variety of liquids. The petroleum industry and industrial process applications often involve greater complexity, requiring custom engineering, specialized designs to meet detailed specifications, advanced materials, and rigorous testing to meet specific operational demands.
Modern VTPs, such as those offered by National Pump Company, a recognized market leader in vertical turbine pumps, can handle heads up to 2,500 feet, flow rates up to 20,000 gallons per minute, and power capacities as high as 2,000 horsepower
Ability to Solve NPSH Problems Lead The Way to Industrial Applications Vertical Turbine Pumps originally gained popularity as a solution to NPSH (Net Positive Suction Head) challenges, a critical issue in pump design and operation.
NPSH is a measure of the energy available at the eye of the pump impeller. NPSHA (Available NPSH) is the energy pushing liquid into the impeller, while NPSHR (Required NPSH) is determined through testing by the pump manufacturer and represents the minimum energy needed to prevent cavitation.
If NPSHA is not greater than NPSHR, the liquid can separate, creating “vapor bubbles” which is a boiling of the fluid, known as cavitation. This will occur at the impeller eye, which can severely impact pump performance and pump lifespan. In most systems, the only controllable factor influencing NPSHA is the vertical elevation, or suction head of the pumped fluid, above the pump's suction centerline.
For horizontal pumps, system designers have only two options to address NPSH issues: raising the liquid source level or placing the pump and motor in a pit. However, these solutions can be costly, pose safety risks, and introduce maintenance challenges, such as flooding or confined space hazards.
The advent of vertical turbine canned pumps provided system designers with a cost-effective, reliable option by allowing the pumping components to be mounted at a level below grade that meets the pump's NPSH requirement, while placing the motor and stuffing box above floor level. The use of an impeller specifically designed for low NPSH allows the length of the can and pump to be minimized while only marginally impacting overall pump efficiency, especially in multistage bowl assemblies.
The result is a very low life-cycle cost solution for difficult applications, such as condensate in power plants or propane and butane applications in midstream energy transfer. Vertical turbine pumps continue to be integrated into diverse and increasingly demanding applications. Advanced and highly specialized engineering solutions ensuring reliable, long-term performance are also attained by use of VTP’s.
The main components of VTPs include: a motor that powers the pump, a discharge head that redirects fluid flow, a vertical column pipe that transmits water and houses the pump shaft, and one or more impellers located within the pump bowl assembly at the base. These impellers generate the required force to efficiently push the fluid, eliminating the need for priming, as would be required for horizontal pumps.
VTPs Expand from Groundwater to Industrial Applications This proven capability made them a cost-effective solution that spurred their adoption in other sectors, particularly within the power and petroleum industries.
A key innovation was the development of the "can-style" VTP. By housing the pump within an outer casing, this design provided an economical solution for handling low-vapor-pressure liquids. It eliminated the need for expensive civil engineering work, such as elevating liquid sources or constructing flood-prone pits that were often necessary for horizontal pump installations.
As a result, VTPs have achieved widespread acceptance across numerous industries. They are now essential in municipal water supply, petroleum, desalination, snowmaking, cooling towers, and various other industrial processes.
Other Key Factors to Consider for Vertical Turbine Pumps When selecting a Vertical Turbine Pump, it’s essential to evaluate several critical factors in addition to NPSH that impact performance and reliability. These pumps require the expertise of manufacturers skilled in advanced engineering and precision quality manufacturing to ensure optimal functionality and long-term durability. Some of these factors include:
Vibration Managing vibration in VTPs is crucial for reliability, efficiency, and extending equipment lifespan. Excessive vibration can cause premature wear, component damage, and decreased performance. In one method to minimize vibration, manufacturers focus on separating the pump’s operating frequencies from the natural frequencies of its structure.
This is achieved through precise engineering, balanced rotors, robust shaft designs, and the use of high-quality materials. Proper balance and accurate coupling alignment are also critical for addressing harmonics and ensuring optimal performance.
Finite Element Analysis (FEA) is a powerful tool used to predict the natural frequencies of VTPs and their components, enabling engineers to identify and address potential resonance issues during the design phase. By simulating the structural behavior of the pump under various operating conditions, FEA ensures that critical elements are optimized to reduce vibration risks.
Computational Fluid Dynamics (CFD) is another advanced method used to analyze fluid flow within the pump, identifying turbulent zones and flow-induced forces which may contribute to vibration.
During installation, the pump must be correctly aligned, mounted securely, and placed on a ridged foundation to reduce resonance and vibration. Regular maintenance and monitoring further help detect and resolve vibration issues early, ensuring optimal performance. Advanced systems designed for applications requiring high reliability and performance utilize sensors to continuously monitor vibrations, enabling proactive, condition-based preventative maintenance.
Dry Running Dry running remains a significant challenge for VTPs, particularly in demanding applications such as hot water systems and scenarios with low NPSH. Dry running occurs when a pump operates without sufficient liquid, leading to inadequate lubrication and severe damage to internal components, including bearings.
Addressing this issue requires a combination of improved design practices and the integration of advanced materials to mitigate risks, enhance performance, and ensure long-term operational reliability.
Traditionally, carbon bearings were utilized in these critical conditions. However, their brittleness and handling difficulties posed significant challenges. Recent advancements in material science, including the development of advanced metal alloys and robust non-metallic materials, have significantly enhanced the capability of pumps to handle dry running scenarios and elevated temperatures. These material improvements ensure better durability, reduced wear, and increased reliability in extreme operating conditions.
Abrasives VTPs are increasingly being asked to handle abrasive fluids, a particular challenge due to the significant wear and tear abrasive particles can impose on pump components. Common abrasives encountered in VTP applications include sand, silt, and other particulate matter often present in well water or industrial processes. Several advancements in materials and design have been implemented to address these challenges effectively
From a design perspective, features such as enclosed line shaft configurations have proven highly effective. By enclosing the shaft within a lubricated tube, the design isolates the shaft from the pumped fluid, providing significant protection against abrasives. Modifications in the bowl assembly and other wetted components can be made to further enhance the pump's ability to handle abrasive fluids efficiently.
In terms of materials, the use of advanced bearing materials with superior resistance to abrasive wear has become a standard improvement. Additionally, the application of hard coatings or surface treatments on shafts and other key components helps minimize wear caused by abrasive particles. Elastomeric and Non-metallic bearings have also gained popularity, as they offer enhanced durability in abrasive environments compared to traditional metallic options.
Application-specific practices, including regular maintenance and monitoring, are critical in detecting and addressing abrasive wear before it leads to equipment failure. Continuous product development efforts are also underway, focusing on new alloys and advanced non-metallic materials capable of withstanding high-temperature and abrasive conditions. These ongoing innovations in materials and design ensure that VTPs remain reliable and efficient in demanding applications involving abrasive fluids.
VFDs Variable Frequency Drives (VFDs) are becoming more commonly used with VTPs due to their ability to enable variable speed operation rather than a fixed speed. This capability allows for more precise control of flow and pressure, improving energy efficiency and operational flexibility. Additionally, VFDs help optimize pump performance across varying operating conditions, reducing both energy consumption and wear.
However, the use of VFDs introduces challenges, particularly related to vibration and resonance. Operating pumps at variable speeds exposes them to a broader range of frequencies, increasing the likelihood of coinciding with the natural frequencies of the pump and motor assembly. This can result in unexpected vibration issues, which were commonly encountered in early VFD retrofits.
To mitigate these challenges, detailed structural and vibration analysis is critical during the pump design and selection process. Such analysis ensures that the pump's operating speed range avoids natural frequencies, reducing the risk of resonance and excessive vibration. Proper evaluation and design practices are essential to ensure reliable and efficient operation when integrating VFDs with vertical turbine pumps.
NSF Certification NSF certification is required for vertical turbine pumps used in municipal potable water applications, ensuring safety and quality. It verifies that materials and assembly processes do not introduce harmful substances, such as lead or toxic lubricants, into the water supply.
Maintaining NSF certification involves an ongoing process of rigorous annual material reviews and strict traceability for every pump component, ensuring that only approved, safe materials are used. Each assembly undergoes double-checks by quality teams prior to construction, with all lubricants and components verified for compliance with safety standards. Certified pumps use food-grade lubricants, follow strict assembly procedures to prevent contamination, and meet regulatory and public health standards, ensuring safe drinking water.
Municipal customers rely on NSF certification as proof that manufacturers meet rigorous safety and quality requirements. Pumps are available in various configurations, including oil-lubricated, water-lubricated, or product-lubricated options. Certified materials, such as stainless steel, aluminum bronze, or standard alloys, allow for customization to fit specific applications. Seal options for potable water applications include mechanical seals in split or single cartridge configurations or expanded PTFE yarn packing. The standard coating is Tnemec N-140 Pota-Pox Plus to provide long-lasting protection of the steel components.
Vertical Turbine Pumps – Advancing a Time-Tested Technology Vertical turbine pumps represent a well-established and reliable technology that has stood the test of time. Despite their maturity, these pumps continue to evolve to meet modern demands through advancements in materials, engineering, and design features. Working with a manufacturer that possesses deep expertise in pump design, hydraulic dynamics, harmonic analyses, and state-of-the-art testing facilities is crucial. Such expertise ensures optimal performance, efficiency, and the ability to tailor solutions for even the most challenging applications.
About the Authors
Alan Hummer, National Sales Manager, joined NPC in 2021 as a Regional Manager. Alan, like so many people in the pump industry, came into the industry after attending one of the country’s many maritime academies: Maine Maritime Class of ’85. His degree was in Marine Engineering with minors in engineering sciences and shipyard management. Working in pump sales in the New England area for over 30 years, Alan brings with him a wealth of experience, not just in pumps, but also in other aspects of technical sales and engineering. Alan remains ready to help out not only his sales team, but to step in and help valued customers when that extra attention is desired.
Lucas Jones is a mechanical engineer with 14 years of experience specializing in the design, analysis, and testing of complex mechanical systems for rotating machinery, automotive, and defense applications. He is currently Director of Engineering at National Pump Company. Lucas holds a B.S. in Mechanical Engineering from Washington State University, maintains ISO 9001:2015 internal auditor certification and Department of Defense security clearance, and enjoys hands-on troubleshooting and rebuilding machinery in his spare time. |
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