Dewatering Solutions Answer Core Challenges

Upgraded pumps and software offer cost savings, and improve reliability and ease of use

by jesse morton technical writer

The constancy of flooding and water ingress at surface mine sites generates unabated demand for efficient and reliable dewatering solutions, which in turn prompts suppliers to regularly update and improve their flagship offerings. For example, within the last few months alone, Schurco Slurry began developing a new bearing seal design for its pumps that is expected to improve already top-notch performance. Franklin Electric released a modular pump-and-motor package that is reportedly super-easy to design, order, assemble, deploy, maintain and move. And Applied Flow Technology released an upgrade to Fathom, the proven software solution used by engineers to model and virtually trial pump and pipe systems. Fathom 12 includes tools and features that expedite model creation and streamline the comparative analysis process.

These developments show that the most successful suppliers in the market are the ones that seek first to answer the core needs of new and existing customers. Going by recent headlines, today those needs are lower costs, optimal availability and general ease of use.

Superior Reliability, Lower Operating Speeds

Schurco Slurry reported the V-Series pumps offer a low upfront purchase price, superior reliability, lower operating speeds, and the ability to operate in run-dry conditions.

The pumps “are ideal for a variety of sump applications,” the company said. They can also be readily applied on floating dewatering applications as well as floating pump platforms or barges.

V-Series pumps feature a complete cantilever design with no submerged bearings or shaft seal, and are available in numerous materials for any slurry environment, an engineer at the OEM said.

“Our V-Series pumps with their cantilever design are the perfect fit for sumps and pits because they are not only less expensive than submersible pumps, but also are more reliable,” said Oliver Nobels, application engineer, Schurco Slurry. “There are no submerged bearings or shaft seal, and the pump can be fitted in numerous material options for any slurry environment.”

V-Series units have discharge diameters of 1.5 to 10 in., heads through 160 ft, and flow rates through 6,000 gallons per minute (gpm).

The pumps feature unique double-suction impellers; a maintenance-friendly bearing assembly that has heavy-duty roller bearings, robust housings, an oversized shaft diameter; and metal- or rubber-coated pump columns and discharge pipes. Recessed impeller designs for large particle applications and a suction agitator are optional.

“Our units utilize more robust wet-end components that offer higher mass per part, extending pump life in abrasive slurry environments,” Nobels said. “Our units also have no lower bearing or lower seal housing.”

Further, the pumps run at a lower RPM. “All operators know that the lower operating RPM means longer life cycle,” he said.

The V-Series pumps are not affected in a dry-running situation, Nobels said. “If a sump runs dry, they operate in a ‘snore mode’ with no negative affect, giving plants a forgiveness factor when there is an upset in the process.”

The innovative design and the widely configurable range help customers cut costs in multiple ways.

There are “very few parts to install, and, with the simple design, these pumps have the lowest maintenance requirement of all Schurco pumps,” Nobels said.

The pumps have excellent wear-life properties, further reducing operating costs, the company said. “These vertical slurry pumps can be fully elastomer lined or hard metal fitted.”

Adoption and maintenance of the units is backed by the OEM’s support services. “When working with Schurco, customers get application specialists to help specify optimal solutions,” Nobels said. “The needed inventory and parts will be on shelf.”

Currently, “Schurco engineers are in the process of developing a new bearing seal design that will drastically increase bearing assembly reliability,” said Nick Schur, president, Schurco Slurry. “The one complaint from customers is that, when their sump floods, the lower bearing can fail due to product ingress,” he said. “The new design is based in collaboration with a well-known U.S.-based sealing company, and it will protect the lower bearing, thus increasing bearing life when sump levels flood the pump.”

Such customer-feedback-driven research and development shows the company’s “goal is not just to be an equipment supplier, but a partner to our customers,” Schur said.

“We want to help them develop and implement solutions that will help lower their production costs,” he said. “This will help ensure not only their success as a company and employer, but also our success.”

Proven Performance, Streamlined Ordering

Franklin Electric’s Pioneer Pump released the ElectricPAK, a product line of modular electric pump packages that can be rapidly designed and assembled and that offer maintenance cost savings. The solution is “extremely popular due to the ease of configuration” and the robust design, said Mario DeSimone, product manager, large centrifugal pumps, Franklin Electric.

“For coal mines with electricity available to power the pump, an electric pump package can be significantly less expensive to operate than a diesel-powered package,” he said. “There are also safety benefits inherent to electric-powered pumps, such as fewer pinch points, lower operating temperatures, and less risk of a fuel or diesel exhaust fluid spill.”

The platforms can be configured for various pump-and-motor combinations. Discharge diameters on the pumps range from 3 to 12 in. The motors range in power from 7.5 to 350 hp.

“Pioneer Pump offers an extensive range of totally enclosed fan-cooled premium-efficiency, severe-duty-rated motor options, which allows users to select the most efficient pump for the duty point,” DeSimone said. “Package design options include high-performance pumps that provide better flow, higher head, and greater efficiency.”

Packages can be quickly and easily configured using Franklin Electric’s online FE Select tool. They are “quicker to manufacture and ship because of the modular design, and are more robust than traditional electric pump packages,” DeSimone said.

The FE Select tool allows a user to rapidly access and act upon the information it generates. “Select, configure and quote a complete ElectricPAK in minutes, anytime and from any web-enabled device using FE Select,” DeSimone said. It also quickly renders a drawing.

“With pre-determined product selection options, a modular package design provides the ability to save time on the front end of the selection process without sacrificing the flexibility and efficiency of an engineered product,” he said.

“The modular design is built using standard, interchangeable parts, delivering upfront time savings for the system designer,” DeSimone said. “Custom packages often take longer to build and are more complicated to engineer.”

The heavy-duty motor stool design eliminates the possibility of the pump and motor coming out of alignment, eliminating the downtime required for a laser alignment.

“The motor stool is engineered to precise tolerances to ensure that the coupling remains aligned and protected,” DeSimone said.

In mining applications, a misaligned pump and motor commonly causes malfunction and downtime. The misalignment can occur when a package is not assembled correctly, when it is hit by mobile equipment, or when it is being moved from place to place at the mine.

“Mines are often rugged environments, and pump packages can be at risk of being hit by trucks and other pieces of equipment,” DeSimone said. “Pump packages used in mines are also frequently moved around the job site and have pipe and hose exerting loads on the pump and base.”

A pump-motor misalignment “can lead to long-term vibration-related maintenance issues, including seal failures, unexpected power losses, and, in worst-case-scenario situations, a broken shaft,” he said. “This makes a strong pump-motor connection even more important since the vibration from movement around the job site can cause misalignment, which could result in costly downtime.”

The rigid motor stool design of an ElectricPAK package eliminates any alignment concerns that result from everyday use of the unit itself or the environment where it is located, he said.

“ElectricPAK units can be moved and transported freely without the need to perform a re-alignment and are designed specifically with heavy-duty, suction lift applications in mind,” DeSimone said. “This means that the pump package can be delivered to a mine and start up right away.”

It also means the package can be used in both permanent and temporary installations across the mine “since grouting for fixed installations is not required.”

The modular design of the package allows for relatively quick disassembly and maintenance, reducing the total cost of ownership.

Other benefits of the modular design include a shortened lead time and improved product availability.

Every Pioneer ElectricPAK can be configured to include a Pioneer Prime system, which offers several benefits.

“The Pioneer Prime hydraulic design maximizes lift capability and offers both quick initial priming and continuous, unattended reprime under auto stop-start conditions,” DeSimone said. “It gives a faster priming time compared to compressor-driven priming systems.”

Pioneer Prime requires no water to prime the pump, and prevents product carryover. “It enables unassisted dry priming,” he said. And it helps the package “achieve higher performance and increased energy efficiency.”

The ElectricPAK line allows customers that are accustomed to diesel packages and, at the same time compelled by new sustainability guidelines, to quickly and easily trial an electric package. “They are a great introduction to electric-driven pump packages,” DeSimone said.

“It is available with Franklin Electric’s Cerus X-Drive variable-frequency drive, so the pump can be run at a variety of duty points across the pump curve, like a diesel package,” he said. “An integrated drive, mounted and wired at the factory, saves time, enhances safety, and ensures a long product life, in addition to total system integration.”

The new release is expected to grow the supplier’s business in the coal space. “Franklin Electric’s mission is to be a vital global leader in the manufacturing and distribution of products and systems, focused on the movement and management of water,” DeSimone said.

“Our vision is to be an indispensable partner to our customers by consistently delivering high-quality, innovative products that offer exceptional performance and improved efficiencies,” he said. “The ElectricPAK is an industry-leading product that offers owners and operators a long-term, sustainable solution that makes Franklin Electric an indispensable partner to our customers through the Pioneer Pump brand.”

Streamlined Model Specification, Analysis

Applied Flow Technology released AFT Fathom 12, the latest iteration of its flagship fluid dynamic modeling software solution, in Q4 2021. The updated version has new features and tools to streamline the workflow for model specification and analysis, an engineer at AFT said.

“With the new version, we build upon our foundational strengths to refine the features and processes our users are accustomed to, allowing users to easily compile their model information into libraries and visualize the results of their system with multi-scenario graphing,” said Nick Vastine, business applications engineer, AFT.

AFT Fathom 12 features improvements to the modeling process, improved organization of warnings, and easier use of the library and database.

The software solution is designed for use by engineers to, among other things, calculate pressure drop and pipe flow distribution in liquid and low-velocity gas piping and ducting systems.

“Engineers can build a representation of their system’s pipes, pumps, components, and branches to ensure their equipment is properly sized and will operate as expected,” Vastine said. “This model can then be tuned and experimented on to reveal efficiency improvements or consider a range of potential operating conditions.”

For example, the solution uses a tool called Scenario Manager that allows users “to explore unique scenarios like changes in operating conditions, evaluate resizing equipment, or follow their curiosity to discover better designs,” he said.

“All of these scenarios are built within a single file, making quick iterative engineering or correcting mis-input as painless as possible,” Vastine said. “This flexibility and other features that speed up comparative analysis are only a few of the ways AFT Fathom has remained competitive for nearly 30 years.”

AFT Fathom can help an engineer design, virtually test, and troubleshoot a system for dewatering at a mine site.

“It is almost a constant battle to keep water out of a surface mine, either from the natural water table, rivers, streams, or storm events,” he said.

“AFT Fathom enables engineers to find the most efficient way to transport this water, avoiding safety hazards or other disruptions to mine production,” Vastine said. “Engineers could use our software to size equipment, configure existing components like skid-mounted pumps, and consider changes in the supply condition and its impact to system performance.”

The solution helps an engineer design a hydraulic system that can constantly fluctuate supply or demand. It helps ensure “that a single system can handle each of the extremes of operation, avoiding flood risk and it’s devastating effects,” Vastine said. “AFT Fathom can confirm the sizing of pumps and piping for these extremes, but also considers their operating point to maximize efficiency and reliability in each case.”

For surface coal dewatering applications, models generated in AFT Fathom “can ensure the constantly changing operating conditions don’t cause downtime from undersized or poorly designed systems, at the same time ensuring the operation of your pumps is as efficient as possible,” he said. “By creating a model of your system, it also enables an engineer to experiment with set-ups or operating cases within a computer rather than experiment in the field, ideally settling on an optimized solution before changing anything that could disrupt production.”

Historically, hydraulic engineers have used the software to troubleshoot hypothetical challenges and test preemptive measures. For example, an engineering contractor in Australia used it to model and trial a system involving four skid-mounted parallel pump sets to pump 7,600 gpm over more than 2.7 miles up a 1,300 ft elevation.

“Due to the narrow piping and significant elevation gain, NPSH and cavitation were major concerns during design,” Vastine said. “Mounted to skids, the contractor had the flexibility to rearrange the pumps and adjust their speed to meet suction and discharge pressure requirements.”

As the mine further developed, the engineering contractor used AFT Fathom to study the benefits and effects of adding more skids to overcome the increased mine depth.

The contractor “credited the ease to evaluate what-if scenarios for optimizing the solution for cost, and thought the graphics generated in the applications clearly communicated the design’s compliance to requirements,” Vastine said.

AFT Fathom was initially released in 1994 as the first drag-and-drop interface in a hydraulic design tool. “Since then, AFT Fathom has accumulated users in over 80 countries via our sales network of 42 regional channel partners,” he said. “Nearly 30 years later, AFT Fathom 12 was released in November 2021, further building upon the foundations established decades before.”

Ultimately, the software and module are purpose-designed for engineers. New or prospective users “should have a foundation in the basics of fluid flow analysis before building models of their systems,” he said.

AFT Fathom advances the company’s mission “to empower engineers to intelligently design fluid transfer systems with innovative tools, education, and service,” he said. “Our tools, like AFT Fathom, ensure engineers can design their system to be safe, reliable, and efficient.”