MechChem Africa November-December 2024

⎪ Water, wastewater and pumping solutions ⎪

short term emergency solutions or a perma nent installation.

Submersible dewatering solutions Pointing to the range of range of Xylem Flygt submersible dewatering pumps, Höll says that these now come in a 2600 slimline range, which goes up to 18 kW, as well as well as the traditional 2800 series side discharge sub mersibles. “The slimline range discharged in the vertical plane from the top with the suction below. It is designed for dropping into a flood ed area such as mine shaft and left to dewater the area. They have an enormous number of uses such as draining flooded stormwater through manholes, but the slimline range is particularly suited to the constrained spaces we find in mining applications,” says Höll, adding that side-discharge Flygt dewatering pumps in the 2800 series tend to have a lower centre of gravity and a heavier base, so they are less likely to topple. The two ranges use exactly the same hy draulics, though, with the same motors and interchangeable impellers. And like all Flygt submersible dewatering pumps, they come with an IP68 rating, which means they're fully sealed and protected against water and particulate ingress. Single plug mechanical seals are now used between the impeller on the wet-end of the pump and the motor chamber, and the stator of the motor is surrounded by a water-jacket to allow the water being pumped is be used for cooling. “It is not necessary to have the pump fully submerged for adequate cooling, though, and even if the pumps run dry for an extended period, the thermal protection module that is standard with all of these pumps will trip automatically – and once it cools down, it will restart again,” he points out, adding that the pumps are also fitted with an air release valves to expel any heat trapped in the casing, which aids in keeping the motor cool when dry-running occurs. The position of the power cabling coming down from the surface has also been shifted on the new versions of these pumps to sit just behind the discharge pipe. “This is a just as a bit of additional safety to prevent any damage to the cable should the pump topple over,” Höll adds. Depending on the head and flow require ments of the applications, Xylem can offer SH (super high head), HT (high head) and MT (medium head) versions of both the slimline 2600 and side discharge 2800 submersibles – and B (wear resistant) and K (open) impel lers are also available. And to suite the most robust applications, Xylem Hard-Iron™ im pellers (60 HRC) and suction covers reduce wear and increases uptime, while the unique closed impeller design and suction cover with Dura-Spin™ grooves work together to sweep

Left: With the ability to interchange between the 2-bladed BD150T impeller for solids handling and the more efficient 3-bladed BD150C impeller for clean water applications, the BD150 offers two pump application options. Right: The BD150 includes fully automatic dry priming with 8.5 m of suction lift. Two self-priming options are available, including a vacuum pump option or a venturi priming system driven off an air compressor.

abrasive particles away from the impeller neck. In addition, a patented design called Spin-Out™ extends service life by expelling abrasive particles away from the seal.

“With mines going deeper and deeper, dewa tering needs are becoming ever more chal lenging. Multistage pumps on the surface can sometimes handle these depths, but they are mostly designed for clear water and they tend to experience suction lift limitations. Being submersible, the new multi-stage Flygt 2450 can sit below the water level and pump water up to an underground reservoir hundreds of meters above it. From there, an other multistage submersible can pump the water another 300 m, and so on,” he explains. “Xylem brands are well-known for their performance, quality and reliability. If you want your pumps to run at optimal efficiency, we offer the guarantees of a global OEM, along with the very best aftersales support. “When it comes to dewatering, we have the products, the expertise and people on the ground to make a difference,” concludes Jonathan Höll. www.xylem.com/en-za

Xylem’s new 2450 multistage pump

Also very new to Xylem Africa and not yet launched in the Africa region – a full launch is planned for April or May next year – is the new three-stage Flygt 2450, a high-head submersible that is ideal for underground mine dewatering. “We have long had a two stage version of this pump, the 2400, but we have now extended the performance of this range by adding and additional stage, which takes the pressure head capability up another notch,” he explains. The extra stage and the bigger motor pushes the total pressure rating up by a further 10 bar compared to our two-stage version, which takes the 2450 pump to 300 m of lift.

Pointing to the range of range of Xylem Flygt submersible dewatering pumps, Höll says that these now come in a 2600 slimline range, which goes up to 18 kW, as well as well as the traditional 2800 series side discharge submersibles.

November-December 2024 • MechChem Africa ¦ 13