The new Warman DWU dewatering pump, designed in conjunction with Weir Minerals operations globally and manufactured in South Africa, has been engineered for harsh operating conditions typical of those encountered in Africa, according to the company. The “easy-to-maintain” pump is stated as producing efficiencies that are up to six points higher than other pumps in its class under certain conditions.
Weir Minerals states: “The innovative design of the Warman DWU pump offers customers a high head option encompassing the speeds for diesel and electrical driven applications, with heads exceeding 130 m.” The Warman DWU dewatering pump has been developed to enhance Weir Minerals Africa’s existing high lift dewatering pump range with a focus on high head mine dewatering, as well as any general dewatering applications.
Weir Minerals obtained registered design protection for the unique shape features of the DWU model pump. The DWU pump is able to handle dirty water with a specific gravity of 1.05, and has a casing that is pressure rated at 7,000 kPa for series pumping, if required. The range is made up of four pump frames – DWU 200, 150, 125 and 75. At maximum operating speed, the DWU 200 pump can achieve a head of 115 m at best efficiency point, with smaller units able to achieve up to 140 m on a single pump. The one-piece frame concept aids the correct alignment of bearings, seals and impeller.
Weir Minerals’ R&D engineers have used a double volute casing design and impeller balance holes to reduce the radial and axial hydraulic loads. By harnessing the new Warman WBH pump’s mechanical end design, customers have about 90% component interchangeability between the WBH pump and the DWU pump, enabling them to reduce their spare parts stockholding when operating both types of pumps. The mechanical end of the WBH pump is available in either grease or oil lubricated options, offering flexibility in configuration, while the rotatable casing also provides flexibility in configuration and installation.
The DWU pump incorporates the WBH pump’s bearing housing and its large capacity bearings are capable of withstanding high loads ensuring long bearing life. The SGI (spheroidal graphite iron) casing can tolerate pressures up to 70 bar with five pumps in series.