Mill circuit pumps reduce operating costs
30 October 2018 | Web Article Number:
ENGINEERED for use in the most aggressive duties, Warman Mill Circuit pumps easily manage large size particles in highly abrasive slurries. These pumps are designed for the most severe slurry applications such as ball and SAG mill cyclone feed as well as water-flush crushing in mineral processing plants.
That’s according to Weir Minerals Africa, which showcased what it calls its flagship mill circuit pump, the Warman MCR450, at the recent Electra Mining Africa 2018 expo.
“Like all pumps in the Warman MCR range, this 13 ton slurry handling machine is designed to increase productivity and decrease downtime, compared to older generation and other pumps in the industry,” said Marnus Koorts, the company’s Product Manager, Slurry Pumps.
“Mill circuit applications are among the toughest in a minerals processing plant, and the Warman MCR pumps incorporate the latest in hypereutectic alloy and elastomer technology. This significantly extends the wear life of the pump in highly abrasive and corrosive slurries, reducing operational costs.”
He said the high resilience rubber wear liner enables the handling of coarse particles and ball scats with ease, while its lightweight design relative to other pumps in its category facilitates safer handling. It is also a lower cost than traditional heavy metal liners.
Different material combinations are available to suit specific site conditions.
The pump has a large diameter, low speed, high efficiency impeller. Koorts said this could be manufactured from a range of abrasion resistant alloys allowing the most appropriate material to be selected for the customer application. This will increase wear life and reduce operating costs when compared to other pumps in its category.
Reduced recirculation is achieved by the deep expelling vanes on the front of the high chrome alloy impellers. Expelling vane tip turbulence is minimised by the patented shroud feature that traps tip vortices and prevents localised scouring on the throatbush face. This, again, is intended to extend wear life and reduces maintenance.
The split outer casing on the pump provides structural integrity and high operating pressure capability, ease of maintenance and safety. This feature also allows internal liners to be fully worn before replacement.
Warman throatbushes feature pre-swirl vanes which offer better reliability and wear life. There is a patent pending on this innovative throatbush design which was developed to improve impeller eye wear life and reduce the wear caused by recirculation at the impeller-throatbush interface. This has been accomplished by a series of guide vanes in the pump inlet which induce a rotational velocity in the slurry.
An adjustable stuffing box allows for the centering of the stuffing box and lantern restrictor to the shaft sleeve. This increases packing life and decreases gland seal water consumption.
Another new design feature is the single-point gland adjustment which facilitates safe packing adjustment outside of the stuffing box guard while the pump is operating.