High-pressure water-powered valves and mining products and services company Hydro Power Equipment (HPE) is engineering a “robust” pressure-sustaining valve station to maintain a desired vertical column water level of 8 bar on the upper level of a shaft for a South African gold mining company, reports sales manager James Connear.

The mining client requires HPE’s valve solution to reduce the overall pumping volumes and lower the associated costs, by introducing clean fissure water from a neighbouring shaft into the mine’s service water system.

The client will be using water that is already being pumped out of their operation as make-up water, which will benefit HPE’s client in that it will significantly reduce pumping costs, he explains.

“This requires a correctly sized valve station, rated to 40 bar, capable of reducing the pressure from 17.7 bar at inlet, to almost zero at outlet, over a wide range of flow rates. Importantly, this must be done without cavitation despite the very high-pressure ratio,” elaborates Connear.

HPE valves are sized from 50 NB to 300 NB and are rated for working pressures of 250 bar (class 1 500). HPE also manufactures and installs a wide range of pressure-reducing valves (PRVs) and pressure-reducing stations (PRSs), which can be used to reduce the pressure of water that enters a water system at a mining operation to a desired pressure level for a specific environment, such as those required for downstream applications.

HPE’s PRS can be remotely monitored and controlled by means of electric actuation.

“We can incorporate our excess flow control valve. This valve acts as a mechanical fuse: when the flow rises above an adjustable setpoint, the excess flow control valve closes off in a slow controlled manner to prevent run-away conditions,” he says.

More Required from Valves

Mining valves and associated valve systems are transitioning from being passive mechanical components and are becoming increasingly “smart”, as manufacturers build in modern features such as real-time performance monitoring, data analytics tools for initiating energy-saving projects, as well as providing a solution for remote diagnostics and control, says Connear.

“Valves that help mines better control water usage and manage pressure surges can reduce resource wastage and support water licence compliance,” he says.

In addition to manufacturing and installing valves, HPE also specialises in the manufacture and installation of column protection systems, such as its surge anticipation valve (SAV) station, which serves to prevent pressure surges that are caused by pump tripping incidents resulting from electrical outages, without the need for battery uninterrupted power supply back-up solutions.

Connear says that SAV stations protect pump dewatering systems from high forces, pipe movement and pipe failure caused by pressure surges.