Reeling easy during large-scale dewatering

When some heavy-duty mine dewatering was required, a set of winder units emerged as a winning solution to Rio Tinto’s first agricultural project at the Marandoo mine in the Pilbara. Australian Mining reports.

The start of Rio Tinto’s agriculture project was instigated by a need to extend the life of an iron ore mine in the Pilbara, Western Australia by another 16 years.

The 17 million tonnes per year Marandoo operation on Rio Tinto’s Hamersley pastoral station is adjacent to Western Australia’s Karijini National Park.

This extension marked Rio Tinto’s first agriculture project, which attracted an investment of $US933 million (over $1.3 billion at February US-Australia exchange rates) in 2011.

Not only would the project extend the life of Marandoo to 2030, it would also sustain Rio Tinto’s annual capacity rate in the Pilbara.

Marandoo’s location below the water table added to the difficulty of the project – the mine extension was only possible if reserves were being developed adjacent to the groundwater table.

This project required the dewatering of the mine and water management strategy to deliver water to Marandoo’s mine operations and the Tom Price township 35 kilometres east of the mine.

The water would also be reinjected into the Southern Fortescue bore field lying within the Hamersley Station pastoral lease. As Rio Tinto’s dewatering supervisor at Marandoo searched for efficient ways to assist with the mine dewatering, a layflat hose system was procured from Crusader Hose in Melbourne.

This system of choice included 100- and 200-metre lengths of eight- and 12-inch Waterlord mine dewatering hose attached to custom-designed couplings, plus some shorter lengths as required, to assist with water pumping up the open cut mine to a tank once groundwater has reached the surface.

Crusader Hose managing director Francois Steverlynck, who has visited one of Rio Tinto’s sites, says deployment and retrieval of long lengths of layflat hose is not an easy task, especially when moving large volumes of water across the distance.

The previously used heavy six-metre poly pipe was rigid and had to be cut, welded and transported across Marandoo to connect to continually relocated bore outlets.

To address this time-consuming process, the Marandoo team procured a custom-designed Hamersley winder drive unit from Crusader Hose for the deployment and retrieval of the layflat hose as required.

The Hamersley 2.0 drive unit negates the need for an operator to come down from his or her forklift. It is automated with two hydraulic drive systems, so one can simply stay put and switch over the hydraulic control, and the lever will open itself up and drop the hose reel.

As the Hamersley 2.0 was attached to a telehandler or a forklift, the driver had to simply go to the area which required dewatering and deployed the hose at walking pace.

There was no plastic welding and lifting of six-metre lengths of polypipe required, as each reel of Hamersley 2.0 could carry up to 200 metres of the hose.

Steverlynck, who spoke to one of the dewatering supervisors, confirms the positive feedback on Hamersley’s performance. With Hamersley 2.0, one kilometre of hose could easily be connected by only two operators within three hours.

When necessary, heavy mining vehicles were also able to drive across the Waterlord hose, when it was without water and laid flat on the ground, without any damage.

This represented a considerable improvement in efficiency and safety compared to the polypipe option.

“Because we are a layflat hose specialist and manufacturer, we have developed our own reels and winders to manage and store our hoses,” Steverlynck tells Australian Mining.

“End-users’ feedback and requests push us to further develop and enhance custom-designed hose reels and hydraulic winder drive units that are specific to our customers’ needs.

“To date, we have over 10 models of hydraulic winders made for different applications.”

Crusader Hose also has a winder system called RD12, which is operated by manually unhooking the safety catches.

The heavy-duty hose winders boast a strong grip on the reel, proven by their ability to handle a hose up to 12 inches.

Both Hamersley 2.0 and RD12 are designed to retrofit with various telehandlers and forklifts.

When asked about Crusader Hose’s key to supporting efficient mining outputs, Steverlynck points to safety, durability and customisation underlying its product solutions.

The company is in the process of designing a truck-mounted winder system for use in a Western Australian diamond mine.

This article appears in the March 2019 issue of Australian Mining.

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