Tag Archives: slurry

Weir releases new gate valve as it advances Terraflowing, ToolTek solutions

Weir Minerals has released a new Isogate® WR knife gate valve to reduce cycling discharge while improving wear life.

The lightweight, long-lasting Isogate WR knife gate valve offers miners and aggregates operators alike a step change in valve performance, according to Weir Minerals.

The release came on the same week Weir Group announced its 2020 financial results, which saw the company report revenue and adjusted operating profit of £1.97 billion ($2.73 billion) and £305 million from continuing operations, respectively. These figures were down 4% and 3%, respectively, from 2019 totals.

On the new valve, Weir said: “Incorporating the latest advances in design and materials technology from Weir Minerals’ expert engineers, the range of Isogate WR knife gate valves are more reliable, while producing minimal fluid discharge and weighing considerably less than equivalent mining valves.”

John Abbott, Global Product Manager – Valves & Tailings, said: “Drawing on decades of wear analysis, we’ve optimised the Isogate WR knife gate valve’s body design, by reinforcing the areas subjected to the harshest wear and pressure. At the same time, we have reduced the weight elsewhere to produce a robust, long-lasting mining valve that’s significantly lighter than comparable products.

“The weight reduction can be especially significant in situations where a number of valves are used on a specific installation, such as in a hydrocyclone cluster, or where lightweight piping systems are used.”

The gate has also been redesigned, with stronger materials resulting in a thinner gate that can still withstand the pressure of mining slurries. This combines with the valve’s unique gate guide that, Weir says, reduces deflection by ensuring smooth gate movement and less strain on the sleeve elastomer during blade transition.

The Isogate WR knife gate valve uses Weir Minerals’ new Isogate WSL sleeve, which comes with proprietary Linard® HD 60 silica-reinforced natural rubber to solve the three most common problems with sleeved knife gate valves: leakage during cycling, tearing and load distribution ring (LDR) failure due to corrosion and erosion, the company explained.

Leveraging the Linard HD 60 rubber’s high resilience against cut, tear and abrasive wear to improve wear life, the new Isogate WSL sleeve fully encloses the LDR to prevent corrosion. By allowing the rubber to move with the blade cycles, the design reduces the chance of tearing while reducing slurry discharge by up to 75%, according to Weir.

The Isogate WSL sleeve can also be used in existing Isogate WS knife gate valves, improving wear life and decreasing discharge on cycling.

Abbott added: “When designing the Isogate WR knife gate valve, we focused on features that improve the everyday experience of working with our valves. This includes important things like improved grease distribution and improved body flushing when used on high solids concentration applications.

“In-depth finite element analysis enables us to ensure the product’s integrity, while making it lightweight. There are also a lot of smaller features to make life easier, such as a larger grease reservoir, ISO mount standardisation and an external visual indicator for the valve’s status.”

Other notable developments from Weir Group’s 2020 financial results included the first order for ESCO’s ToolTek™ system.

This collaborative effort with key mining customers provides enhanced safety for maintenance personnel during the replacement of worn Nemisys® points and adapters, according to ESCO. It features a hydraulic crane mounted tool that is remotely operated, well out of harm’s way during the replacement of worn components. New parts are pre-staged on racks  positioned on the flatbed truck outfitted with the hydraulic crane. The truck also features a recycle bin for safer disposal of worn parts.

Alongside this, Weir said in 2020 it installed the first pilot Terraflowing® plant at a customer’s mine site designed to cost-effectively reduce water in tailings, enabling this waste product to be safely stored or repurposed.

Terraflowing incorporates a two-stage cyclone dewatering process followed by centrifugation of the final stage of cycloning overflow. In the process, three dewatered tailings streams are produced: a primary cyclone underflow, a secondary cyclone underflow and a centrifuge pulp. These three streams can be combined or used in different configurations depending on the end use of the tailings stream, according to Weir Minerals.

This three-stage system offers the flexibility to make provision for variations in mineralogy and particle size distribution as well as the opportunity to recover ‘tailings as a resource’, it added.

Weir’s Warman MCR pump more than doubles wear life at Agnico’s LaRonde mine

The superiority of genuine Warman® pumps and parts has been proven in a trial comparing the performance of a Warman MCR® 250 pump with a Warman AH® pump fitted with non-genuine spare parts at Agnico Eagle Mines’ LaRonde gold mine in Quebec, Canada, Weir Minerals says.

The mine had been using two Warman AH 12/10 slurry pumps to manage its SAG mill discharge since operations commenced in 1988. While these pumps were the latest technology at the time, the very coarse slurry was causing the pumps to wear out after just 1,600 hours, according to Weir.

“When a replicator proposed a trial of non-OEM pump liners and parts instead of our genuine Warman parts, they promised to double the wear life of the existing pump components,” Mike Swintak, Regional Senior Product Manager for Weir Minerals, said. “Our engineers investigated the root cause of the wear life problems experienced and decided a Warman MCR pump would achieve much better results compared to the AH pump with non-OEM parts.”

Instead of doubling it, the other manufacturer’s liners and impellers decreased the pump’s wear life by 300 hours, wearing out after just 1,300 hours. In addition to requiring six rebuilds per year, the non-genuine parts interrupted production due to discovery of premature cracks in the liner, Weir said.

Meanwhile, the Warman MCR 250 pump achieved 3,000 hours of continuous operation, requiring only three rebuilds and lowered spare parts costs alone by 36%, or $70,000 per year.

Swintak said: “The fantastic results achieved at LaRonde weren’t just due to the superior wear resistance offered by the pump’s Ultrachrome A05 wear material and superior hydraulic design of the MCR pump. Our engineers worked closely with Agnico Eagle operators to remove problems throughout the circuit contributing to the low wear life being achieved, such as revising their pump box level control procedures and monitoring system to ensure a constant level of 50-75%.”

Tsurumi ups the slurry pumping ante with GPN 837

Tsurumi has released a new heavy-duty slurry pump that, it says, almost doubles the output of its predecessor pumps.

Coming with a water output of up to 9,000 litres/min, the new GPN 837 is the top model in the series, topping the GPN 622.

“However, ‘water’ can hardly be taken literally: declared as a “heavy sand pump”, the GPN 837 is intended for use wherever considerable amounts of solid matter are involved,” the company says.

This includes gravel pits or where sand, sludge, slurry and preferably also bentonite are involved. Mining is also a target market.

With these applications in mind, the engineers designed the pump with a solid construction. At 150 litres/s, hard rock up to 30 mm in size can pass through the pump with ease. Also, the agitator at the suction opening mixes mud and water so that the solution becomes more fluid.

The pump comes with a dry weight of 815 kg, a height of roughly one meter, is driven by an electric motor with 37 kW (400 V) and can pump vertically up to 24 m. When submerged, it is pressure-resistant to a depth of 30 m, the company says.

The water is diverted in a spiral around the pump – a design to counter the high abrasive effect of the pumped medium – while the impeller and suction plate is made of chrome cast iron, the housing of grey cast iron GG 20. For critical elements such as the double inside mechanical seal, the manufacturer uses silicon carbide. Tsurumi´s oil lifter, which lubricates the pump shaft in any position reliably by centrifugal force, is also a feature.

Trelleborg expansion barrels keep slurry moving at Canada oil sands mine

Trelleborg is helping improve uptime at a major oil sands mine in Alberta, Canada, through the delivery of rubber-lined expansion barrels.

Due to the size of the operation, oil sands slurry and sediments must travel long distances in the mine’s pipeline system. The mine, therefore, chose Trelleborg’s expansion barrels, which enable the thermal expansion and compression of pipelines, to facilitate extended periods of travel in extreme temperatures at the mine.

This removed the mine’s need for frequent maintenance and consequent downtime caused by extensive wear on the barrel, Trelleborg said.

“The expansion barrels, which were tested over a four-year period at the mine, are flexible in all directions, so they can compensate for the thermal expansion and lateral deflection in a pipe system,” the company said. This enabled the pumps, which circulate the slurry throughout the system, to be protected against load forces and allow for a safe expansion and compression.

Richard Hepworth, President of Trelleborg’s marine and infrastructure operation, which delivered the solution, said: “Testing proved that slurry was able to travel for 24,000 hours in the pipe without maintenance, equating to approximately three years, as opposed to around 4,000 hours, which non-expanding barrels often provide.

“With temperatures across certain parts of our mine reaching as low as -46°C, downtime can compromise the safety of our people during maintenance.”

He added: “With our in-house expertise and mining knowledge, we knew we could supply equipment to meet the demands of the mine’s environmental and business challenges, while providing a solution that can compensate for two or three expansion joints and allow for easy mounting and inspecting.”

The configuration of Trelleborg’s barrel, which can successfully operate in temperatures between -46°C and 90°C – and has an expansion/compression range of 910 mm – was successfully patented in Canada in 2012. The barrel also provides an installation hydraulic ram as a feature for simpler maintenance and rotation.

GIW launches the largest slurry pump in the Canada oil sands

GIW Industries has launched what it says is the largest and heaviest pump available in the mining industry, targeting heavy-duty slurry transport applications in the Canada oil sands.

The GIW® TBC-92 slurry pump is named for its 92 in (2.34 m) impeller and is the latest in a line of powerful high-pressure pumps offered by GIW, the company said.

“The installation of the TBC-92 marks an important milestone: GIW now has pumps in service at all operating Canadian oil sands hydrotransport applications,” GIW said. “The TBC-92 is designed to tackle heavy-duty slurry transport while providing a low total cost of ownership. Minimal labour and maintenance time help to maximise production and profit.”

According to GIW Business Development Manager, Mollie Timmerman, this latest pump incorporates lessons learned over the years from operating in the oil sands, and features GIW’s latest hydraulic and wear technologies.

“Because this is the heaviest TBC pump we have ever designed, particular attention was given to maintainability, as well as material selection and construction of the pressure-containing components,” she said.

The TBC-92 combines the best elements of the products that preceded it, according to the company. This includes many elements from the TBC-84, also known as the ‘Super Pump’, and added features from GIW’s MDX product line – used in heavy-duty mining circuits throughout the world of hard-rock mining such as the First Quantum-owned Cobre Panama mine.

“The client needed a higher-capacity pump than was currently available on the market; the TBC-92 pump is the best solution for maximised production,” Timmerman said.

In total, the TBC-92 weighs about 209,000 lb (94.8 t), with a casing that weighs 34,000 lb (15.4 t) by itself. For ease of maintenance, customers receive custom lifting devices to facilitate safe removal and installation of wear components, GIW said. The pump also features a long-lasting suction liner that can be adjusted without needing to shut the pump down.

After the pump is installed, dedicated site account managers are on call to work through the start-up process, according to GIW, while local services and spare parts supply will be based out of GIW’s Fort McMurray Service Centre, located close by to the oil sands operations.

FLSmidth seals the deal with Krebs Technequip TGW knife gate slurry valves

FLSmidth says its Krebs® Technequip™ TGW series of wafer-style knife gate slurry valves have proven themselves across the globe.

The valves are designed specifically for the harsh and abrasive slurries encountered in the mineral processing and power industries, with applications ranging from cement, sand and gravel to coal, phosphate, ash and alumina.

They are designed as a space saving option for heavy-duty applications, according to the company. The long-lasting replaceable elastomer sleeves offer a sealing solution that uses the latest technology, with the valve’s operation based on its full port design, FLSmidth said. This allows the gate to be fully isolated by the sleeves from the process in the open position.

“As the gate closes, it pushes between the two sleeves, discharging a small amount of material out of the bottom of the valve,” FLSmidth said. “This prevents material build-up in the seat area ensuring full gate closure, as well as preventing damage to the gate. When the gate is in the open or closed position, there is a 100% bi-directional bubbletight seal and zero downstream leakage.”

To ensure long life, all valves are supplied with dust boots – or ‘bellows’ – as a standard feature, protecting valve stems and actuators. Hardware such as nuts, bolts, and washers, meanwhile, are zinc-plated to protect against corrosion. Each component is also individually epoxy-painted before assembly.

Several actuation options are available, including pneumatic, hydraulic, electric and bevel-gear actuators, as well as manual hand-wheel operators, the company said.

The choice of materials is vital to the valves’ performance, reliability and lifespan, according to FLSmidth. “Sleeves are constructed of dense moulded elastomer, complete with an integral stiffener ring moulded into the sleeve. They are also available in a range of different materials to suit the application,” the company said. The valve housing is ASTM A536 cast ductile coated for corrosion resistance, while the upper cavity is pre-lubricated with a silicone-based grease, to improve actuation and decrease wear.

Founded in Toronto, Canada, in 1957, Technequip was acquired by FLSmidth in 1993 and integrated into the company in 2007. With installations across the globe, the slurry valves have proven themselves worldwide with features like the fluorocarbon gate coating for reduced friction during actuation, the high strength stainless steel gate clevis and two-coat epoxy paint. The valves also contain no packing gland, as this can jam the gate, and have machined gate guides so no spacer bars are required. Various accessories are available, including solenoids, limit switches and junction boxes.

Brain Industries devises versatile self-filling tanker for sludge, slurry clean up

An underground coal mine in Australia is piloting the use of a self-filling tank to help clean up sludge and slurries.

The mine in question is Anglo American’s Moranbah North coal operation in Queensland and the product is a new hydraulics-fitted version of Brain Industries’ self-filling tanker, Brain said.

Brain’s Managing Director, Gillian Summers, said the tanker is an advancement on Brain’s air-driven model which enables vacuum recovery, haulage and dumping of heavily solids laden slurries and sludges containing lumps up to 150 mm in size.

Summers said the new 6 cu m tanker has been produced in response to calls from the underground mining industry for more versatility and can be run from any LHD.

She said powerful jet pumps mean Brain’s self-filling tankers vacuum-load continuously to achieve high loading rates. Also, it is constructed aluminium free to comply with mining regulations.

“While the new hydraulics version was produced for underground mines, our self-filling tankers are also suited to applications in hard-rock mining, tunnelling and contract cleaning services,” she said.

“With no moving parts in contact with the material, continuous loading of large lump solids, including waxy, fibrous and abrasive materials, is possible without detriment to the pump.”

Loading stops automatically at a high level when handling wet materials, according to Brain. Excess water can be drained from the tailgate valves to allow top-up of load, maximising hauled solids.

Summers said the tanker is not only easy to use but easy to empty, with the use of a 250-mm diameter dump hatch or full-sized rear door.

Existing customers can also benefit from this new technology, with the company’s line of air driven self-filling tankers able to be retrofitted with hydraulics.

Brain’s self-filling tankers can be skid-mounted or trailer-mounted. The skid-mounted unit is made to be transported on a flatbed trailer or truck using the side-accessed forklift sockets, with the multi-purpose vehicle unit also able to be transported above ground in this way. The trailer-mounted self-filling tanker has a rocker arm, load sharing wheels with oil-filled hubs and solid tyres, Brain added.

The fine print in FLSmidth’s REFLUX Classifier technology

FLSmidth has looked to spell out to the mining industry the benefits of its REFLUX™ Classifier (RC™) technology.

The RC is a slurry-based gravity separator designed specifically to upgrade fine minerals generally finer than 2 mm, the company says.

“The key design element is a system of lamella plates or inclined channels and the internal overflow launders. These are contained within the Lamella Settler – the top portion of the RC. The other two main components are an Autogenous Dense Medium Separator underneath the lamella chamber, and a Fluidised Bed Separator beneath that.”

Material from the process plant enters through the slurry inlet and passes over an internal over-size protection screen, removing any tramp or debris that may cause damage to the ceramic underflow valve.

Large, high-density solids quickly sink and settle in the mixing chamber in the middle section of the classifier, forming a fluidised bed of dense material. This bed is created by a series of water jets at the base of the mixing chamber and rejects any trapped lighter particles.

“Lighter and finer particles rise in the RC, through the autogenous zone to the lamella section,” FLSmidth says. “The autogenous section is created by fine suspended solids, and this zone helps convey lighter particles to the lamella section.”

This upper section contains the crucial sloping lamella channels, typically placed 6mm apart – although this distance can be reduced for finer materials. Low density particles rise up through these channels, driven by the upward water flow from the feed. The narrow sloping channels cause a parabolic flow pattern where the flow is fastest midway between the channel walls, the company says.

“The lightest particles are carried by the faster flow before they can settle and they overflow at the top of the channel. They fall into internal launders and are discharged from the RC. The higher density particles tend to slide back along the topside of the lamella channel, where the flow is slower. These particles slide down the slope, back to form the autogenous dense media zone,” FLSmidth says.

Pressure probes monitor the bed density and automatically control the underflow valve to optimise the bed level and density. The fluidised bed keeps particles in suspension and rejects the lighter material up out of the bed, while the denser particles sink and flow out through the underflow valve.

“The valve’s four-link system moves the plug vertically, which reduces wear and provides protection against splashing,” the company says.

In a recent innovation, a modular RC plant, FLSmidth selected the associated equipment – like pumps, screens, dewatering equipment and conveyors – for optimal performance. These modular plants are also automated, using advanced instrumentation and control equipment to keep operations consistent and recoveries high.