News

Wear Protection for Mining Equipment & Processes

Posted on 3 Dec 2012
The Liebherr GET solution is compatible with mining backhoes and face shovels from the R 9100 up to R 9400
The Liebherr GET solution is compatible with mining backhoes and face shovels from the R 9100 up to R 9400

Metso, a market leader in grinding mill liners, is expanding its rubber mill lining production capacity globally by investing in new presses to meet the growing demand in the global mining market. After completing the investment in 2015, Metso’s global rubber mill linings production capacity at the existing wear part manufacturing plants will increase by 30%. The €10 million investment will be completed in two phases. The first set of presses is scheduled to be in operation by the end of 2013. It includes the installation of presses in Chile, Sweden, Canada, Mexico and Peru. Decisions for the second phase will be done based on the demand outlook in early 2013 and implemented in 2014-2015. Metso currently has wear part manufacturing units on six continents.

“This investment is in line with our strategic plans to strengthen our offerings in services business and expand the mill linings availability to meet the growing demand”, says João Ney Colagrossi, President, Services business line, Metso’s Mining and Construction segment.

“We are committed to on-time delivery of parts to our customers. Logistical agility is only assured if our operations are located close enough to the customer sites”, says Rodrigo Gouveia, SVP, Services business line.

Metso Megaliner weighs up to 60% less than a metallic liner of similar size
Metso Megaliner weighs up to 60% less than a metallic liner of similar size

The growing population of large grinding mills and the high utilisation rates of existing mills are driving demand for large, high-quality grinding wear parts. Using large sized liner assemblies reduces the number of pieces to be handled and shortens the duration of the maintenance shutdown.  “Metso has developed mill lining solutions, which combine rubber and a variety of steel elements to optimise the weight, wear life and ease of installation of liner systems. With our state-of-the-art technology, we are able to help our customers to maximise the productivity of their operations utilizing the best selection of materials for each application”, Gouveia adds.

The new Metso MegalinerTM shell liner aims to keep downtime in large mills to a minimum, using an innovative design that offers speedy replacement. It also improves worker safety during maintenance, as the liners are bolted into position from the outside of the mill, so workers do not need to stand in the liners’ ‘drop-zone’.  Mill availability is improved through faster liner replacement. Megaliner uses larger than average liners, yet these can still be placed with the same 6- to 8-axis liner handlers used with many large AG mills.  Using larger liners means mills require fewer of them and Megaliner also has fewer attachment points compared with conventional liners, speeding up installation even further. Liners are easily and accurately positioned before bolting with the aid of highly visible, coloured guiding markers.

The Megaliner is suitable for large AG mills with large trunnions and where modern liner handlers are available. Each Megaliner element integrates multiple lifter and shell plate rows, and covers an area up to 4 m2. The rubber / metal composite liner weighs between 30% and 60% less than metallic liners of a similar size.  Overall installing and replacing mill liners can be accomplished with the Megaliner system in a much safer and less stressful way.

Weir Minerals Africa recently received three orders for Anglo American’s Goedehoop Colliery in Mpumalanga, totalling more than 90 t of dewatering screens of various sizes as well as spare parts for the mine’s stockholding. Weir Minerals Africa’s Chris Dorlas says the first order, placed by the colliery, calls for 10 Linatex® VD dewatering screens. All screens feature 3CR12 stainless steel deck frames to combat corrosion and each one has been test-run for eight hours to ensure that it works to the required performance levels.  “These dewatering screens incorporate a 45° sloping back deck section, fitted with slotted apertures across the direction of flow,” Dorlas explains. “Incoming slurry is fed uniformly along the top of this back section, which acts as a vibrating drainage panel. The main deck of the screen slopes upwards at 5° and is fitted with smaller slotted apertures.
Weir Minerals Africa recently received three orders for Anglo American’s Goedehoop Colliery in Mpumalanga, totalling more than 90 t of dewatering screens of various sizes as well as spare parts for the mine’s stockholding. Weir Minerals Africa’s Chris Dorlas says the first order, placed by the colliery, calls for 10 Linatex® VD dewatering screens. All screens feature 3CR12 stainless steel deck frames to combat corrosion and each one has been test-run for eight hours to ensure that it works to the required performance levels. “These dewatering screens incorporate a 45° sloping back deck section, fitted with slotted apertures across the direction of flow,” Dorlas explains. “Incoming slurry is fed uniformly along the top of this back section, which acts as a vibrating drainage panel. The main deck of the screen slopes upwards at 5° and is fitted with smaller slotted apertures.

Looking generally at the sector, Weir Minerals reports that the cost of installing and operating a new coal mine, for instance, “has increased nearly threefold in the last few years. The story is nearly the same around the globe and no one anticipates any relief in the near future.” The hard rock industry also faces such escalating costs. Many mines around the world are looking at their equipment and focusing on maximizing efficiency and productivity to get more with less.

The Nordic steel distributor Tibnor, a part of SSAB, is an important player when more ore is to be mined in northern Sweden. More than 1,000 new ore wagons have been constructed by Kiruna Wagon, with Tibnor supplying the steel for the ore baskets. The 50th train set is currently under production. In total, 15 new train sets for Malmbanan (the iron ore railroad) are involved, with 68 wagons in each set. Kiruna Wagon is constructing the wagons, which have been ordered by LKAB. Each wagon has an ore basket capable of carrying a load of 100 t. The ore baskets are manufactured of laser-cut and laser hybrid welded steel from Tibnor. The transaction represents part of a new customer concept within the SSAB group, in which deliveries of advanced high strength steels are combined with logistics and production services.

The LockLift (shown here) and Safe-T Lift lifting devices are used in conjunction with CME’s Linersafe range of manganese crusher wear liners. This partnership should allow Boral to realise cost savings through a choice of different liner grades and manganese percentages, chosen from the wear liner range
The LockLift (shown here) and Safe-T Lift lifting devices are used in conjunction with CME’s Linersafe range of manganese crusher wear liners. This partnership should allow Boral to realise cost savings through a choice of different liner grades and manganese percentages, chosen from the wear liner range

“The transaction is an affirmation that complete solutions, in which SSAB’s steel knowhow is combined with Tibnor’s services, create customer value,” says Mikael Jansson, Director at Tibnor’s Marknad Sverige. “With this new customer concept, we are exploiting our shared expertise to an even higher degree than previously.”

The steel selected for the ore baskets is hot rolled DX 355 MCE and DX 650 MCE from SSAB.  Tibnor is co-ordinating the flow of material and laser cutting the steel at its subsidiary, EM Eriksson, with production in Borlänge. EM Eriksson laser cuts ends and sides, and bends top beams and cross bars for the ore baskets.  Thereafter, the steel proceeds to Duroc in Luleå, which carries out laser hybrid welding, before Kiruna Wagon completes the production.

Ted Anderses, CEO of E.M. Eriksson explains:  “We were acquired by Tibnor in the summer and, by being able to contribute our expertise to this solution, it feels as if we are already an integral part of the SSAB group.”  LKAB’s iron ore wagon design in high strength steel was nominated to the Swedish Steel Prize in 2008.

News from the other side of the world has Crushing and Mining Equipment (CME) to be the primary supplier of crusher wear parts to Boral Construction Materials’ Australian operations in all states except Victoria and Tasmania, where it will be the secondary supplier. This agreement provides for the supply of CME’s manganese wear products for cone, jaw, gyratory, VSI and HSI crushers while CME will continue to supply a range of crusher and screen parts as well as providing on-site and off-site servicing and labour to more than 40 Boral sites Australiawide.

One of Boral’s central tender requirements was for the safe lifting of crusher liners. This was a contributing factor in CME’s selection as it will provide its patent-pending LockLift and Safe-T Lift lifting systems. These were developed in response to safety issues associated with lifting crusher liners and providing quick, reliable and zero-harm servicing capabilities.  CME’s proprietary wear modelling software will provide Boral with application specific performance at the lowest total operating cost by matching the optimum profile with the most appropriate grade of manganese steel.

Protecting pipes and more

Weir Minerals Linatex introduced its new Linatex® Wear Indicator System at the 2012 MINExpo International in September. This, it says, “is a revolutionary early warning system for hoses that handle highly abrasive materials in mining operations. The Linatex Wear Indicator System has a 24-hour monitoring system that transmits and receives information, relaying the message to operators onsite.

Geoff Moore, Divisional Sales and Marketing Director, Weir Minerals explains: “With the Linatex Wear Indicator System, mine operators can create a safer environment for employees and the surroundings by closely monitoring the wear on equipment and proactively planning equipment maintenance”

Within a short period of time highly abrasive material puts extreme wear and tear on the hose, causing operation shutdowns and extended periods of maintenance downtime, along with physical inspection. The Linatex Wear Indicator System provides a solution to many of the traditional issues surrounding the maintenance of hoses in highly abrasive environments.

Linatex Wear Indicator
Linatex Wear Indicator

A standard wear indicator system only checks for a break in the wire (continuity) to detect a go/nogo hose failure point, but the Linatex system is constantly searching for wear and tear throughout the hose. When an area is detected it transmits messages, allowing maintenance to become a proactive process rather than a reactive one.

The system senses a change in resistance (measured in ohms). This precision measurement provides more accurate results.  Water, being a conductive media, could cause a false positive, making the hose appear to have more wear life than it actually had. The Linatex system can therefore be used with conductive or non-conductive slurries with confidence, states Linatex. With the 24-hour monitoring system there isn’t a need for operation shutdowns for physical inspection or costly emergency maintenance downtime.

Paula Russell, Hose Product Manager at Weir Minerals – Linatex told IM: “An oil sands hose may weight over 6 t and convey material at over 500 psi – wearing through a hose like this to the point it bursts or leaks material can be at a minimum a maintenance nightmare and at worst an environmental disaster. Maintenance and safety mangers alike need a proactive sensor to alert them to when a hose is nearing its end of life and action needs to be taken.”

A Hose Transmitter can be paired with each hose and report the hose condition daily. This data can be transmitted over distances of more than two miles depending upon site conditions. Data collected by the receiver is transferred to a PC via a communication link to the Linatex Wear Indicator System software program. This displays identity, location and wear status of hoses, including alarms without requiring maintenance teams to visually identify potential wear in a hose.

CertainTeed and Innoveyor teamed up to demonstrate the benefits of high-impact, restrained-joint PVC pipe at MINExpo 2012. CertainTeed’s Certa-LokTM YelomineTM restrained-joint pressure piping system was displayed as well as Innoveyor’s YeloRoll® conveyor rollers, which are manufactured with Yelomine pipe.  John Coogan, Channel Marketing and Communications Manager for CertainTeed’s Pipe & Foundations Group explained that “for the past 40 years, Yelomine has been a reliable choice for mining operations around the world. Its specially formulated PVC compound is perfectly suited for the rigours of today’s mining operations.”

Engineered for strength and endurance, Yelomine pipe contains impact modifiers for higher impact strength over extended periods, with average impact values up to five times greater than conventional PVC, it reports. It is extremely resistant to harsh environments, acids and most chemicals, and won’t rust or corrode.  Yelomine also includes ultraviolet inhibitors that allow the pipe to be used in exposed aboveground locations.

Innoveyor’s YeloRoll rollers are designed for a “drop in” retrofit into customers’ existing conveyor idler frames. The company says the “YeloRoll conveyor idler roll is 60% lighter, helping to prevent injuries and is 50% quieter than metal can rolls. In addition, it won’t rust, corrode or damage conveyor belts and can be recycled or rebuilt for future use.

Richter Chemie-Technik manufactures fluoropolymer PFA/PTFE lined corrosion resistant process pumps and valves and is looking to increase its penetration in the mining sector. Its focus is on highly corrosive applications where the application cannot sustain conventional metals (cast iron, carbon steel, stainless steel 304 + 316) or standard plastics (PVC, PP) “because these would not resist the corrosion,” Manfred Kluge, Manager Marketing & Business Development explains.  “Instead customers would either have to select PFA/PTFE lined equipment (like ours) or go with more expensive equipment made of special metals like Duplex, Hastelloy, titanium etc.  “Besides high and highest corrosion our products can also resist temperatures to 150-200°C and pressures to 16-20 bar.”

Victaulic has introduced the AGS Vic-Ring System that eases the installation of and provides a strong connection for large-diameter pressure piping systems up to 1,525 mm, while extending the service life of abrasive services piping.  The system consists of Style W07 rigid AGS (Advanced Groove System) couplings, style W77 flexible AGS couplings and specially designed rings containing a patented AGS groove profile.  Rings are butt welded to the pipe-ends, and the coupling is assembled on two rings-one on each pipe end-to complete the joint. Style W07 couplings create a completely rigid joint, while Style W77 couplings allow limited linear and angular pipe movement at the pipe joint that can be used to accommodate thermal expansion and contraction, vibration, seismic movement and other applications requiring flexibility.

It simplifies the installation of large-diameter piping systems. The unique wedge-shaped key profile of the AGS groove results in easier initial assembly alignment. In addition, couplings 660 to 1,525 mm feature lifting lugs integrated into the housings to help ease handling during installation.

The AGS Vic-Ring System can extend the life of abrasive service piping systems by maintaining the full pipe-wall thickness and creating a smooth flow path. The centre lip of the coupling’s FlushSeal gasket creates a barrier between the pipe ends, ensuring a smooth flow path and allowing the couplings to be used on lined pipe. In addition, the couplings allow the pipe to be easily rotated, further extending the life of the system. The AGS Vic-Ring System is ideal for large-diameter slurry and tailings lines, as well as other abrasive services.

Feeders, screens and crushers

Abreco Octagon Buttons (code AI-206) that were installed on the lower shell of a 60 x 89 gyratory crusher in March 2006 for Iron Ore Co of Canada. Over three years, maintenance on the lower shell was virtually eliminated with only minor repairs on regular service days. Removal of the spider and mantle is not required for initial installation or button replacement, saving valuable downtime
Abreco Octagon Buttons (code AI-206) that were installed on the lower shell of a 60 x 89 gyratory crusher in March 2006 for Iron Ore Co of Canada. Over three years, maintenance on the lower shell was virtually eliminated with only minor repairs on regular service days. Removal of the spider and mantle is not required for initial installation or button replacement, saving valuable downtime

Keith Holbrook, President, explained to IM that Canadian Wear Technologies is “a manufacturer and manufacturer’s representative of premium wear resistant materials, covering basic to advanced wear protection. Our manufactured material is trade named Abreco and consists of a cast chrome white iron wear layer that is metallurgically bonded to a mild steel backer plate.

“Chrome white iron is renowned for its wear resistant properties, however on its own, it has two major deficiencies; 1) at 700+ BHN (63 Rc) it may fail under heavy impact and 2) this type of white iron in not readily weldable. The Abreco process of metallurgically bonding the white iron wear layer to a mild steel backing overcomes these two deficiencies providing impact resistance and weldability. Engineers can now specify chrome white iron in applications they would never have considered before, such as primary crushing circuits. In addition to the standard inventory products such as Chocky Bars, Buttons and Skid Bars for the GET side we specialise in custom design products for fixed plant.

“The Abreco wear system has been field proven for five years in hard rock mining to significantly reduce operating cost and increase equipment uptime. We have successfully extended the life of transfer points in conveying systems from six weeks to 12 months and apron feeders from 6 months to 24 months and liner changes in the surge pit area have improved from 15 liners every two weeks to 12 liners every 13 weeks.

In order to increase the reliability of the primary crusher discharge apron feeders at an Iron Ore Company of Canada facility, a new type of liner was designed and tested. The aims were:

■ Safety: in that the old style Chrome Carbide Overlay (CCO) liners were difficult to handle during installation with many finger pinch points

■ Weight: The new liners had to be no heavier than the old style liner

■ Increased service life: a target of twice the service life of 12 mm + 12 mm CCO liners was set.

The Abreco Honey Comb liners supplied were thicker than the old style CCO liners yet weighed the same, and were much easier to handle. The unique Honey Comb design allows the ore to be trapped in the pockets creating material on material wear.  After two years of experience with the Honey Comb Liners they were shown to last seven times longer than CCO – an estimated 61 Mt of throughput before replacement. Furthermore, new style Abreco bottom skirt liners showed the same results.

Commenting on the “great improvement in wear life in our crusher discharge apron feeders” after some years, Charlie O’Keefe – Supervisor Crusher Maintenance noted: “The cost is higher but it is well worth it when you have fewer interventions for maintenance and improved up time for production.”

Abreco is also proving itself in abrasive slurry pipe applications. Holbrook explained that “AbrecoPipe is the world’s first and only “centrifugally cast, bimetallic white iron, seamless and UT testable wear pipe” that can be formed into long radius bends. It outlasts chrome carbide weld overlay pipe in highly abrasive oil sands tailings lines by a factor of seven.”

Jeffrey Rader, part of the TerraSource Global group, says its NF electromechanical vibrating feeders “are precision-tuned near their own natural frequencies. They are ‘in tune’ with the materials they carry. These sub resonant tuning characteristics ensure efficient material transference, promote quieter operation, and reduce energy and maintenance costs.”

The computer-designed deck with rugged drive structure handles large lumpy materials with greater reliability. Importantly for wear, the positive drive cog belt eliminates high-tension friction and reduces wear commonly associated with V-belt drives.  Maintenance costs are reduced because frequent belt adjustments or replacements are not required. Constant belt tension prevents slippage, extending bearing life.

W.S. Tyler featured its Pro-Deck System at MINExpo 2012 – a new approach to maximising a screening system. The Pro-Deck approach implements an analysis and modification strategy in processing operations to maximise screen productivity and minimise wear by selecting the appropriate type of screen media according to the three phases of screening. This consultative approach results in a fully optimised screening process for greater efficiency and productivity, as well as less unscheduled maintenance and extended screen life.

Wear-resistant materials

Ruukki, one of the world’s leading producers of high-strength and wear-resistant steel grades, was described in detail in the recent Nordic technology focus (IM, October, 2012, pp57-58).  Ruukki Raex wear-resistant steel has been engineered to withstand even the most demanding conditions, making it a safe, costeffective choice for the needs of mining. For end users, the excellent wear-resistance properties of Raex mean less wear in structural components, which in turn results in the longer service life of components and machinery. Raex allows innovative engineering and lightweight structures with enhanced energy efficiency.

EN Raex improving life
EN Raex improving life

Raex wear-resistant steel is available in four hardness classes: Raex 300, Raex 400, Raex 450 and Raex 500.  The company says that “use of Raex can usually reduce the thickness of a structure by 30 to 50% compared to ordinary structural steel – without compromising on abrasion resistance. Hardness class 400 is the most commonly used at the global level, but demand is also increasing for 450. Both steel grades have good formability and weldability, in addition to excellent wear-resistance properties.”

Raex 400 steel is an excellent material for long-term, heavy-duty use and parts which are susceptible to strong surface pressure, such as loading areas that have to withstand the impact of rocks. The hardness of Raex 400 is 2.5 times that of ordinary structural steel. Raex 500 is ideal for abrasive environments with extremely high surface pressure, such as excavator buckets. The hardness of Raex 500 is three times that of ordinary structural steel.

By using advanced direct quenching technology developed in-house, Ruukki can quench plates and strips immediately after the hot-rolling phase. This significantly reduces both production time and energy use and enables the mill to deliver plates to customers in record time. Direct quenching offers several benefits:

■ Excellent surface quality, because the surface is freshly rolled without the effects of secondary heat treatment

■ Best in class thickness and weight tolerances, Ruukki says. This is important especially for thin gauges where relative weight control is critical

■ Flexible production capacity ensures fast mill deliveries.

Cabot Corp has just launched TransfinityTM XD7050 reinforced elastomer composite, which extends the wear life of rubber components used in mineral processing plants. This new class of material is specifically tailored for use in mining applications. Mines can benefit from the high durability of this new material that increases the service life of parts, significantly reduces maintenance downtime and cost, and increases output from existing assets.

“Rubber mining components made with Transfinity XD7050 material demonstrate superior mechanical properties and extended wear life when compared to parts made with conventional rubber compounds,” the company reports. “The material delivers superior resistance to abrasion, wet erosion, cutting, chipping and tearing, allowing mineral processing equipment to run up to 100% longer between maintenance shutdowns.” Transfinity XD7050 material can provide wear protection in various applications such as grinding mills, slurry pumps, cyclones, trommels, chute liners, dry screens and conveyor belts. This improved wear life directly impacts plant performance by significantly reducing maintenance downtime and costs on critical equipment which ultimately helps increase plant output and minerals recovery. Transfinity materials have been successfully used in field trials that resulted in 20 to 100% improvements in durability.

Russell Coverley, Cabot Elastomer Composites Business Manager says: “Components made with Transfinity XD7050 material have been proven to last longer and extend service intervals for mineral processing equipment.  These performance and productivity improvements can translate directly into higher profitability and returns on assets for mine operators.”

Cabot’s patented technology uses liquid phase mixing rather than conventional dry phase mixing in order to incorporate reinforcing agents such as carbon black into elastomers.  This technology enables Transfinity products to have a superior level of dispersion of the carbon black which creates composites that are stronger than those produced by conventional mixing. Transfinity products are a Cabot brand of composites made from elastomer latex (a liquid form of rubber) and reinforcing particles, such as carbon black. Through the subsequent addition of curing agents, Transfinity elastomer composites can be moulded or extruded and vulcanised to create shaped elastic parts.

Earlier this year NanoSteel® Co, a leader in nano-structured steel materials design, was awarded its fifth R&D 100 Award, by R&D  Magazine, for the development of a new class of nano-structured powder metal alloys designed for making large scale industrial components.  NanoSteel’s patented designs are the company’s first commercially available materials based on its recent breakthroughs in highstrength steels with exceptional combinations of strength and ductility.

This new class of steels features nano-scale microstructures which can be used in hot isostatic pressing, known as “HIPing,” to form components. These nano-scale structures result in a powerful combination of high tensile strength and elongation properties with high corrosion and/or wear resistance.

“Previous strategies to alter the mechanical properties of steel to form near net shape components with nano scale microstructures have been severely limited by size and total thickness,” said Daniel Branagan, CTO and founder of NanoSteel. “The proprietary chemistries and new mechanisms at the core of our recent breakthroughs have allowed us to successfully engineer steel so that components weighing up to several thousand pounds can be formed with nano-scale microstructures and produced in volume on a large industrial scale.”

Parts formed with NanoSteel’s powder metallurgy can increase dependability in highly stressed and operationally critical applications.  Over its ten-year history, NanoSteel has created progressive generations of iron-based alloys from surface coatings to monolithic steel.  For the mining industry, it has successfully introduced commercial applications of metallic coatings to prolong service life in the most extreme environments.

Carryback on dozer blade before and after ARCOPLATE
Carryback on dozer blade before and after ARCOPLATE

Alloy Steel International has many years of experience in providing services to leading mining companies in 25 countries. According to company founder and CEO, Gene Kostecki, “ARCOPLATE has won the confidence of the largest mining operators with proven savings and a wear life up to six times greater than traditional wear products.  Our company is unique in that we partner with our customers, offering the best wear solutions that deliver savings and amazing returns on investment.  ARCOPLATE has been widely adopted by major companies involved in mining and mineral processing, as well as by leading original equipment manufacturers.”

The product is used in the toughest abrasive environments to protect crusher and bin liners, chutes and a host of other fixed plant. Its slicksmooth surface also greatly reduces material hang-up and carry-back in mobile plant such as truck trays and excavator buckets. Kostecki:  “ARCOPLATE saves on three fronts; reduced wear costs, reduced labour costs and most importantly reduced downtime.”

Abresist Kalenborn is celebrating its 35th year in business this year, manufacturing and installing a wide range of mineral and ceramic based abrasion-resistant protective linings.  Founded in May 1977 as Abresist Corp, its company name changed to Abresist Kalenborn Corp in January 2011. It is part of Kalenborn International, a parent company to 12 subsidiaries with facilities in Asia, Europe, North America and South America.

ThyssenKrupp Steel Europe offers XAR® (eXtra Abrasion Resistant) and says “thanks to their high level of hardness achieved by special chemical composition and quenching and tempering heat treatments during steel production, wear is minimised and lifetime extended”. The first XAR plates were produced more than 40 years ago in Duisburg. Since then, these steels have been continuously improved so that now various grades are available with plate thicknesses from 3 to 100 mm, for a range of applications in mining, such as for earthmoving equipment.

The standard wear-resistant steel grade is XAR 400, which increases product service life to five-fold the lifetime of conventional structural steels under equivalent operating conditions, while simultaneously combining high wear resistance with good cold formability and weldability, the company claims. A heatresistant XAR 400 W is also available for applications requiring high hardness and wear resistance at temperatures up to 400 °C. XAR 450 is used where requirements call for higher wear resistance combined with virtually the same processing characteristics as the standard XAR 400 grade. For particularly abrasive wear, the steel grades XAR 500 and XAR 600 are available, which combine formability and weldability with extreme abrasive resistance. For applications with increased toughness requirements on the wear plate, XAR HT is the choice with its combination of wear resistance and high notch impact strength.

The company also notes that an analysis published by the Institute of Tribology at Mannheim University of Applied Sciences “has proven that within the range of low-alloyed, wear-resistant special structural steels with good processing characteristics, XAR steels with hardness values from 300 to 600 HB represent an excellent concept with regard to steel composition, manufacturing process and microstructure. Extensive tests on the wear behaviour of the materials showed that optimum abrasion resistance is achieved thanks to their high hardness and in particular to the selective alloying with chromium and niobium.  The toughness and cold-formability as well as resistance to impact wear are increased by niobium micro-alloying. Chromium alloying improves wear resistance in aggressively corrosive media. The lean analysis concepts and the low carbon equivalent of the XAR steels make cutting and welding easier and provide better cold forming characteristics with tight bending radii.”  Additionally, a comprehensive technical customer service provides support in all material processing, design and wear questions.

ThyssenKrupp Steel Europe says it “wants to be more than a reliable material supplier. The development and expansion of the worldwide distribution network is aimed not just at guaranteeing the availability and just-in-time delivery of XAR steels to consumers. The close cooperation of the new team Special Products & Services together with first-class steel service centres also enable the supply of prefabricated components.”

Astralloy says its EB 450 “is a liquid quenched and tempered, through-hardened, high impact, excellent abrasion resistant alloy steel. It features a balanced boron modified nickel-chrome-moly chemistry for optimum hardness to toughness ratio.” It offers longer wear life because the through-hardness is more uniform than conventional carbon/manganese steels. Resistance to atmospheric corrosion further reduces surface pitting. It is field proven in major abrasive bulk handling installations.

K-ALOX ceramic lined slag granulator break box repaired by Kingfisher Industrial. The company says “it cost less than the alternative of replacing the old break boxes with new units and it will outperform the OEM’S design by a factor of 6 to 1”
K-ALOX ceramic lined slag granulator break box repaired by Kingfisher Industrial. The company says “it cost less than the alternative of replacing the old break boxes with new units and it will outperform the OEM’S design by a factor of 6 to 1”

AstraWear 400F is a water tempered martensitic steel, with typical hardness of 400 BHN (42.5 HRC), which “offers real response to wear from abrasion,” Astralloy says. “Its resistance, high hardness, and high yield strength, make AstraWear 400F suitable for use in applications that require resistance to wear from scraping or moderate impact. Its resistance to wear makes it up to three times more durable than A572-50 (S355) grade.  AstraWear 400F welds easily and has excellent forming properties, which combine to facilitate processing.”

Kingfisher Industrial has calculated that the cost of repairing plant and equipment such as transfer chutes, hoppers and silos, grinding mills & classifiers, screens and underpans, tanks, cyclones and separators, fan casings, feeders and conveyors averages around onethird that of buying new. “Repair of worn equipment, or perforated pipework is a really viable option at any time, but more so during periods of belt tightening,” said John Connolly, MD of Kingfisher Industrial. “Using a combination of ceramic, metallic and polymer lining systems, we have had overwhelming success in protecting equipment and extending the service life of process plant and equipment that, without intervention, would otherwise have been designated as scrap.

“Our experience is that every installation requiring repair or refurbishment using wear protection has its own specific requirements in terms of lining material. There is no ‘one- sizefits- all solution’, due to the levels of abrasion of different conveyed materials. This contrasts with the procedures in many companies today, where the method of repair with wear protection is almost exclusively based upon applying hard metal deposits using traditional welding methods.

“Although this can work in some instances as a means of extending plant life, it is not cost effective because it does not eradicate the continual problems experienced in many applications.”

By applying the correct lining material, users can actually get more life from their plants than they thought possible. This is also means long term savings on maintenance costs and downtime. In addition, the improved efficiency of the lining material generally results in improved productivity. The latter benefit results from the low friction nature of the lining material, which reduces energy use and allows a greater volume of material to be handled.

Wear protection also lends itself to the repair process, as it offers the flexibility to be implemented at any time during equipment life.  Most equipment is designed to allow access for cleaning, repair or replacement. As long as the substrate of the original equipment is not compromised through excessive wear or corrosion then it can continually be repaired in situ. Even if the substrate is compromised, Kingfisher says it can be brought back to a suitable working condition for reuse by replating, incorporating suitable surface preparation and protection.

Ground engaging

MTG has started a test period at its new plant in Monzon, Spain. The plant should be fully operative on the first quarter of 2013. It has been built specifically to expand the company’s mining product range and towards new markets, especially targeting emerging countries. The new plant is equipped with the most innovative technologies in smelter manufacturing and will increase the annual production of wear parts: teeth, adapters and shrouds for mining machines. Initial annual production is 10,000 t with the possibility of increasing significantly its capacity in the future.

During MINExpo, MTG presented its first solution for electric cable shovels. The adapter, known as “whisler” is made with MTG Steels, which, it says, have been proven to be significantly more resistant than the competition. It can be combined with MTG’s new tooth TMA500WH1, which has been specially designed for use on electric cable shovels. The whisler is currently under test under the hardest, real conditions to ensure the maximum quality is achieved under any application.

MTG has four new sizes for its hammerless StarMet system, featuring the bilateral MTGTwist fixing. It gives excellent penetration and more wear material; self-sharpening designs; easy assembling/disassembling; maximum strength and resistance and long adapter service life
MTG has four new sizes for its hammerless StarMet system, featuring the bilateral MTGTwist fixing. It gives excellent penetration and more wear material; self-sharpening designs; easy assembling/disassembling; maximum strength and resistance and long adapter service life

Additionally, MTG launched four new sizes for its acclaimed hammerless StarMet system. With the new available sizes 15, 20, 30 and 40, especially designed for construction, MTG fully completes its product range offer for construction, heavy construction and mining.

The new StarMet sizes are available on the most popular MTG designs. The new product’s main innovation is, the company says on “the lightest and the one with the shortest tooth nose available on the market. They incorporate the new Bilateral MTGTwist fixing system.

Esco debuted its Nemisys lip system at MINExpo. The system features a cast or plate lip with shrouds and a three piece tooth system for large mining buckets. Nemisys is now available for hydraulic mining excavators in the 300 to 800 t classes. The system will also be made available for cable shovels and draglines.

Esco engineered the Nemisys system from the ground up. The lip, shrouds and teeth were developed simultaneously under a new engineering process designed to maximise a machine’s productivity. “The Nemisys system was designed to give customers a safer and highly productive solution to their mining needs,” said Jon Owens, Senior Vice President and President of the Engineered Products Group. Testing of the new system indicates that compared to legacy systems, the lip design and ground engaging teeth require on average 10% less force to penetrate; teeth have up to 19% more usable wear metal; and the system on average weighs 7% less.

These improvements provide increased productivity and reliability while reducing maintenance costs. Integral hammerless locking devices on points, adapters and shrouds and improved ergonomics also make the system safer for customers.

Esco Nemysis system
Esco Nemysis system

Joy Global and Esco recently entered into a strategic business alliance. The first phase of which is the development of new lip systems with Esco technology for P&H® shovel dippers.  Joy Global Surface Mining will offer Esco’s proprietary lips and GET systems as standard on new P&H shovel dippers and loader buckets unless a customer specifically requests an alternative GET system. Esco will service the aftermarket on all lips through its distribution network.  Engineers from both companies will be collaborating on enhanced designs to improve reliability and productivity, while at the same time reducing lip and GET maintenance needs.

Liebherr has developed a complete mining Ground Engaging Tools (GET) solution to complement its mining shovel bucket design.  This synergy enables easy material penetration while extending the life of the bucket. The so called “Z Tooth System” is available in three profiles to cover an extensive range of application types, from well blasted material to very hard ground.  The long-drawn pointed shape of the CLprofile provides a sharp cutting edge for superior penetration in rock and blasted material up to medium compacted ground.  With its wide, thick tooth sole the CR-profile delivers long service life in abrasive soils and blasted rock applications, and perfectly fits for a bottom dump bucket configuration.  The pointed shape of the P-profile offers optimal penetration for very hard and compacted ground applications.  Thanks to the self-sharpening teeth design, machine operators should find an optimal combination of bucket penetration and high fill factor over the life of the teeth.

To reduce parts inventory Liebherr has designed a single wing shroud and corner wear caps for each model, interchangeable from left hand side, right hand side and top to bottom. To increase machine uptime and reduce tooling to one unique extraction tool, the teeth, shrouds and wing shrouds are equipped with one single locking system. In addition, the wear cap does not require any locking system as it is slipped on the adaptor and locked by the tooth.  With its unique hammerless locking system, the replacement of the teeth and the wing shrouds is simple: the securing pin, the tooth, and the adapter are quickly locked by a 90° tool manoeuvre.

Black Cat Blades produces a complete range of quality wear parts for all OEM brands of earthmoving equipment – loaders, excavators, dozers and graders. Blades and end bits are fabricated using high alloy boron steels and heat treated to exacting specifications to meet the demanding needs of large earthmoving applications. High carbon alloy steel is used to manufacture many grader blades. Black Cat says “HighSpec alloy steels and strict heat treatment tolerances are used to ensure all cast wear parts are of the highest quality possible.”

Bradken says it is the global leader in crawler shoe manufacture for excavators greater than 200 t. A recent success story was in gold mine in Tanzania, where harsh conditions can significantly increase the operating cost of the RH340 face shovels in operation there. The mine decided to install a set of Bradken Opti-Trak® crawler shoes after the original OEM shoes fitted to the machine were replaced after 16,000 machine hours.

Bradken says “the Opti-Trak design offers some unique advantages over the OEM crawler shoe design. The substitution of the circlip retaining system with a nut and bolt has eliminated the downtime associated with circlip loss. The performance of the Opti-Trak shoes to date has been very impressive.” After 8,000 machine hours the shoes were showing no abnormal wear on the pins, drive lugs, bores or roller path. “The through hardened material provides consistent wear rates, whilst the improved roller path support provides greater structural integrity.”

Boundary Equipment has an extensive line of replacement parts for Terex O&K RH120E, RH170, RH200 & RH340 mining shovels. It has been producing high quality undercarriage parts for the worldwide mining market for more than 30 years. Boundary can supply track shoes, Boundary PosikeepersTM, drive tumblers and front idlers to replace O&K undercarriage parts and says “if we don’t have the part you’re looking for, we can engineer it.”

All replacement products for O&K parts are made to Boundary original specifications and result in genuine quality parts. Boundary Posikeepers are designed to last the life of the undercarriage and are a cost effective way to protect the pin bore and increase pin life. Track shoe pricing includes pins and Boundary Posikeepers.

Founded in 1978 initially as a mobile welding repair and refurbishment business Miller cut its teeth in the mining and quarrying industry.  Offering a 24/7 service, the small Miller team back in the late 1970s was kept very busy constantly repairing worn buckets, attachments, dump truck bodies and other associated on-site plant equipment and machinery.

Finite Element Analysis (FEA) used by Miller provides predictive performance in respect of loads and stress
Finite Element Analysis (FEA) used by Miller provides predictive performance in respect of loads and stress

Repeated failures in the same areas got the Miller brothers Keith and Gary thinking that “this has to be a design issue” and it was this initial thought process way back in those early years that led the way to Miller designing its own bucket range.  Recognising early on in the then fledgling Miller company that to build a good business with a strong brand it must be able to offer customers real value and to do this it had to offer products that made a difference to their working environments. In most cases back then much debate was held over the machine, engine and productivity outputs but very seldom was any time spent discussing the bucket design, ironic when one considers it is actually this part of the machine that is responsible for loading and therefore has a huge impact on the machine’s overall output. This intrigued Miller as it began to look at how to use its product knowledge to design and develop improved buckets that would not only minimise buckets failing in the specific areas that they were becoming notorious for but also to look at incorporating into these designs new ideas on how to reduce wear, in other words extending the life of the bucket and so delivering customers more machine up time.

Over the years with now countless numbers of ‘custom’ built bucket designs working worldwide Miller still continues to look at extending bucket life through a variety of solutions which can vary dramatically from application to application.  “We pride ourselves still on offering our customers a service like no other” explains Gary Miller, Technical Director. “We want customers to come back to us again and again so we spend time finding out about how to tackle their wear issues and what causes them the most downtime. Once we understand this we can build a solution to satisfy their exact requirements and not a standard off-the-shelf design, which will do a job but maybe not return the productivity the customer is looking for.”

As the industry continues to change on a global scale so too does the demand from customers for improved cycle times and less wear. All sorts of options must be explored when trying to find the right solution, from new lighter, longer life steel grades to the latest wear packs and tooth designs from the various wear part suppliers.

“Whilst we will never stop buckets or machinery wearing out, we can certainly reduce impact on machine productivity. Of course quality and longevity come at a price but on large mining projects around the world so long as the return on investment shows an improvement then companies like Miller will continue to play an important role in developing new ideas that help keep mines across the globe running for longer,” says Keith Miller, Chairman, Miller International.

GET underground

Keech Wearpact bucket edge system for LHDs
Keech Wearpact bucket edge system for LHDs

A group of five mining contractors in Chile’s copper and gold mines is reporting impressive results from trials of the Keech WearpactTM bucket edge system on a fleet of underground loaders. The trials are at varying stages, following the start of the first trial over a year ago.  Wearpact is a patented ground engaging tool designed for both underground and open pit mining.  Heavy duty edges and corners perform under all loading conditions, keeping wear consistent across the edge.

“We made a business decision to enter the Chilean market because we saw a real opportunity to make a difference,” said Keech International Sales and Marketing Manager, Mark Adams. “We appointed a business development manager two years ago and regular visits to Chile by myself to oversee trials and their implementation has proven invaluable in getting to know some of the leading contractors and talking to them about our Wearpact system.”

After 12 months of the first trial – “2,000 hours with the Wearpact system showing no problems whatsoever. We may be able to get as much as four times the life out of the bucket thanks to Wearpact,” he said.

Prior to installing the Wearpact system, the loader buckets needed to be transported many kilometers to Santiago for repairs.  After 1,000 hours in the second longest running trial, that contractor ordered two more Wearpact systems for the other loaders in the fleet. “Keech Chile now has purchase orders from contractors for another 10 Wearpact systems, which will be fitted to other loaders in the fleet over the coming months,” Adams said.

Back in Australia, a new mechanical bucket is dramatically reducing the time required to replace edge wear systems on underground LHDs. The Keech Mechanical Bucket (KMB) features a complete bolt-on section at the front of the bucket, differing from standard buckets on the market.

The KMB is on trial at the Newcrest Cadia East gold mine in Orange, New South Wales, following a 12-month development phase. The mine is trialing a 12 m3 bucket with an Armourblade edge system on two underground mining loaders, “and the results so far have been outstanding. “The KMB bucket front with the Keech ArmourbladeTM edge system can be replaced within three hours on site. Operators simply unbolt the front section and replace it with a new one,” explained Adams.

“Given that the edges on some buckets need to be cut off, which can take up to 35 hours, the KMB is likely to generate significant efficiencies for underground mine applications.”  The ease of removal of the front section also means the bucket can run a welded edge, making it ideal for use in cautious areas such as crusher zones, while still maintaining a quick change out during underground operations to minimise downtime.  The KMB is compatible with both Wearpact and Armourblade edge system. Wearpact is a hammerless GET system, available in full spade and semi spade configuration, while Armourblade is a welded edge system.

The Newcrest Cadia East trial is also evaluating actual edge life, which to date has tested at approximately 1,000 hours. “We’re currently investigating how we can extend this to 1,200 hours plus, and are looking at redesigning the corners, which are usually the fastest wearing area, through the addition of tungsten carbide inserts,” explained Adams.

The buckets have been developed by Keech in conjunction with Canadian company Carriere Industrial Supply and are available in a range of sizes from 7 up to 12 m3. They are manufactured from quenched and tempered steel, and Keech works with each customer individually to customise a wear protection system to suit the application at hand. The bucket is suitable for all LHDs. IM