All posts by Coral Fraser

CHECK GENSET DIESEL INJECTORS AS FIRE RISK RISES

South Africans have been dismayed by a spate of destructive fires around the country, highlighting the need for diesel-powered fire pump systems to be at the ready and in good working order.

Andrew Yorke, director at Germiston-based Reef Fuel Injection Services, says the drier season approaching in most provinces is once again raising the fire risk. Yorke notes that municipal fire services are often under-capacity, and new buildings increasingly require their own water storage tanks and pumping facilities in case of fire.

Governor repairs underway at Reef Fuel Injection Services to a six cylinder genset pump.

“The problem is that the diesel engines driving these fire pumps stand idle for long periods,” he says. “This is not good for the fuel or the engines, particularly the diesel injection systems. Now is a good time to have these checked and serviced.”

Blockages or malfunctions in the fuel injector system could mean that the engine does not start at all. Alternatively, it could mean significant underperformance of the pump and even engine damage and premature failure. 

“A fully functioning water pumping system is vital for companies to respond quickly and effectively to fires, which can save millions of Rands in damage and avoid crippling business disruption,” he says. “Servicing the injector and fuel pumps is a low cost exercise that can be carried out quickly by our qualified technicians. In fact, it should be regularly scheduled as an integral aspect of the company’s safety plan.”

In this servicing procedure, a technician checks and flushes the fuel pump and injectors, and tests the calibration. Components can then be repaired, if required. This should ideally be done every six to 12 months, while the diesel engine itself should be started and run at least once a month.

Yorke also points out the seriousness of the damage that can be inflicted on a diesel engine by running it with a faulty fuel injection system.

“Water pumps and generator sets – unlike vehicles – immediately accelerate to operating speed when they are started up,” says Yorke. “As a result, faults in the system can quickly cause considerable damage before they are detected. Such damage – which could extend to catastrophic engine failure – is much more expensive to repair than the cost of servicing the fuel injectors regularly.”

“These simple checks will help ensure that the company’s extensive investment in firefighting capacity is put to good use when the occasion demands it,” he concludes.

PILOT CRUSHTEC RENEWS PARTNERSHIP WITH METSO OUTOTEC

After five successful years representing global leader Metso Outotec in southern Africa, Jet Park-based Pilot Crushtec has renewed its distributorship for another five.

Despite periods of challenging economic conditions in recent years, Pilot Crushtec has earned global accolades within the Metso Outotec distributor network. According to Francois Marais, director sales and marketing at Pilot Crushtec, the company has already won annual awards for Best Aftersales Distributor and for Best Sales Growth. 

“We value this partnership with one of the world’s leading brands, and have demonstrated through our solid performance the positive synergies that we leverage,” says Marais. “The years from 2017 through to 2019 in particular saw exceptional growth year-on-year for both our Metso Outotec offering and our business as a whole.”

He highlights that the two companies’ offerings in the crushing and screening market complement each other very well, and they share a commitment to high quality products, services and support. 

“For customers, the renewal of our distributorship confirms their faith in our products and strengthens their security of investment going forward,” he says. “It assures the market once again that their capital investments are being well supported through our extensive parts holdings and service excellence.”

The new agreement covers additional products and territories within the region, facilitating a wider offering in terms of new equipment and aftermarket aspects. According to Adam Benn, director capital sales North EMEA, Russia & CIS and Southern Africa at Metso Outotec, there was no hesitation in signing a renewal of the distribution agreement with Pilot Crushtec.

“Having just celebrated its 30th anniversary in business, Pilot Crushtec has built a strong reputation,” says Benn. “This applies not only to their supply of equipment and associated services, but their experienced team’s hands-on knowledge and can-do attitude to opportunities and challenges.” 

He emphasises Pilot Crushtec’s investment in time and resources training their teams and their customer base – an effective strategy for keeping skills current and for listening to customers’ development needs. With technical facilities that rank among the industry’s best, the company manufactures plant locally while also offering a one-stop repair and refurbishment solution.

“Having a distribution network that is close to its customers is a fundamental part of Metso Outotec’s group strategy,” he says. “In addition to being well located, our distributors need to keep a good inventory of equipment and parts, which is something that Pilot Crushtec prioritises as a vital cornerstone of their business strategy.”

Looking ahead to Metso Outotec’s future focus, Benn says that business is returning to normal with the construction segment proving resilient with recovering activity levels. 

“The short-term focus will be on continuing to strengthen our products and services, while working on developing the next generation of technology and solutions required by our customers,” he says. 

NO SHORT-CUT TO CHUTES THAT PERFORM – RELIABLY AND SAFELY

While there are many ‘look-alike’ transfer chutes on the market, it is the demanding original equipment manufacturer (OEM) standards of Weba Chute Systems that keep mined material as well as industrial materials moving smoothly. 

“Through our focused dedication for many years, we have developed the design, engineering and manufacture of transfer chutes into a science,” says Weba Chute Systems technical manager and designer Dewald Tintinger. “This is what gives our customers the peace-of-mind that their operations will not be disrupted by unplanned stoppages due to premature chute failure.”

Tintinger points out that a chute is often viewed – quite erroneously – as just a platework commodity that any general manufacturer or fabricator can produce on demand. 

The danger in this approach is that the performance is generally not optimal, the reliability is certainly not guaranteed, and there may not be any technical backup when it is required.

“Our extensive design capabilities are leveraged by our experience in the field, where we are constantly installing or improving systems to support our customers’ specific requirements,” he says. “This is why every transfer point solution is custom-engineered, based on our in-depth assessment of the material and operating conditions on site.”

The design is from the ground up, with skilled draughtsmen using the latest specialised software to model material flow in line with operational needs. This facilitates optimising the material trajectory into the chute, out of the initial impact area, through the chute itself and into the discharge area.

Once a Weba Chute Systems product is installed, it can be regularly inspected and maintained by specially-trained technicians, making sure that it reliably delivers the duty required. 

“We stand by every chute we produce supporting the customer to ensure smooth production flow,” Tintinger says. “Where the provenance of the chute is not clear, plants often do not know where to turn when problems arise.”

He also highlights the value of engaging specialists from Weba Chute Systems at the early stages of plant planning, in terms of positioning equipment for optimal material flow through the plant. 

“With our detailed knowledge of how transfer points or chutes work best, we can offer valuable guidance at planning stage about where the chutes – and hence certain other equipment – should ideally be positioned to improve efficiency and results,” he says. 

He emphasises that transfer chutes, while ranking as relatively low cost items in the broader scheme of process equipment, can be the source of costly and major operational problems – all of which can be avoided.

LINATEX HOSE REDUCES DOWNTIME AND OPERATING COSTS AT NAMDEB

The installation by Weir Minerals Africa of a Linatex® 808 hard wall rubber hose with wear indicator system is reducing downtime and operating costs at Namdeb’s Sendelingsdrift treatment plant in Namibia.

The challenge facing Sendelingsdrift was that it was changing out the incumbent competitor’s rubber hoses every four weeks due to excessively high wear rates. In addition to the ongoing downtime, the plant also risked losing concentrate due to the hose failures. As the concentrate media contains diamonds, additional security was required when dealing with hose failures that result in concentrate leakage – adding to the costs. 

The Weir Minerals Africa service teams regularly visited Sendelingsdrift to engage with the plant manager, area engineers and other operational staff to get a better understanding of their requirements and problematic applications. After an audit of the site, the team considered all the parameters and proposed a trial of a Linatex® 808 rubber hose fitted with a wear indicator system. 

The proposed solution would be capable of withstanding the slurry flow rate of 84 l/s with a slurry density of 2,65 t/m³. The wear indicator system installed on the hose would indicate when the hose was nearing the end of its life; no physical inspections would be necessary. 

In addition, Sendelingsdrift would save the cost of additional security requirements by eliminating premature hose failures.

Sendelingsdrift agreed to the proposed trial, and the Weir Minerals Africa service team conducted weekly site visits to inspect the hose and the wear indicator system. While the competitor hose generally failed after delivering 32,000 tonnes of ore, the trial showed that the Linatex® 808 rubber hose surpassed 162,000 tonnes.

The hose lasted seven and a half months before being replaced, which was more than six times longer than the competitor’s hose – representing a significant cost saving for the customer. The Linatex® rubber hose processed over 2,5 million tonnes of concentrate and a similar volume of slurry during this time.

Designed for dual delivery and suction applications, Linatex® 808 rubber hose can be custom manufactured to any size and is available with a range of flange types.

RESEARCH STUDY LEADS KWATANI TO BETTER BANANA SCREEN DESIGN

Numerical simulation research that modelled the behaviour of particles on a conventional banana screen has been leveraged by local vibration screen specialist Kwatani to make fundamental improvements in the design.

So important were Kwatani’s adaptations that they were able to double the throughput of a competitor’s problematic dewatering screen on a customer’s mine, where excessive water carry-over was limiting production potential. 

According to Kwatani chief operating officer Kenny Mayhew-Ridgers, the company’s depth of mechanical and metallurgical expertise underpins its ability to apply what it learns from research and field testing. 

“This specific research, which was done by Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the University of Queensland, highlighted that the traditional feed-end slopes of banana screens were generally too steep,” says Mayhew-Ridgers. “At around 34°, these slopes create material velocity in excess of 3 m/s – too high for efficient screening.” 

He considers that a more suitable slope at the feed end is 25°, leading into five or six deck slopes in the screen and ending with a discharge slope of just 5° or even 0°. This would ensure that the material velocity was less than 0,5 m/s at the discharge end. The drive angle, operating speed and stroke are also significant factors, he says.

“Our analysis allowed us to address a challenge that a customer was experiencing with their degrit screens,” he says. “Water carry-over from the screen to the conveyor belt was limiting throughput to only 250 t/h, and the mine needed more than that.”

Kwatani’s changed the screen feed-end slopes and incorporated a long discharge-end decline slope of 3°. The drive angle was also increased to 50° to improve the dewatering performance of the screen. These adaptations were possible within the constraints of existing chute work, motor base position and support structure. The size of the screen – measuring 3,66 m wide – meant that a considerable load needed to be supported on the screen deck, so circular hollow sections provided improved strength in place of the H-profile deck beams usually employed.

“The modifications were successful,” he says. “The mine’s plant manager was able to confirm that  the feed rate had been increased to 500 t/h with very little water carry-over, and this performance was consistently maintained.”

The application of the new design was outlined in a peer-reviewed paper by Mayhew-Ridgers and Kwatani director Derrick Alston, which was presented at an international mineral processing conference. 

POWER UTILITY RELIABILITY BOOST FROM LARGE WEG TRANSFORMERS

Precision manufacturing at the WEG Blumenau factory in Brazil allowed Zest WEG to supply two large, custom-built power transformers a month ahead of deadline to a power utility strengthening the reliability of the region’s power system.

The fact that both 500MVA 400kV transformers passed the factory acceptance test (FAT) first time around paved the way to early delivery. This achievement, according to Jan-Frederik Viljoen, executive  transformers at Zest WEG, is a testament to the company’s design and manufacturing quality. 

The 348 t units are the largest yet produced by WEG – with each unit boasting a power rating of 500,000kVA and voltage class of 400kV. This delivery efficiency reinforces Zest WEG’s position in the local market.

“Our South African team participated actively in this project, reaffirming WEG’s commitment to the development of our employees and the transfer of skills,” says Viljoen. “We see this as a vital contribution to the development of the country, as well as the alleviation of the energy shortage in the region.”

He says the benefits of these transformers include robustness, flexibility and reliability – contributing directly to the development of the local economy. They are also an important element of expanded investment in emergency capacity to generate complementary power supply for the region.

Zest WEG’s manufacturing operations in South Africa include two transformer factories near Johannesburg, which produce and supply the local market with 145kV voltage class transformers. This contract is an important achievement for Zest WEG, which is deepening its contribution to power generation, transmission and distribution as part of its developmental mandate. The company is well-established in the mining and industrial sectors, and is currently raising its level of engagement with power producers and municipalities.

Zest WEG’s portfolio includes power distribution equipment such as miniature substations, distribution transformers and power transformers, as well as packaged switchgear and automation solutions such as E-Houses, Motor Control Centres (MCC) and electrical enclosures. Among its power generation solutions are conventional diesel generators, combined heat and power generation (CHP) and renewable energy generation.

Other offerings relevant to the public sector include the supply of substations and electrical infrastructure, including the design, supply and construction of overhead lines, substation mechanical and electrical construction, and electrical high-voltage and low-voltage reticulation.

GLOBAL EXPANSION AS INTEREST IN BOOYCO PDS GROWS

From its solid foundation as the pioneer of and leader in Proximity Detection System (PDS) in South Africa, Booyco Electronics is making rapid headway in growing its global footprint.

Having recently made export development a strategic imperative, the company is seeing enthusiastic uptake of its home-grown technologies, according to Booyco Electronics CEO Anton Lourens.

“These are exciting times, where we are already doing business in Southern Africa, West Africa, South America and Australia, while seeing considerable interest from countries in Europe and North America,” says Lourens. 

“Expanding our footprint has been made possible by building strong relationships with experienced channel partners who serve and know these mining regions.”

Booyco Electronics’ journey into international markets began many years ago through its involvement with the Earth Moving Equipment Safety Round Table (EMESRT), Lourens notes. This global initiative of major mining companies guides best practice in minimising vehicle interactions and collisions. 

With South Africa leading the world in regulating this space, Booyco Electronics was, and still is, able to contribute valuable insights to this global forum – based on its market leading PDS technology and experience in the field.

“When we began designing our latest Booyco CXS generation of collision avoidance technology, we developed a solution that would lend itself to application in international markets,” he says. “We then identified and engaged reputable partners who understand their customer base and are technically capable of supporting our innovative product line.”

The first Booyco PDS system exported from the South African facility was installed in Madagascar about five years ago. This has been followed by further international installations in Ghana, Namibia and Chile. 

“With our focus on developing safety equipment that ensures every employee returns home safely every day, we collaborate with responsible, diligent partners who apply their technical resources to realising that vision on individual mine sites,” he says. 

Key relationships have been established with Australian smart technology company RCT, with Ramjack Technology Solutions and with Insucam. RCT has operations in 70 countries, Ramjack Technology Solutions provides system integration services globally and Insucam has a strong South American footprint.

“While our channel partners support the technology and the end-customer, there is also significant value-add in our collaboration as our partners are already experts in automation, remote control and interfacing,” says Lourens. “Their experience in on-mine implementation opens doors to integrating our various technologies to the customers’ benefit. We can even incorporate  their technologies into our solutions.”

Positioning Booyco Electronics well for its global growth is its familiarity with most mining environments, based on over 15 years in the field. Its technology has also been developed to address the various scenarios specified by EMERST in its protocols and guidelines. This has meant the company’s PDS solutions have solid global applicability from a technology deployment perspective. 

“We have now been able to enhance this offering by adapting our machine displays and text to different languages to suit new markets, including our manuals and training materials for technicians,” he says. 

“We also provide training – online as well as in person, where possible – to our channel partners. To do this, we leverage the power of video while also experimenting with innovations like body cameras for the more technical aspects of learning and on-site fault finding.”

Lourens highlights that mining professionals in many countries are still relatively new to PDS, as regulations have not required the implementation of this technology previously. This has led to Booyco Electronics focusing extensively on information and training tools that familiarise the international mining sector with the value of this technology. 

It is clear, he says, that PDS technology has much to offer mines globally, especially as mining operations seek digital integration that will continuously improve safety and productivity.

INNOVATIVE SEWAGE POND DREDGING FOR SUGAR PRODUCER

The recent upgrading of sewerage facilities at an Eswatini sugar producer required more than the dredging of a sewage pond – but Integrated Pump Rentals was up to the demanding task. 

Cleaning of a settlement pond usually involves the pumping of high solids material to another nearby dam. In this case, however, there were no containment areas for the sewage on the customer’s site. According to Ruaan Venter, rental development manager at Integrated Pump Rental, an innovative solution had to be found to capture and store the sewage. 

“The pond in question was close to the company’s sugar cane fields, so absolutely no spillage was permitted onto those lands during our cleaning process,” says Venter. 

At the heart of the cleaning operation was Integrated Pump Rentals’ well-proven SlurrySucker mobile dredging unit. On this project, the SlurrySucker Mini was employed, emptying the pond of 30 to 40% solids material at 150 m3 per hour.

“To contain the sewage, we procured specialised geotextile bags measuring 30 m long by 18 m in circumference,” he says. “These were laid out on a large area near the dam, which had been allocated for this purpose.”

Before the sewage could be pumped into the bags, however, it required the addition of flocculant to facilitate the separation of solids and liquid. This was achieved using an in-line dosing system, feeding the flocculant into the pipeline from a 1000 litre tank. Effective mixing in the pipeline could be reached over a 100 m distance of the pipeline. 

“After two weeks, we had filled three of these large bags with the material from the pond,” Venter says. 

As the water separated from the solid material, it was able to drain through the bags’ porous sides and flow back into the pond. The solids could then be left to dry out in the geotextile bags, after which it could be moved from the site and discarded safely. 

AFRISAM WORKS WITH SANTEQ TO BRING THEMBISA SOLID HOMES

In a housing market that is desperate for quality, robust and affordable homes, advanced building technology frontrunner, Sanjo Fabtech Sterling has been collaborating with construction materials leader, AfriSam, to deliver just that in Thembisa. 

At the heart of the 500 unit, fast tracked housing project is Sanjo Fabtech Sterling’s advanced, lightweight wall technology, delivering solid four-storey ‘walk-up’ residential buildings that will be ready by mid-year. According to Jonathan Peel, director at Sanjo Fabtech Sterling, the walling systems used in Thembisa have recently also been used in upmarket Sandton apartments and hotel projects.

AfriSam is supplying an innovative lightweight readymix solution designed and developed by Sanjo Fabtech Sterling’s sister company, SanteQ Liteweight Building Technology, for the Thembisa project. The lightweight concrete mix designs combine recycled polystyrene with SanteQ’s specialised concrete mixes. 

The readymix infill for the walling system is supplied by AfriSam and pumped into the void between the fibre cement boards which acts as permanent formwork. The polystyrene creates mechanical air bubbles, reducing the weight of the walls by 50 to 75% when compared to traditional masonry materials, and offering distinct design and engineering benefits.

“Due to dolomitic soil conditions in the Thembisa area, the weight advantage of the walls significantly reduced the design of the raft foundation.” says Peel. “Despite their lighter weight, the walls are as solid as brick and mortar, pass the ‘knock test’ and provide better sound and thermal insulation.”

“Delivering from our nearby Olifantsfontein plant, we could provide Sanjo Fabtech Sterling with 48 to 102 cubic metres a day of their special mix in our readymix trucks,” said Luigi van der Made, AfriSam’s readymix operations manager. “Using four of our six cubic metre capacity readymix trucks, we were able to add the polystyrene on site and create a homogenised mix.”

The special lightweight concrete mix – which does not use coarse aggregate – includes fine and coarse sands as well as fly ash with the cement. CHRYSO® Omega 140 AFR ZA, a high range, water reducing plasticiser is also included to increase the slump while reducing the water requirement.

“Keeping a constant supply flowing with four dedicated readymix trucks, we ensured that the mix remained consistent, workable and cost-effective,” says van der Made. “The final infill mixture was then be pumped into the walls, speeding up the construction process.”

He notes that the process had to be closely controlled to prevent residual polystyrene in the readymix trucks from contaminating any other process back at the plant. This required a careful cleaning process, which also included a recycling circuit to separate the polystyrene and return it to SanteQ for recycling.  

SOLAR ENERGY ADDS TO CHRYSO’S SUSTAINABILITY JOURNEY

Cement additive manufacturing company CHRYSO Southern Africa has installed a solar electricity generating system at its Jet Park premises in Gauteng, as part of its efforts to lower its carbon footprint.

According to CHRYSO Southern Africa CEO Norman Seymore, the system will generate almost 240 MWh each year to serve the company’s production facility.

“This output will make up about 70% of our energy requirements, with the rest sourced from the national grid,” says Seymore. “One of our three sustainability pillars at CHRYSO is the reduction of energy consumption, and this installation goes a long way in reducing our dependence on South Africa’s notoriously carbon-producing electricity.”

A total of 393 solar panels – each with a capacity of 400 W – were installed on the roof of CHRYSO Southern Africa’s premises in January this year. They will collectively generate a kilowatt peak of 157 kWp through five 27.6 kW inverters. 

“Our investment in solar energy generation is an important contribution to the company’s global commitment to a more sustainable construction sector,” Seymore says. “Our CHRYSO admixture products themselves play a valuable role in driving down the carbon emissions related to construction materials.”

He highlights that these admixtures can help to reduce the cement component of concrete – cement being among the world’s most significant carbon-generating products. CHRYSO Southern Africa is also active in other environmental initiatives, such as ensuring that its packaging materials and containers are recyclable and reusable. The company delivers much of its product range in bulk, but uses recyclable material where products are delivered in 200-litre drums or 1,000-litre containers.

“We have, in addition to our solar installation, also implemented a series of wastewater treatment systems at our plant to reduce and recycle the volumes of wastewater we produce,” he says. “We constructed several wastewater catchment areas to ensure that any discharged wastewater was first treated to an acceptable standard.”