LOOKING AROUND THE CORNER WITH LEUZE

Manufacturing plants, packaging facilities and warehouse operations often have areas where visibility is not what it should be, and not only can these prove hazardous to both vehicles and pedestrians moving in these areas but plant operators have limited visibility as well.

A solution, available from leading sensing solutions supplier Countapulse Controls, is the robust LCAM 408i IP camera which has been engineered for use in industrial environments. Correct positioning of the device will allow visibility into hard to see area with the 5 mexapixel colour camera delivering live stream at high image quality due to its gigabit Ethernet interface,

The housing of the robust Leuze LCAM 408i IP camera is rated at IP65/67 and features an easy to clean glass pane. It is easily integrated into machinery or system controls via M12 connections and requires only a 24 V voltage supply. Flexibility of installation is ensured through diverse mounting options including the use of dovetail, threaded holes as well as an extensive range of mounting accessories.

Configuration is simple and is accomplished via a standard browser and displayed via standard streaming tools. There is no need for additional software, and troubleshooting has been simplified in case of failure.

Countapulse Controls the official distributor of Leuze sensing solutions and products in southern Africa and the company offers industry access to skilled technical personnel that can advise on the application of the products.

CONCOR INFRASTRUCTURE TO CONSTRUCT NEW WIND FARMS

Concor Infrastructure has been appointed, in a consortium with Conco, by global wind and solar company Mainstream Renewable Power as the construction contractor for two large scale wind farms.

The wind farms, located in the Northern and Western Cape, represent an investment of approximately R6.6. billion and construction will commence in June 2018.

Eric Wisse, managing director of Concor Infrastructure, says the company is well positioned to undertake these two major projects with its depth of experience and expertise. He points to the successful completion of the Loeriesfontein and Khobab Wind Farms in 2017 and prior to that the Jeffreys Bay and Noupoort Wind Farms.

“Concor Infrastructure has an established reference base that speaks to our capability and responsiveness, which enables us to deliver complex projects on schedule, within budget, and most importantly safely,” he says.

The 140 MW Kangnas wind farm is situated 52 km east of Springbok in the Northern Cape while the 110 MW Perdekraal East wind farm is about 80 km northeast of Ceres in the Western Cape. The wind farms are expected to begin commercial operation in 2020.

CIVIL ENGINEERING SECTOR CONCLUDES THREE YEAR WAGES AND CONDITIONS OF EMPLOYMENT AGREEMENT

Today, the Bargaining Council for the Civil Engineering Industry (BCCEI) announced the signing between all parties in the civil engineering sector of a three-year settlement agreement with respect to wages and conditions of employment. The settlement will come into force from promulgation by the Minister of Labour later this year.

The negotiations were characterised by a deep understanding by all parties of the pressure under which the civil engineering sector has been operating for the last few years.
The employers were represented by South African Forum of Civil Engineering Contractors (SAFCEC) and Consolidated Employers’ Organisation (CEO) and the employees by the Building Construction and Allied Workers Union (BACWU) and National Union of Mine Workers (NUM).

The parties agreed to a 7.5% wage increase across the board for the first and second year. The increase for the third year will be 7.5% or CPI , whichever is the greater.

Negotiations began in the last week of March 2018, and what is significant is that during negotiations real industry issues were dealt with.

The BCCEI is a sector specific bargaining council created in terms of the Labour Relations Act, 1995 (LRA), and it responsible for overseeing the funds and benefits administration, compliance, enforcement and exemption of the various Collective Agreements concluded within the BCCEI.

RAUBEX RENOVO BRINGS MALL GLAMOUR TO CAMEROON

A modern shopping mall, complete with convention centre and cinemas, will grace Cameroon’s financial capital city of Douala by the end of 2019 – and South African turnkey specialist Raubex Renovo is making it happen.

The €45 million Douala Grand Mall is part of a larger development that will include a five-star hotel, offices and residential apartments being built in the near future.

“The mall and convention centre signals to the world that Cameroon is on the move, and is attracting more visitors for business and leisure,” says Matthys Serfontein, development manager at Raubex Renovo. “Our modern construction planning and methods combine with an energy efficient design to make the mall stand out dramatically from its local competitors.”

Its size, for a start, is significant; it will reportedly be Central Africa’s largest mall when complete with a built floor area of 25,600 m2 including 18,732 m2 of lettable retail on its two levels. Importantly the mall is in the immediate vicinity of the international airport with a primary catchment of 1,5 million people.

The ground floor of the complex will have 14,160 m2 of retail space while the first floor will house 11,520 m2 including a modern conference centre, cinemas, food court and retail space. There will also be underground parking in the basement.

Environmental standards have been followed in the design and construction, complying with the EDGE green building certification system developed by the International Finance Corporation. Using insulated cladded panels for the outside walls and the roof, including double glazing on skylights and shopfronts that allow for the best use of natural light, the building will be the first climate-controlled mall in Cameroon.

Focusing on large hospitality and retail projects, Raubex Renovo’s team has 20 years’ experience of construction projects throughout Africa. The company’s capabilities encompass full project development including professional engineering, architectural and design services all managed by a professional construction and development team.

Health and safety is a core focus of the Raubex Group, with attention paid to all aspects of health and safety as well as environmental and social impacts on Raubex Renovo’s projects site. A zero harm approach forms an integral part of the company’s operating strategy with solid safety programmes implemented to ensure the wellbeing of all stakeholders.

“The efficiency and reliability of our work is enhanced by our use of Building Information Modelling (BIM), allowing us to optimise our design, construction and operations activity,” says Ben Pretorius, managing director of Raubex Renovo. “BIM also ensures that up-to-date information on project progress can be easily shared with all stakeholders and contractors.”

Earthworks began at Douala Grand Mall in January 2018, and handover is scheduled for November next year.

“The project is another example of our team’s capacity to plan and implement accelerated construction programmes across the continent,” he says. “The Raubex Group has a solid reference base of completed projects in South Africa as well as in the SADC region in countries like Botswana, Namibia, Mozambique, Zambia, Gabon, Togo, Malawi, Zimbabwe and the DRC.”

Pretorius emphasises the importance of the reputation and backing of parent company Raubex Group, a leading infrastructure development group with 40 years in the business and a listing on the Johannesburg Stock Exchange.

FLSMIDTH OFFERS ECONOMIC OPTIONS FOR LARGE THICKENERS

Finding the optimal design and delivery solution for a large thickener at a remote gold mine in the West African state of Mauritania meant considering a complex range of technical, transportation and assembly options, according to FLSmidth senior account manager Ricus van Reenen.

The cost of transporting the components for the 50-metre diameter thickener was a key factor affecting the design, says van Reenen. He highlights that transportation of components to remote sites can comprise a substantial portion of costs, and that break-bulk shipping costs are significantly higher than containerised transport.

“Given that the thickener components needed to be shipped by sea as well as by road, containers were considered the most economical mode solution,” he says. “This requires that the plate sections be cut and rolled in dimensions that can be packed into containers for shipping to site.
The structural support sections like the I-beams will be fabricated to final stage at our facility and just bolted on site, but the plates will need to then be welded by expert welders.”

While bolted thickeners are often more economical to construct, as they obviate the need for extensive on-site welding, this option cannot easily be applied to thickeners larger than 50 metres in diameter.

“For these larger designs, the support structure is erected on site followed by the welding together of the plate sections from one end to the other,” he says. “After the plate sections have been welded to the structure, the welds are sandblasted, primed and applied with a final paint coating over the welded areas.”

Certain cost-saving strategies can still be employed in these situations; for instance, the plates can be painted before shipping with the weld-strips left clean to facilitate on-site welding.

Van Reenen emphasises the importance of the documented assembly procedure – according to FLSmidth’s global best practice – that is applied when erecting these large thickeners.

“When supplying a thickener, part of our engineering deliverables includes an installation methodology for the site contractor to follow, to make sure that they implement each stage correctly,” he says. “FLSmidth also provides a technical installation expert from the most suitable of our global offices who visits the site at appropriate intervals to advise and inspect.”

He further emphasises that the forces demanded within large thickeners also makes the choice of gearbox drive much more important.

“Smaller thickeners can usually be designed with planetary gearbox drives – available from a number of OEMs,” he says. “With really large drives requiring higher torque, however, we prefer to use our own ring-gear Dorr Oliver drives which can reach much higher torque values than planetary drives.
The ring-gear drives are also more able to handle axial and radial loadings on the rakes.”

AFRISAM IN CAPE N1 UPGRADE TO CUT TRAFFIC CONGESTION

As Cape Town’s highways strain under ever-increasing traffic volumes, AfriSam is working with Cape contractor Martin & East and asphalt giant Much Asphalt to add an extra driving lane to one of the N1’s busiest sections through Bellville.

The project, commissioned by the Western Cape Department of Transport and Public Works in early 2016 and worth R514 million, hopes to make commuting quicker and safer for the 120,000 vehicles that use the route daily.
The contract is one of the largest road projects yet undertaken by Martin & East, according to contracts manager Eitner Truter.

For the 8 kilometres from the Plattekloof Interchange to the R300 interchange, the contractor is surfacing the new lanes mainly with an ultra-thin friction course design (UTFC).
This is being produced by Much Asphalt at its Contermanskloof Plant using a 9 mm and 13 mm cubical roadstone quarried, crushed and screened at AfriSam’s Rheebok Quarry.

This open graded mix allows water to drain off the road more effectively through the interconnected voids between the stones, says Truter, making for better tyre grip, less water spray and lower road noise.

As well as supplying aggregate to Much Asphalt for the road works, AfriSam is also providing Martin & East with readymix for a range of concrete applications.
This includes in-situ median barrier units, 10 retaining structures on the outer edges of the highway, overhead gantry base structures, concrete lined v-drains and the rebuilding of the 60 year old bridge taking traffic over the N1 on Old Oak Road.
The old bridge had to be demolished as the centre piers did not allow for widening of the highway into the median area. Modern highway regulations also required the bridge to be raised by almost a metre.

Traffic intensity on this route presents a number of logistical challenges for the contractor and suppliers, says Truter, who has to coordinate seven construction teams while ensuring that suppliers deliver on time and plant utilisation remains high.

AfriSam territory sales manager Bradley Thomas explains that traffic-related restrictions mean that strict timeframes apply to all deliveries, and makes it especially onerous for readymix supply.

“Our systems must ensure that our trucks arrive punctually and discharge the readymix within the strict time restrictions, despite the traffic,” he says. “There is no room for error, as any delay on our part could delay the entire construction process.”

ENGINEERING OPTIMAL ENERGY SOLUTIONS FOR AFRICA

Zest WEG Group combines its local manufacturing capability with WEG’s range of world class products to engineer energy solutions for customers around Africa, according to the group’s integrated solutions executive, Alastair Gerrard.

Gerrard also emphasises Zest WEG Group’s extensive network of agents and distributors across the continent, who provide vital insights into local conditions, needs and constraints.

“Our solutions are not off-the-shelf, and are tailor made for individual application requirements,” he says. “Our team spends time gaining an in-depth understanding of what the customer really needs, and what the operational constraints are.
In this process, we collaborate with reliable, in-country partners who have local knowledge and experience. This local presence also facilitates quick response times and 24/7 after-sales support.”

Gerrard also emphasises the use of parent company, WEG’s range of motors, variable speed drives and soft starters, as well as its low voltage and medium voltage switchgear.
These products are an integral part of the fit-for-purpose solutions, as is Zest WEG Group’s South African manufacturing capability in terms of generator sets, transformers, substations and other mobile energy solutions.

“Operating a local gen set manufacturing facility staffed by experienced engineers allows us the flexibility to package this offering with an engine and alternator combination to suit the customer preference,” he says.
Zest WEG Group also offers a standard off-the-shelf range of gen sets.

Forming part of Zest WEG Group’s manufacturing operations in South Africa is WEG Transformers Africa which has two facilities capable of producing transformers up to 45 MVA/132 kV and a range of mini substations up to 33 kV.
Also, part of the group is Shaw Controls which is a leading local manufacturer of custom electrical panels, motor control centres (MCCs), containerised electrical solutions and E-houses. He says that E-houses have become popular in Africa as these are pre-assembled and tested in a factory prior to being transported to site by truck.

The focus is on providing integrated solutions in four main areas, says Gerrard, being power generation, electrical infrastructure, mobile energy solutions and group product packages.
Power generation options include diesel, gas, steam, hydro and renewable energy generation solutions, while the electrical infrastructure offering ranges from supply and refurbishment of outdoor and indoor substations to the provision of overhead lines.

Mobile energy solutions, which are engineered to meet specific customer and site needs, are popular in the mining industry but are relevant to any application where operations need flexibility when deploying their electrical systems such as gen sets, substations, skid type solutions or circuit breakers.

COPPER OR ALUMINIUM FOR DRY-TYPE TRANSFORMERS?

While many experts argue the respective pros and cons of using copper or aluminium in dry-type transformers, it is important to understand that innovations in transformer design have ensured that either of these two materials can today be applied with equal effect in most applications, according to David Claassen, managing director of Trafo Power Solutions.

Dry-type transformer specialists Hammond Power Solutions (HPS) – whose products are distributed in Africa by Trafo Power Solutions – has been using both copper and aluminium in the manufacture of conductors and bus bars in its low voltage and medium voltage transformers.

HPS has been a global leader in dry-type transformers for more than a century, and both materials have been used by HPS Europe in its production process for more than forty years.
The company has found no significant difference in the transformer lifespan delivered when using either copper or aluminium; from a technical point of view, the two materials are equivalent.

There is clearly a cost advantage to selecting aluminium as a conductor, as the commodity’s price tends to be significantly less expensive than copper, and more stable over time.
It is therefore not surprising that more than 80% of HPS Europe’s transformer production over the past 40 years – across all markets and applications – incorporates aluminium windings.

However, the argument is sometimes made that aluminium is inferior in terms of conductivity – as it has only 61% of the conductivity of copper – leading to higher energy losses.
Winding temperature is, of course, always a concern, but designers at HPS have been able to maintain temperatures below the insulation rating by designing aluminium winding transformers with conductors with larger cross-sectional areas than those made of copper.

Such design innovations in aluminium conductors have succeeded in reducing their energy losses to the same level as copper. This allows transformers of similar design and with the same temperature rise to exhibit roughly equivalent losses, regardless of the conductor material.

It is also argued that the thermal conductivity of copper is superior to that of aluminium in reducing hot-spot temperature rise in transformer windings. But this is true only when copper and aluminium windings of identical size, geometry and design are compared.

Claassen notes that, in fact, the thermal conductivity characteristics of aluminium can be very close to those of copper, for any given transformer kVA size.
The aluminium coil must just be designed and built 66% larger in its cross-sectional area, for the aluminium coils to achieve the same current-carrying capacity as copper.

HPS designs the cooling surface area, the coil geometry, the air ducting and the conductor shape to produce acceptable hot-spot gradients, regardless of the winding material used.

In terms of aluminium’s lower tensile and yield strength, there have been concerns expressed about its use in cyclic load applications – with aluminium demonstrating only 20% of the rupture stress capacity of copper.
In applications where loads draw high peaks of current, electromagnetic forces can cause movement of conductors and coil leads.

Again, the use of larger sized aluminium conductors addresses this issue, giving the aluminium windings almost the equivalent strength to copper windings.
HPS has found that the ability of its transformers to withstand the long-term mechanical effects of high impact loads or short circuits really depends more on adequate coil balance and lead support than on the choice of conductor material.

Expansion of aluminium due to changing temperatures has caused some problems when bolted connections are improperly installed, as aluminium expands nearly a third more than copper.
With the right type of spring-pressure connection, however, any loosening of joints can be avoided.
This can be done using either cupped or split washers, to provide the necessary elasticity at the joint without compressing the aluminium.
The result is that aluminium joints can perform equally as well as copper joints.

When it comes to connectivity, both copper and aluminium are prone to oxidation and other chemical changes when exposed to the atmosphere.

Cleaning and brushing with a quality joint compound to prevent oxidation is recommended for both materials but is more essential for aluminium.
HPS have a solution for aluminium and copper connectors that involves applying silver or tin-plating to either or both of the conductors in the bolted connection, or by putting a cupal transition plate between the materials.

Claassen emphasises that HPS has developed dry-type transformers for a range of industry applications – from distribution and marine vessels to railway, mining and off-shore rigs.

“Both aluminium and copper have been used in various applications for many years without any problem.
With our innovative design and production procedures, it is possible to avoid the technical limitations of aluminium conductors while retaining the advantages like cost and weight,” he concludes.

INDUSTRIAL, FOOD APPLICATIONS NOW BIG FOR SCREEN SPECIALISTS KWATANI

Known mainly for its large screens and feeders for mining, Kwatani has in recent years expanded substantially into various industrial and food sectors – currently providing screening solutions for almost 50 different materials and products.

According to Warren Mann, Kwatani’s business development manager – industrial division, the company is involved in screening a wide range of materials and foodstuffs from wax beads, carbon and bunker sand to tea, coffee, pet food and rice.

“Our strength is the ability to test the customer’s product or material in our own materials testing laboratory,” says Mann. “This is part of our solution-focused approach to deliver a customised machine that will add optimal value to the customer’s operation.”

These in-house facilities are vital in selecting the correct separator for each application.
By analysing and testing under simulated production conditions it is possible to determine the appropriate machine size and configuration as well as the optimum screen openings.

He highlights that Kwatani has for decades invested heavily in its local design and manufacturing capacity.
In 2012, it also acquired the assets of Lockers Engineers, and continues to supply Lockers customers with the full product range including vibrating screens and feeders, electromagnetic super feeder drives, controllers, vibrating trough conveyors and fluidised bed dryers.

The company’s rectangular R-type separators have a typical application in the sugar industry and are capable of screening 50 to 200 tonnes per hour of sugar to remove lumps and foreign material before grading and packaging.

“Spices and tea processing are other applications where we are actively involved, providing sizing and scalping screens that can handle up to 10 tonnes per hour,” he says.

Food safety comprises a key element in the design and manufacture of the screens that are used in food-related applications, and Kwatani has standardised on using stainless steel.
In addition, its workshop facilities have been optimised accordingly to achieve cost savings in the final assembly.

“We use high-grade stainless steel for any food contact surface, as mild steel tends to rust when exposed to excessive moisture and is not suitable in many food processing applications,” he says. “There are also specific plastics we use that are non-toxic and food-safe, adhering to hygiene and quality standards.
We offer a bonded screen mesh with food-safe epoxy, rather than a bolt down screen mesh, in order to eliminate the risk of bolts coming loose and entering the product stream.”

Kwatani’s S-type round separators are highly versatile and used in many different industries and have a special application in high temperature environments and liquid separation such as removing foreign particles from hot cooking oil.

Industrial products handled by Kwatani screens include the sizing of wax beads that are used in exfoliating creams. Clays such as bentonite and kaolin are also scalped.

“We have screens that can clean the sand in bunkers on golf courses, removing contaminants like grass and soil that have been tramped in by golfers,” says Mann. “In this instance we provide a mobile solution, so the screen can be easily moved to site, and powered by a small generator.”

The range of fine-screen meshes – with apertures of just 38 microns in size – can even separate blood from water and are used in environments like abattoirs.

Kwatani has a low-profile separator option with lower heights than the standard design. This allows it to fit into spaces too small for the standard design where installation space is limited.

Kwatani separators can also be used as safety screens as a last line of defence to remove off-spec product before it is packed.
This reduces the volume of returns and raises satisfaction levels among end-users.

“Manufacturing our own products promotes job creation and skills development, and also gives us the ability to offer high levels of product support, we know the products inside out,” says Mann.