A full range of approved miniature circuit breakers, offering protection against overload and short circuit in electric conductors, is available from Zest WEG Group.
The WEG MDW and WEG MDWH miniature circuit-breaker line comply with the tripping characteristic curves B and C, according to standards IEC 60898 and IEC 60947-2.
These miniature circuit breakers have been developed to be used in low voltage circuits with direct or alternating current from 2 to 125 A and short circuit breaking capacity up to 10 kA. The full range includes all accessories in both 5 kA and 10 kA, making it possible for the Zest WEG Group to supply customers with complete solutions for specific projects.
All the WEG MDW and WEG MDWH miniature circuit breakers can be used in both commercial and domestic applications.
So complex has modern engine design become that companies wanting to have their engines remanufactured should first look carefully at their service provider’s equipment and in-house skills profile.
According to Andrew Yorke, operations director of Metric Automotive Engineering, the cost benefit of remanufacturing a ‘new generation’ engine is quickly lost if a vehicle starts to underperform as a result of incorrect parts being fitted, or very fine engineering tolerances not being met.
Yorke warned that there are increasingly critical differences between parts that look the same, and that ignorance of these subtleties will lead to sub-optimal engine performance.
“Rebuilders can give our sector a bad name by not closely complying with engine and component numbers, which reflect a range of small size variations even within one manufacturer’s range of products,” he says. “This is vital because it is no longer possible to identify the differences simply by a visual inspection.”
“The danger for the end-user,” he says, “is that it is very difficult to establish why a remanufactured engine is underperforming once the vehicle is back on the road, and the engine’s power, fuel efficiency and emission standards may be compromised.
Achieving a high standard of remanufacture therefore requires both the right workshop infrastructure and a higher level of engineering skill than in the past, he says. When customers source remanufacturing services, therefore, they should audit the remanufacturer’s equipment to check that it is up to the task of being applied to new generation engines.
“As the most comprehensively equipped diesel engine component remanufacturer in the country, our facilities have kept abreast of key industry trends – including the move towards larger and heavier diesel engines,” he says. “So we now have one of the most comprehensive crankshaft grinding facilities in Africa, which is capable of grinding shafts that are up to 4,7 metres long and weigh up to2 tonnes. This allows us to grind crankshafts from industrial compressors right through to the V16 locomotive diesel engine.”
The workshop also boasts a state-of-the-art, three-axis CNC machines – the only two of their kind in Africa. The machines can do line-boring, surfacing and blue-printing of blocks up to 6 metres in length, and are suitable for dealing with the very large engine blocks found in the heavy equipment sector, as well as in marine and rail.
“Tighter machining and clearance tolerances also call for far higher skill levels among remanufacturing engineers and artisans, as there is simply less room for error,” says Yorke. “Our experience in this business ensures that our highly skilled in-house engineers understand new generation engines, and are familiar with all the engine variants and appropriate components. For instance, we just don’t sell parts unless we know the serial number and the arrangement number.”
This capacity and expertise positions Metric Automotive as a world-class remanufacturing centre, he says, whose quality of workmanship is the equivalent of operators anywhere in the world – while offering its services cost effectively to markets across Africa and abroad.
Concor Buildings has secured the contract for the construction of Phase 1 of Oxford Parks. Situated at 199 Oxford Road, the entire Phase 1 and Phase 2 of this prestigious project will comprise four buildings totalling approximately 34,000 m2 and will include the new Johannesburg head office for BPSA.
Being developed by premier property development company Intaprop, Oxford Parks is set to become a vibrant mixed use precinct, comprising upmarket green star rated offices (A & P Grade), apartments and penthouses and hotels, as well as niche supporting retail and cafés.
Rui Santos, managing director of Concor Buildings, says that the current contract includes the construction of three basement levels and BPSA’s six office levels as part of Phase 1.
Work has begun on site, and he says Concor Buildings, formerly Murray & Roberts Buildings, is proud to be associated with this project which has been selected as a pilot project for the Green Building Council of South Africa, to create a green precinct rating tool for public environment projects. Significantly, all buildings within the Oxford Parks Precinct will be designed to a minimum standard of 4 Star Green Rating in terms of the GBCSA standards.
Concor Buildings has an established track record of delivering quality fast track projects, and contractual completion is set for November 2018.
Even as cost cutting eats into maintenance budgets, companies can avoid catastrophic failures if they adopt the structured approach offered by specialists like Marthinusen & Coutts.
Marthinusen & Coutts is a division of ACTOM and according to the division’s projects and engineering services executive, Craig Smorenburg, an effective maintenance programme starts with proper buy-in from the client and their engineering team, as well as from the original equipment manufacturer.
“If all stakeholders understand and support the importance of a structured maintenance programme, then the next step is to agree on the most critical equipment in the client’s facility,” says Smorenburg. “These assets are the ones that must be most closely managed, as they impact directly on the whole operation’s success and sustainability.”
A further study is then conducted to ascertain which elements within each item are critical to maintain, and how the OEM maintenance guidelines must be applied.
“We then develop a strategic level-based maintenance plan, which considers all maintenance requirements and activities,” he says.
“We generally advise clients to conduct their weekly or monthly maintenance activities in-house, otherwise they lose touch with their equipment and lose the necessary skill.”
Marthinusen & Coutts promotes continuous improvement through engaging with its customers. Smorenburg says that this regular interaction between the division and the customer ensures that recommendations are addressed and action plans are realised. A Plan-Do-Check-Act (PDCA) cycle is also followed.
The division has developed its own level based maintenance schedule that incorporates OEM guidelines. This takes the best of each of the OEM requirements to come up with a maintenance schedule that is suitable for all equipment.
He emphasises the skills transfer that occurs when Marthinusen & Coutts technicians are on site with a customer’s maintenance staff.
“We encourage customers to involve their teams in the maintenance activities that we conduct, so they can benefit from transfer of skills from the specialist,” he says. “This gives them hands-on training on how the maintenance should be conducted.”
He says they have applied this approach on a number of sites around Africa, and have noticed a significant improvement in machine condition when they go back to conduct the six month inspections.
Its scientific approach to the design and engineering of transfer chutes has made Germiston-based Weba Chute Systems a leader in its field, saving customers millions in plant efficiencies, longer equipment life and easier maintenance.
“We invest thousands of research hours into understanding the dynamics of bulk materials handling at transfer points,” says Weba Chute Systems managing director Mark Baller. “Employing sophisticated 3D computer software for our system designs, we follow this up with quality manufacture in our ISO 9001:2015 accredited facility. However, this capacity is only as valuable as the data that we get from our customers – so a close working relationship is a vital cornerstone for a successful outcome.”
Baller therefore emphasises that each project begins with a hands-on approach adopted by the engineering team, who together are able to leverage many years of field experience. During a site visit at the start of the process, the team identifies transfer issues and collaborates closely with the customer to develop a tailor-made solution.
“Cost factors are front-of-mind for all stakeholders in the mining sector, so we have to ensure a solution that will increase the return on investment within as short a period as possible,” he says.
It is also insufficient to view the design of transfer chutes in isolation from the broader working environment. Taking a systems approach to bulk solids handling design is essential to ensure operational characteristics are matched throughout the plant. This is a prerequisite to ensuring smooth materials flow through the entire plant.
“Optimising chute performance is a process of defining the geometry of the chute to reliably convey material from one point to another,” he says. “The complexity of chute performance means that chute design should be carried out at the plant design stage, and not added as a conveyance to transfer material from one point to another at a later stage.”
To ensure customer confidence and assurance that the product will meet its stated objectives, Weba Chute Systems provides process and performance guarantees, backed up by its substantial support network. These guarantees, set in accordance with operational and application parameters, are underpinned by quality manufacture, says Baller – a non-negotiable element of all products emanating from the company’s manufacturing facility.
“The results of our research, engineering and quality focus is reduced maintenance requirements in the final product as well as improved transfer conditions, longer conveyor belt life and higher throughput,” he says.
He adds that this philosophy drives the company to constantly improve its products – and to find ever more effective ways of helping clients manage their production costs. The implementation of well-engineered transfer chute systems becomes a key strategy in achieving clients’ budgetary goals
Spartan-based vibrating screen specialist Kwatani, driven by its aggressive cost leadership strategy, is supplying a large exciter-driven grizzly feeder and a sizing screen to the Gamsberg zinc project near Aggeneys in South Africa’s Northern Cape Province.
As the flagship of miner Vedanta Zinc International/Black Mountain Mining, Gamsberg is set to exploit one of the largest known, undeveloped zinc ore bodies in the world, with SA-based ELB Engineering Services conducting the engineering, procurement and construction (EPC) services.
Kwatani was contracted to supply a heavy-duty grizzly feeder capable of feeding over 750 tonnes per hour of ore. Built with cast manganese grizzly bars for durability, this robust unit will withstand maximum lump sizes of up to 1,5 metre in size. Also supplied is a single-deck, motor-driven sizing screen of the same throughput capacity.
“Kwatani has a significant reference base especially in the Northern Cape, where we supply most of the mining vibrating screens,” says Kwatani CEO Kim Schoepflin. “Our installations are particularly well recognised in those areas with arduous applications.”
While price was a key consideration, Schoepflin highlights the customer’s insistence on robust equipment that is fit-for-purpose. Kwatani has been able to meet the project’s tight roll-out schedule, not just with the delivery of equipment but with all the necessary product documentation that will facilitate compliance and safe installation.
“We have completed our part of the project, and are ready to commission the equipment in line with the overall plant construction schedule,” she says. “We also assisted our client with the design of the chute that will feed the grizzly.”
After fabrication, the equipment was fully tested on Kwatani’s in-house test bench at its 17,000 m2 facilities near OR Tambo airport.
The supply of the equipment will come with an extended warranty which will include regular visits by field experts from Kwatani’s fully-fledged branch in the Northern Cape. The capacity of this facility will allow it to conduct both the commissioning of the equipment and the follow-up inspections and interventions.
When economic pressure increases, companies often adopt a cautious stance. Conversely, Countapulse Controls has survived by instituting technological innovation in the face of socio-economic uncertainty.
In its more than 60 years in business, this leading supplier of sensing solutions has created a sustainable business model by focusing on anticipating and exceeding market demands. The resultant range of high quality sensing and monitoring devices has often been first to market.
Since introducing Hengstler mechanical counters to South Africa in the 1950s, the company has witnessed drastic advances in sensing and monitoring technology. Managing directors, Gerry Bryant says that it is critical for companies to keep abreast of ever developing sensing technology.
He emphasises however that all this technology is worth nothing if the technical support is not available. “The sharing of applications knowledge plays a crucial role in increasing productivity and reducing downtime, especially as many companies no longer have internal technical support divisions.”
An aggravating factor for customers is the emergence of a plethora of online shops offering sensing and monitoring technology at bargain basement prices.
“While the low prices might be an attraction, the lack of technical pre- and after-sales advice is a liability. Hi-tech items, by their very nature, require instruction for their maximised performance. It is unlikely that this level of guidance and support is available in an online shopping forum,” Bryant cautions.
In the complex process and manufacturing environments, utilising sensing, monitoring and measuring instruments that have not undergone due diligence and that do not have a great deal of reputational weight is highly risky. The failure of such products causes major production line issues and the safety around such products cannot be guaranteed.
Bryant says that the wise alternative to online shopping is one-on-one technical instruction and support. “A reputable supplier will leverage the years of hands-on experience and expertise resident in its technical staff. OEM training provides the supplier’s team with specialised knowledge and skills pertaining to specific instrumentation. By focusing on tried and tested matching of products to applications, suppliers are able to ensure best fit in all instances.”
Bryant says the company’s hotline is one way of investing its experience and capabilities back into the industry. “This product and applications knowledge is delivered as a value-added benefit to our customers.”
Bryant maintains that when one considers the customer’s application, it is important to understand that selecting sensors is not as simple as matching a model number to a requirement. “One needs to carefully assess the operating environment. Parameters that should be considered include the range of the sensor, the speed of the automatic process, the background conditions and type of product, auxiliary equipment and the circuits within the process. By adopting a structured approach to selecting the most appropriate sensors or flow monitors for a given application, customers will experience enhanced operational advantages.”
Stainless steel tubular handrailing still outranks its competitors, and Andrew Mentis confirms that demand for this product remains consistent.
Corrosion resistant and maintenance free, stainless steel handrailing is the first choice in numerous applications including corrosive and damp environments. “This is because it’s aesthetically pleasing and offers scratch and stain resistant properties making it the obvious alternative to traditional mild steel or painted handrailings,” Lance Quinlan, marketing manager at Andrew Mentis, says.
“Weakened handrailings caused by corrosion and damp can cause accidents as well as raise maintenance costs,” he says. “Mentis’ stainless steel handrailings improve safety and reduce maintenance, and by doing so create a more productive work environment. And more importantly, impact positively on profitability.”
Quinlan says Andrew Mentis produces stainless steel handrailing in three alternative grades: 3CR12, 304 and 316 stainless steel. Stanchions are 45 mm in diameter with a 2 mm wall thickness and base plates designed to allow moisture to drain from the stanchion itself, adding to the corrosion-resistant benefits. The centre hole for the knee rail is drilled and then flared on both sides. The top is also flared and a half round cap is welded into place. The base plate is 8 mm thick and welded to the tube.
The clean modern lines are attractive and the stanchions offer a variety of standard angles and matching accessories. Bends and closures common to mild steel systems are also available for this stainless steel system.
Hand-, knee-rail and bends are manufactured from 31.8 mm diameter tube with a 1.5 mm wall thickness. Bends and closures have swaged ends, improving speed of installation and preventing moisture from penetrating into the joints.
All manufacturing is undertaken with an eye to ease of installation, without the need for special tools. The smooth satin finish combined with the selection of grades offers almost unlimited possibilities for interior and exterior commercial applications.
Heavy engineering and fabrication specialist Parnis Manufacturing has successfully completed a fast track project to supply skids and enclosures for three skid-mounted substations for Schneider Electrics. The large mining skids are bound for Panama.
Parnis Manufacturing project manager Manuel Di Giovanni says by carefully planning ahead during the design stages, and through a close partnership with the customer and other stakeholders, the three medium voltage (MV) transformers could even be delivered ahead of schedule.
The units will be powering machinery such as mining shovels at First Quantum Mineral’s new Cobre Panama copper project, as well as the mine’s primary crushing circuit. The large open pit copper mine will operate in four zones over an expansive area of 13 600 hectares.
“The mining skids allow the units to be moved from one position to another in the open pit, following the movement of the mining machines,” says Di Giovanni.
The company also fabricated the enclosures for each of the mining skids which house the three transformers, which will step down the power from the primary 33.5 KV network to 7.2 KV. The enclosures have a ‘cake lid’ design, being placed over the equipment after it is fitted into the skid.
“This provided a much quicker solution, and was in line with the modular design of the whole project, including the electrical components,” he says.
He emphasises the close collaboration between Schneider Electric and Parnis Manufacturing to provide the best construction solution, alongside the level of flexibility and adaptability that Parnis brings to every project.
“We are known for providing practical solutions from a manufacturing and cost perspective, without sacrificing quality,” says Di Giovanni. “So we are able to assure customers that the product will meet the structural and mechanical specifications as well as the time deadlines.”
He emphasises that Parnis Manufacturing ensures a fit-for-purpose and workable solution by applying its expertise and experience in constructability.
“We do not just manufacture, but rather focus on the solutions that will serve what the client is aiming to achieve,” he says. “We think ahead to anticipate potential issues that could arise, so that these can be addressed in good time without disrupting the project.”
Concor has made a great showing in the 17th annual Construction World Best Projects competition, showcasing excellence in the South African building and civil engineering sectors.
Experienced members of the construction fraternity judge the awards, which are hosted by Crown Publications, the publishers of Construction World magazine. There are six categories available for project entries, and they are judged according to a range of criteria that include construction innovation technology, design, cost, quality, risk management, health, safety, corporate social investment and environmental impact.
In the Building Contractors category, Concor Buildings won the top award for its Menlyn Shopping Centre project; and in the Civil Engineering Contractors category, Concor Infrastructure received a ‘highly commended’ award.
MENLYN SHOPPING CENTRE
Winning the Construction World’s Best Project award in the Building Contractors category is a huge accolade for Concor Buildings, especially given the scale and complexity of this contract. In a R2,2 billion extension and refurbishment, this project has made Menlyn Park Shopping Centre in Pretoria the ‘biggest shopping experience’ in Africa.
The length of the malls – on four levels – is now over 3,4 km, and the shops cover 173 500 m2 of floor space. In addition to all the refurbishment work – which included 14 000 m2 of mall ceilings and tiling – some 60 000 m2 of retail space was added. All this was completed in less than 15 months. There were close to 60 subcontractors on site when the project hit its busiest phase, with about 100 bricklayers placing 3,5 million bricks.
Perhaps the most remarkable aspect of this job was that tenants and shoppers still had access to the existing mall areas so there could be business as usual. This meant that many of the teams worked at night, so that tasks were done before the mall opened each day at 08h00.
The project even received a Green Building 4 Star rating for its environmental and sustainability considerations – a ‘first’ for the retail sector in South Africa.
To fast track the construction programme, the project made use of steel elements which were fabricated in advance in a controlled factory environment. These were used to achieve a contemporary and timeless atmosphere with light-filled spaces, also including aesthetic features.
With limited space, all logistics were carefully planned so that delivered materials could be quickly erected, creating space for the next deliveries. Innovative use was made of smaller cranes and spider cranes on the decks to move steel to required areas.
LOERIESFONTEIN AND KHOBAB WIND FARMS
In the Civil Engineering Contractors category of the Construction World’s Best Projects competition, Concor Infrastructure was highly commended for the two pioneering renewable energy projects in the Hantam Municipality of the Northern Cape: the Loeriesfontein Wind Farm and the Khobab Wind Farm.
In a consortium with CONCO, Concor Infrastructure was responsible for the construction of all 122 wind turbine generator foundations, as well as the adjoining hard stands and internal roads on both sites. Each of the wind turbine bases is 19 metres in diameter, and holds a 99 metre high turbine tower with an 80 tonne nacelle.
Concrete design was key to the performance of this contract, demanding the right strengths while limiting the carbon footprint. The plinths at Loeriesfontein, for example, were constructed using high strength 60 MPa concrete with a design mix of 75% ground granulated corex slag (GGCS) in place of cement. Concor Infrastructure used 50% waste material for both the plinth concrete and the 30 MPa conical base concrete. This helped reduce the project’s estimated overall carbon footprint by 31%.
All this was done in an efficient and continuous work process that allowed each foundation base to be completed from excavation in just 10 days.
In line with Concor Infrastructure’s skills development strategy, these remote projects managed to source and train much of their workforce from the Loeriesfontein community 60 km away.
Situated in such an arid area, the project conserved water through re-use and re-treatment, using a screening system to remove the heaviest solids and bacteriological rollers for the remainder. Many environmental issues were addressed, including protecting and trans locating threatened and endangered plant species, and reclaiming contaminated soil through bioremediation.
Safety was always a high priority, allowing the project to achieve two million Lost Time Incident Free (LTIF) hours in August 2017.
About Construction World’s Best Projects awards
These are the only awards that recognise excellence across the entire built environment from contractors (civils, general builders and specialists) to suppliers to professional services (such as architects and consulting engineers).
The credibility of the awards is ensured by the experience of the three judges, each of whom has been in the industry for decades. They also represent various professional bodies of which they were presidents, namely the Engineering Council of South Africa (ECSA), Consulting Engineers South Africa (CESA), the Chartered Institute of Building (CIOB) and the Master Builders Association (MBA).