CONCOR BUILDINGS DOES IT AGAIN AT CONSTRUCTION WORLD BEST PROJECTS

Concor Buildings received industry recognition at Construction World’s 2019 Best Projects awards last night when the company scooped the winning place in the Building Contractors category with its Oxford Parks Phase 1 Project.

In addition to this, the project also received a Special Mention in the AfriSam Innovation Award for Sustainable Construction.

Rui Santos, managing director of Concor Buildings, says that the company has established a reputation for tackling complex projects and delivering these safely, on time and within budget.

The Oxford Parks Phase 1 Project comprises a super basement structure with five buildings of which the BPSA was the first to be completed. Significantly, Concor Buildings has been appointed to continue work on the balance of the structures in the precinct.

About the winning entry
The BPSA head office building, with its compelling triangular shape, is a celebration of inspired architectural design coupled with meticulous attention to detail during construction, creating a strong focus point in Rosebank, Johannesburg.

Constructed by Concor Buildings, the new GBCSA 4-Star Green-rated head office for BPSA is the first completed building in the Oxford Parks Precinct. The Oxford Parks Precinct was selected as a pilot project for the Green Building Council of South Africa to create a green precinct rating tool for public environment projects.

The site of this development is near the Rosebank Gautrain station giving priority to alternative transport systems thus potentially reducing environmental impact of the tenants and customers.

While the architectural team impressed with an iconic design, Concor Buildings’ construction team excelled with innovative solutions for the challenges they faced to deliver a quality structure on time and within budget.

WEBA CHUTE SOLUTION SOLVES BOTTLENECK AT DEPTH

Bottlenecks were preventing one of the world’s deepest gold mines from achieving its targeted throughput on a level 2,850 metres below surface. Weba Chute Systems designed and manufactured the solution.

A short slew conveyor was at the centre of the South African mine’s challenge, providing the only source of ore from that level. Frequent stoppages from belt cuts on this conveyor – often from large rocks stuck in the bottom of the existing chute – meant costly downtime and disrupted material flow to the plant.

The solution, according to, Dewald Tintinger, technical manager at Weba Chute Systems, was to design a completely new chute solution that would remove the need for the slew conveyor arrangement.

“The chute we designed has a bypass leg that drops waste material directly into the bypass, while allowing an inline channel of reef onto the conveyor belt,” Tintinger says. The custom-designed chute was able to replace the mechanical moving component, which also improved the safety of the working area.

The solution – which also involved 70 metres of conveyor belt extension – required the new chute to bifurcate the flow of material from the stopes into a reef stream and a waste stream.

“We achieved that by installing a chute section mounted on a trolley frame, actuated to split the material flow as required,” Tintinger says.

Another benefit was that the area no longer needed regular cleaning. Previously, four shifts of cleaners – comprising four workers each – were required to service the area around the slew conveyor and remove spillage.

Weba Chute Systems technical advisor Alec Bond says the belt on the slew conveyor was also being regularly damaged by the high direct impact of rocks falling from the previous chute.

“Our flow-controlled chute design ensures that the Weba chute has no free-dropping material,” he says. “Instead, the speed of the material is controlled all the way through, right up until the outlet onto the belt.”

The free-falling material was also causing regular damage to the chute itself, requiring frequent liner changeouts. By contrast, the Weba chute requires little maintenance. After a year and a half of operation, the mine has not had to replace any of the parts.

Bond highlights how the underground location of the project added considerably to its complexity. Space at the point of installation was limited, with irregular angles and levels being imposed by the sidewalls and hanging wall. There were also constraints regarding the size of components that could be transported underground, either inside or hanging from the lift cage.

“Every component had to be designed with logistics in mind,” Tintinger says. He highlighted the advantage of Weba’s custom-design capability and ISO 9001:2008 accredited local manufacturing facility, combined with in-house expertise and years of materials handling and transfer point experience.

Installation of the new system had to be conducted with minimal impact on mine operations. It was therefore installed in stages while the plant was operational, according to Tintinger. The shutdown of the plant took place over the Christmas period, as this was the only time available that would not disrupt production.

“This required us to design the chute and associated structures in such a way that we could build it underground while the plant was running,” he says. Construction took place over a six month period alongside the operation of the slew conveyor.

“At the commencement of the Christmas shutdown, the changeover was done and the previous conveyor arrangement removed,” Bond says. “No production was lost during the installation of the new Weba chute and system.”

SLURRYSUCKER HELPS FARMER SAVE WATER

A large Northern Cape farming operation recently moved to drip-irrigation to conserve water. This required cleaner water from its dams – a challenge that Integrated Pump Rental could help to solve.

Using its specialised SlurrySucker desilting solution, Integrated Pump Rental desilted the first of four dams to prove the concept to the customer. Less silt meant not only cleaner water, but higher storage capacity in the dam.

“The customer was so pleased with the result that they have asked us to tackle the other three dams as well,” says Ruaan Venter, rental development manager at Integrated Pump Rental. “Dirty water would have clogged their drip-irrigation pipes and prevented the whole system from working.”

Venter highlighted that this was the first time that the company’s robust SlurrySucker equipment had been used in an agricultural application.

“Our traditional focus is in the mining industry,” he says. “But our experience in removing silt from process ponds on mines was ideal for this work in the agricultural sector.”

In these applications, the SlurrySucker is mounted on a floating barge that is pulled back and forth across a dam. A dewatering pump feeds the surface water down to a dredge-head, which agitates the silt using seven bar of pressure through 16 nozzles. The thick, agitated material is then pumped out of the dam using a fit-for-purpose slurry pump.

One of the key advantages of the system is that it does not damage the clay lining or geomembrane that lines the dam. Previous efforts to desilt these dams had been conducted with tractor-loader-backhoes (TLBs) and this punctured the lining and was unsuccessful.

“We make sure that our agitation heads are operated at a suitable distance from the floor of the dam,” he says. “We also use specially designed hose floats to keep the hoses and electrical cables on the water surface. This avoids any possible damage caused by submerged hoses being dragged across liners.”

There was also vegetation rooted in the silt, which had the potential to clog the suction heads. With its extensive experience and product range, Integrated Pump Rental applied its vortex impeller solution to deal with this.

The efficiency of the SlurrySucker meant quick work. At 80 metres long, 25 metres wide and about two metres deep, a dam could be desilted in just one week. And this is despite a high slurry content of about 60%.

“Using one 37 kW submersible slurry pump on the barge, we were able to pump at about 250 cubic metres an hour through a six-inch pipeline,” says Venter. “This converted to between 50 and 60 dry tonnes an hour.”

He adds that the customer has also entered into a maintenance contract with Integrated Pump Rental to ensure that the dams are regularly desilted for optimal system efficiency.

SASOL AWARD FOR ACTOM TURBO MACHINES

Petrochemical giant Sasol has recognised ACTOM Turbo Machines with one of its top 2019 awards for exceptional service in repair, refurbishment and ongoing maintenance.

The award in the ‘Top Performing Service Supplier’ : Large Enterprises category was recently made by Grace Nndwammbi, Sasol’s senior vice-president supply chain to ACTOM Turbo Machines’ managing director Chris Bezuidenhout at Sasol’s head office in Sandton.

A division of ACTOM (Pty) Ltd, ACTOM Turbo Machines is the only large non-OEM business in its service category to win the award to date. Since its inception six years ago, it has become the largest non-OEM turbo-machinery and high-speed rotating equipment service provider in sub-Saharan Africa.

Sasol is very OEM-reliant in terms of service backup and parts supply, according to Anton Hamman, Sasol’s principal specialist sourcing mechanical equipment. Nonetheless, ACTOM Turbo Machines has proved itself in service provision for turbo machines, where critical and complex skills are required.

“We view turbo machines as the heart of our operations, so it is absolutely essential that the service provider has all the critical skills needed to ensure that the equipment is maintained to OEM specification,” Hamman says. “If you use a non-OEM company for this work, you must be certain they have the required skills and competencies to perform this work to the correct standard every time and understand the associated risks.”

He highlights that safety awareness was a critical aspect of this service. The 36 MW machines in Sasol’s oxygen plant, for instance, are extremely large and heavy. This makes them difficult and potentially dangerous to work on.

“ACTOM Turbo Machines has demonstrated its awareness of the hazards involved and rigorously applies all the procedures necessary to ensure that no one gets injured and that the work gets done as per agreed schedules,” he says “On turbo machines, we look for the best skills in the country and globally, and this is what ACTOM Turbo Machines offers.”

Bezuidenhout says ACTOM Turbo Machines was honoured to have received the award.

“It signifies recognition of the highest order, which we greatly value and cherish,” he says. “It marks an important milestone for us in our ongoing drive to provide the best possible service to industry.”

He commends the company’s maintenance and refurbishment teams on the achievement. ACTOM Turbo Machines has a long-term service agreement with the Sasol group, including Sasol Secunda, Sasol Sasolburg, Sasol Mining and Natref.

The agreement is to provide maintenance on a periodic basis at all these sites. At Sasol Secunda’s oxygen plant, the company has a permanent presence of 40 personnel to attend to all 16 of the plant’s oxygen trains.

SAG MILL TROMMEL SCREEN PROVIDES SIMPLE MECHANISM TO CLASSIFY LARGE VOLUMES OF MILL PRODUCT

The global mining industry has become more discerning about equipment selection for process plant applications, driven by the need to increase throughput and reduce downtime. The SAG mill trommel is one example that delivers on both fronts. With large volume capabilities and a robust and simple structure, it is considered a viable alternative to vibrating screens in SAG mill scalping applications.

Many designers and mill operators believe that the benefits of simplicity and the ability to handle throughputs in excess of 3 500 tons per hour of solids make trommels the preferred equipment for this application.

“A key component ensuring optimal performance of SAG mill trommels is the screen panel, which enables this equipment to classify large volumes of mill product,” says Francois Fouche, senior screening specialist at Multotec.

The company has developed a special range of rubber compounds that are used to manufacture the compression moulded rubber screen panels which are considered the highest wearing items in the trommel.

“We have achieved excellent results from our compression moulded screen panels with wear life extending over six months in 4 500 tons per hour SAG mill applications,” Fouche states.

Multotec has nearly four decades of experience supplying locally manufactured trommel screens and today has the process capability to size SAG mill trommel screens with diameters up to 5.5 metres. The company also designs its trommel screens to suit each customer’s unique requirements and confidently offers process and mechanical guarantees.

“Considering the size and complexity of large SAG mill trommel frames, Multotec is able to apply the latest Finite Element Analysis techniques during the design phase to ensure we reduce fatigue stresses and ensure structural integrity,” Fouche points out.

Given the arduous duty, Multotec covers all frame surfaces that are exposed to the milled product with a wear resistant material, typically rubber.

Fouche says that the operational performance of a SAG mill trommel is another key consideration for Multotec. “As adequate retention time is required for the efficient removal of the fine fraction we need to reduce the high velocity of the slurry that exits SAG mills. We are able to achieve this with various configurations of weir bars. The design of a set of scrolls is an integral part of the design process as these regulate the flow of solids through the trommel screen,” he says.

Multotec has supplied a number of trommel screens for 38 to 40-foot SAG mills that required 500 to 600 mm high weir bars to create sufficient retention time.

Multotec can also supply a range of rubber shell plates and lifter bars to protect the SAG mill trunnion against wear.

“Providing long term customer support is one of the major advantages that Multotec offers,” Fouche says. “Our experienced competent field service crews maintain the screening media and provide condition monitoring on the trommels.”

The Multotec field service maintenance crews can also focus on wear rate indication and monitor the wear resistant lining of the steel structure, and in doing so provide a complete maintenance solution.

SAFETY DURING TOWER CRANE ERECTION CRITICAL

Safely deploying tower cranes on construction sites is critical to raise the pace of the project through higher productivity, however any non-compliance with the numerous safety regulations will have the opposite effect.

Brenden Crous, managing director of local Potain distributor Crane & Hoist Equipment SA, says that the company is well versed in all relevant safety regulations and can take as much of the administrative load as possible off its customers’ shoulders when it comes to lifting-related safety compliance.

“Erecting tower cranes requires competent and experienced crews who undertake the risks associated with this activity. One of our main priorities is to control the risks associated with working at height,” Crous says.

The company covers all bases with the necessary procedures and documentation, so that everything is on hand for inspection. This is very important as Crous highlights that should there be any significant gaps in compliance, then a Department of Labour inspector may consider a site shutdown, leading to costly and inconvenient delays.

“All areas of risk in relation to tower crane safety procedures must be identified, assessed and mitigated so that our customers are not exposed to that risk.”

Crous highlights the importance of the fall protection plan, which must be compiled by a competent person with the necessary training and experience. The plan must address all risks relating to working from a fall-risk position and provide procedures and methods that eliminate the risk of falling.

Tower cranes must comply with both the Driven Machinery regulations and the Construction regulations of the Occupational Health and Safety Act (OHSA). These stringent requirements demand compliance with a range of South African National Standards relating to the installation and maintenance of tower cranes.

Crane & Hoist Equipment SA facilitates these various procedures and permissions by employing qualified lifting machine inspectors, who themselves must be legally and professionally recognised in terms of their scope of expertise and operation.

REGULAR UPGRADES KEEP BENTLEY PARK AT FOREFRONT OF TRAINING

Further enhancements at the Murray & Roberts Training Academy (MRTA) training facility, Bentley Park, are keeping the organisation at the top of its game in mining skills development.

The extensive training infrastructure near Carletonville in Gauteng is constantly adding to its resources as the demand requires, according to Tony Pretorius, education, training and development executive at Murray & Roberts Cementation.

“Among our new facilities is an indexing wall on which drill rig operators can be trained to drill on a horizontal plane,” says Pretorius. “We are also constructing a new tunnel with a face wall on surface to teach miners how to take line and grade and accurately mark off a development end with laser technology.”

He highlights the value of the MRTA’s ‘blended learning’ approach, which makes the learning process more effective by including not just classroom lectures but also e-learning, virtual reality, bench modelling, simulations and integrated learning in a workplace mock-up.

The facility prepares trainees mainly for the hard-rock underground mining environment, in which Murray & Roberts Cementation is a leading contractor.

Other recently developed mock-up facilities at the site include a board-and-pillar layout constructed on surface, to facilitate practical, supervised training for most primary and secondary trackless activities. There is also a figure-of-eight surface roadway for LHD driver training, complete with brake-test slopes. The fleet of trackless vehicles used for training at MRTA includes LHDs, a drill rig, a bolter, a telescopic boom handler, a mechanical scaler and a mechanised shotcreting unit.

“The quality of our skills output – combined with the ongoing demand for entry-level skills by Murray & Roberts Cementation’s mining projects around the country – allow us to turn training into jobs,” he says. “In fact, we are creating hundreds of career opportunities for unemployed youth from communities near our operations.”

With grant-funding from the Mining Qualifications Authority, MRTA will this year train 176 young jobless learners in basic mining-related skills. Those who successfully complete the six-month programme will earn a Level 2 National Certificate in Health, Safety and Environment for Mining and Minerals. Most trainees – of which half are women – are taken up by Murray & Roberts Cementation’s contract mining operations, to begin exciting careers in the mining industry.

PROCESS PLANT OPTIMISATION REALISED WITH FLSMIDTH SMARTCYCLONE™

Process plant optimisation techniques have become a necessity for mines looking to maximise their operating performance by keeping costs low, throughput high and downtime to a minimum. FLSmidth’s automated SmartCyclone™ system is a solution that delivers in all three areas for cyclone circuits, a vital processing element in any plant.

FLSmidth’s SmartCyclone is a monitoring and control solution for reducing cyclone-related process deviations. It also improves cyclone overflow particle size distribution, predicts and controls cyclone maintenance schedules, and optimises closed-circuit grinding processes.

This equates to monitoring the performance of individual cyclones within a circuit in real time, preventing unplanned breakdowns from occurring and monitoring wear rates while ensuring the cyclones are operating optimally at all times. This translates into higher efficiencies in the plant and ultimately, higher profitability.

The SmartCyclone closed circuit grinding optimisation system combines a variety of FLSmidth patented technologies which includes the FLSmidth Krebs SmartCyclone wear detection sensor technology as well as the Krebs’ patented roping sensor technology with patent-pending wireless controller system. This technology immediately identifies if a cyclone is malfunctioning.

The closed circuit grinding optimisation system also incorporates FLSmidth’s ECS/ProcessExpert® process control software with a new patent-pending SmartWear™ cyclone maintenance algorithm. One of the largest benefits associated with this software is the ability to develop a uniform operation strategy that outlines the best way to run the plant. Once this strategy has been established, the necessity to train new operators is reduced.

Reducing or eliminating manual operation, which decreases the potential for human error, is in fact one of the overarching benefits of SmartCyclone.

FLSmidth has more recently enhanced its Krebs SmartCyclone system with wireless technology that
enhances installation simplicity by eliminating the need for individual nodes and the interconnecting cables between the sensors and nodes and associated controllers.

It utilises a central wireless controller that can handle up to 16 sensors per unit; providing real-time wireless detection and communication of roping and/or wear data. The new wireless controller unit is a handheld device that can be removed from its docking/charging station to sync the individual sensors. Once it’s removed, it goes into battery power mode and the user can walk to a desired sensor, activate it with a magnet; trigger and set the necessary operating parameters.

POTAIN TOWER CRANES STILL LEADING WITH TECHNOLOGY THAT WORKS

For decades Potain has built tower cranes that are easy to assembly, flexible in configuration and simply to use, and the Potain MDT 389 topless crane is no different.

The MDT 389 is well suited to crowded construction sites where space is tight and multiple cranes are needed. Like other topless cranes it has been designed to allow more cranes to over swing in a smaller area.

Louw Smit, sales director of Crane & Hoist Equipment SA, the sub-Saharan distributor for Potain tower cranes, says there are a host of features which make the Potain MDT cranes stand out from the competition.

The complete range, including the MDT 249, MDT 259, MDT 269, MDT 319 and the MDT 389, is equipped with Manitowoc’s Crane Control System, or CCS. CCS is a standardised, user-friendly operating system on all Potain tower cranes.

“CCS assists users to enjoy the highest levels of comfort, flexibility, ergonomic control and, most importantly, improved lifting capacity. The enhanced productivity achieved as a result translates into a faster return on investment for Potain crane owners,” Smit says.

In addition to having a fresh and modern design that allows for ultra-fast ground preparation and assembly, the Potain MDT range easily beats the competition when it comes to transportation.

“For example, the turntable, cab mast and Ultra View cab travel in a single compact package, while the counter jib can be folded and the winch platform can be sized to take up less space,” Smit explains. Another advantage is that the mechanisms are grouped in a central technical zone for easier access and maintenance.

As part of its standard features, the Potain MDT 389 is equipped with Manitowoc’s CraneSTAR, a GSM data transfer system that provides information on crane location and operation to support fleet management.

There are two versions of the Potain MDT 389, one with a 12 t maximum capacity and the other with a 16 t maximum capacity. Both versions have up to 75 metre (m) of jib available. The 12 t version can lift 3.4 t at its jib end, while the 16 t version can handle 3.3 t.

Potain also offers a smaller range of CCS equipped cranes, the Potain MDT City line, which includes the MDT 219. Other cranes in the range are the MDT 109, MDT 139 and MDT 189.

Like the Potain MDT 389, the MDT 219 is the highest capacity model in its range. There are two versions of the Potain MDT 219, one with an 8 t maximum capacity and one with a 10 t maximum capacity. All are evolutions of previous Potain MDT City cranes with jib lengths ranging from 55 metres to 65 m and hoisting capacities ranging from 6 t to 10 t.

Smit says the incorporation of CCS into the new range of Potain topless city cranes helps contractors get work done faster and with greater precision. “Aside from the enhanced levels of comfort and ergonomic control, this technology also delivers more precise control in positioning loads as well as increased capacity,” he says.

In fact, for the Potain MDT 219, the inclusion of CCS gives the crane a load chart advantage of up to 12.5% over the MDT 218 A, the equivalent pre-CCS topless city crane from Potain.

These cranes can be engineered to incorporate one of two new crane operator elevator solutions which provide fast and efficient transportation for the operator to and from the cab. Both systems comply with the highest levels of regulation as well.

One of the solutions, CabLIFT, exclusive to Potain cranes, has a slender design allowing it to fit inside all K-mast systems from Potain. It comes in three widths, 1.6 m, 2.0 m and 2.45 m. It is also compatible with all tower crane bases, fixing angles, chassis and cross-shaped bases. CabLIFT’s intelligent design includes a service platform above the main car that provides comfortable access and safety for the erection technicians during the mast assembly process and crane erection.

The other operator elevator solution is TCL, an externally-mounted system.

Potain has long been at the forefront of topless tower crane development, and with the introduction of CCS to its tower cranes, the brand is securing its market leadership position for years to come.

NON-SLIP CHARACTERISTICS OF DIE-LINE ENHANCE WALKWAY SAFETY

Excellent non-slip characteristics is only one of the advantages the Mentis Die-Line range of positive grip pressed section walkway product offers users.

Available in three forms, namely planks, mats and walkways, this locally manufactured walkway pressed section has a positive serration which ensures positive traction in all walking and working surfaces, even where mud, water, grease oil and detergents are present and could cause slippery or hazardous underfoot conditions. The serration on the grating applies irrespective of the direction in which a person is walking.

Lance Quinlan, national technical sales consultant at Andrew Mentis, explains that Die-Line is easy to handle and erect with minimal welding or clipping required. This reduces the need for specialised installation labour.

“Another important advantage that Die-Line offers is its high strength to weight ratio as this ensures an optimum loading bearing capacity and therefore the safety of all who use the walkway system,” Quinlan says.

The Die-Line range also ensures high light penetration for further safety benefits and the sections align perfectly for enhanced aesthetics. The sections are designed for longitudinal span, obviating unnecessary steel support and heavy kick plates, both factors contributing greatly to enhanced cost effectiveness.

Transverse loading is transferred to the integrated kick flats (toe boards) which are provided with two slotted holes at each end and positioned around the neutral axis. Pressed angle splice plates fit on the outside and into the returned top edges, and M10 bolts and nuts are provided for easy installation.

The Die-Line products, together with all the necessary accessories including bolts, washers, nuts, fish plates, jointing channels, saddle clamps, splice plates and mesh clips, can be used for work platforms, catwalks, conveyor walkways, and stair treads.

Die-Line flooring channels are available in three sizes; 150 by 2 400 mm, 250 by 2 400 mm and 305 by 2 400 mm. All are 2 mm thick. Die-Line walkway sections are available either 500 mm or 750 mm wide at a standard length of 2 400 mm and 2.5 mm thick. It can be supplied uncoated, bitumen dipped or galvanised, facilitating use in a wide variety of applications including where harsh chemicals or saltwater is present. Mats are available either 500 mm or 750 mm by 2 400mm long and 2,5 mm thick.

Apart from the obvious safety considerations, Andrew Mentis is able to provide customised solutions for specific customer requirements across a number of market sectors.