Modern Mining April 2020

SUPPLY CHAIN News

Specialised dry-type transformers for Saldanha port upgrade December 2019, according to Trafo Power Solutions MD David Claassen. Delivery to site is scheduled for February 2020.

Trafo Power Solutions is supplying dry-type transformers to the Tippler 3 Project at the Saldanha iron ore load-out station. The company is supplying specialised transformers for the Tippler 3 project at the iron ore load-out station. Factory- acceptance testing was completed in

The enclosures are also to be IP33-rated to ensure a high level of ingress protection against moisture and dust. “The enclosure design also incorporates cable boxes and Type C, totally enclosed plug-in bushings for the terminations,” he says. “This provides a boot covering which is touch-potential safe, and also provides for efficient plug-and-play installation.” This is a significant improvement on the regular lug and bolt copper connec- tion, which would just be shrouded by a heat-shrunk material. The special termina- tions also facilitate easier maintenance or removal. “The units will provide the medium- voltage supply for the Tippler 3 project and its associated infrastructure, including equipment like conveyors,” he says. “All the transformers will be supplying non-linear load to a certain extent, so they have been designed with a K-factor of four.” The K-factor is a measure of a transform- er’s ability to withstand the heating effects of non-sinusoidal harmonic currents cre- ated by electronic equipment. The higher the K-factor, the greater the harmonic heat- ing effects.  rolled out on time and on specification to the customer’s satisfaction, says COO Kenny Mayhew-Ridgers. He highlights that on-time delivery of a fit-for-purpose product is as vital as its reliable operation. “The efficiency and quality of our work process allows us to design, manufacture and deliver custom-designed screens in the same timeframes that other OEMs deliver standard models,” says Mayhew-Ridgers. This is particularly demanding as cus- tom-designed equipment undergoes an intensive design process after being veri- fied by rigorous finite element analysis in-house. Prior to dispatch all units endure intensive testing before being commis- sioned on a customer’s site. For this reason, Kwatani boasts its own in-house advanced testing facilities at its Kempton Park facility. Aligned to ISO 9001 standards, the testing protocols have been developed in-house with decades of expe- rience. This allows full testing similar to cold commissioning, even before delivery to site. 

The construction of a third tippler at the Saldanha Bay port is to sustain iron ore export volumes of 60-million tonnes (t) per year when the existing tipplers are refurbished in future. It will integrate with the rail system bringing ore via the 860 km line from mines in the Northern Cape. Key aspects of the new infrastructure comprise the 285-t tippler itself, a loading vault below ground and a conveyor tunnel. New build- ings, service roads, bridges, railway lines, conveyors, lighting and bulk electrical sup- ply infrastructure are also part of Transnet’s upgrade project. Trafo Power Solutions’ contract was for the design, supply and commissioning of five dry-type transformers. There are two 1000 kVA units and a 3 150 kVA unit, both stepping down from 11 kV to 400 V. The other two units are 3 500 kVA and 4 500 kVA capacity respectively, taking 11 kV to 3,3 kV. To resist the corrosive sea air, all the transformer enclosures will be manufac- tured from 3CR12 grade of stainless steel.

Applied voltage test during routine testing, being conducted on the LV windings of the transformer.

Kwatani is supplying four heavy duty vibrat- ing screens and 10 feeders, all engineered for tonnage, to help boost throughput at a Northern Cape manganese mine. According to Kwatani CEO Kim Schoepflin, the large-scale equipment is custom-designed and engineered for tonnage to meet the mine’s challenging operational requirements. Manganese mine ups tonnage with Kwatani vibrating screens “Manganese ore is very demanding on vibrating screens as it has a high specific gravity and is also very abrasive,” says Schoepflin. “Our machines are engineered to perform the application’s duty require- ment while being robust enough to deliver maximum uptime.” The units being supplied include a 3,6 m double-deck scalping screen, a 3 m

double-deck screen, a 2,4 m screen and a 1,8 m dewatering screen. A leading local OEM that has designed and engineered vibrating screens for over four decades, Kwatani has built a reputation for world-class expertise and capability. “Customers choose us for our engi­ neering track record – developing technology that can manage the ton- nages they require,” she says. “This means understanding each mine’s specific conditions, and then building a design to meet a range of complex mechanical and metallurgical factors.” The order to the mine is being

The newly manufactured manganese screen waiting to be transported from Kwatani to the customer.

42  MODERN MINING  April 2020