Once a powerhouse of engineering skills to support the local mining industry, South Africa must now work harder to ensure that it retains and passes on this technical capability – especially in fields like mine winder manufacture and refurbishment.

Parnis Manufacturing works manager Brian Berry says it is a major concern – especially among mining companies and the medium to heavy engineering sector – that there is now a severe lack of skills in certain key engineering fields. In fact, a number of respected engineering companies that serviced the mining and associated industries no longer exist in South Africa.

“Over many decades, South Africa developed a depth of skills in the manufacture, repair and refurbishing of mine winders. In fact, the majority of the winders used on mines on the continent were produced in this country,” says Berry. “Even the design and engineering staff used to come from the workshop floor, so they had an in-depth understanding of what was required.”

With the application of computers to the world of engineering design, this is no longer the case, he notes, adding that this lack of shop floor expertise often needs to be mitigated, so that a supplied design can actually be functionally fabricated.

“The shift away from ‘old-line’ manufacturing and toward more advanced, computer-assisted manufacturing has changed the industry significantly,” he says. “The ongoing incorporation of information technology and automation into our manufacturing processes, for instance, has increased productivity and enhanced quality; but it is still critical that engineering expertise is available.”

He emphasises, however, that the shortage of skills should not be seen just as a problem. It is also an opportunity to leverage the country’s population of skilled artisans to pass on this important knowledge base, so that engineering and manufacturing operations in this discipline can be sustained.

“At Parnis Manufacturing, we regard our depth of experience as a major differentiator, and one which earns us the respect and support of various sectors such as mining and energy,” says Berry. “With our 43 years in business, we are one of the remaining few players providing these solutions, and are using our proud legacy to help ensure the sustainability of this sector and the retention of skills in the country.”

He highlights Parnis Manufacturing’s manufacturing design facility, giving the company the ability to offer skills from concept through to final detailing and manufacture.

“This gives us a huge advantage in our sector, especially as our services are backed up by decades of specialised experience,” he says. “This capability represents a valuable service for the customer, who appreciates its important impact on the quality of the final product.”

Parnis Manufacturing’s extensive 18,000 square metre facility in Tulisa Park, south of Johannesburg, includes over 8,000 square metres of workshop space. The company is able to deploy its enviable skills base through its range of fit-for-purpose fabrication and machining equipment, including vertical boring machines, horizontal boring machines and CNC milling machines, as well as ancillary drilling and welding machinery.

Vertical boring capacity at the facility extends to a table size of 4,5 metres, a turning diameter of 5,3 metres and a turning height of 3,2 metres, with a maximum load of up to 50 tonnes. Its horizontal borers boast a capacity of up to 5,5 metres longitudinal travel by 2,5 metres high.

“Our large vertical boring machine puts us at an advantage to most of our competitors, and allows us to tackle a wide range of engineering projects,” he says. “Other equipment includes milling machines with 4,5 metre longitudinal travel and a 1,8 metres height and an overhead crane lifting capacity of 50 tonnes (tandem).”

The company has decades of experience in manufacturing and refurbishing a range of medium to heavy equipment; a few of these are mine winders and their components, boiler components, fans, fan casings, mill heads and sheave wheels.

A double drum winder being transported to site.


So well regarded is Parnis Manufacturing’s reputation in manufacturing and refurbishing mine winders, that the company recently delivered a 23 tonne, 3 metre single drum winder to a gold mining company in Canada.

The unit will be used as a man winder and service hoist, and will be used to reach a depth of 2,000 metres. Manufacturing the winder using material that is safety critical, Parnis Manufacturing’s contribution was to profile and roll, fabricate and weld, inspect, machine and paint – among other specialist services.

Its quality systems, depth of expertise and range of heavy machinery are among the factors that have ensured its success in this field, according to Brian Berry, works manager at Parnis Manufacturing.

“We work from drawings supplied by our customers, first inspecting the material to ensure that it complies with the specifications, and then preparing it for welding. This is essential to ensure an optimum quality result,” says Berry. “A critical element in the fabrication of the winder drum is our specialised welding and boilermaking skills.”

Boilermakers fabricated the drum using S355J2+N steel, a raw material that can be sourced either from a local supplier or imported – depending on availability and the demands of the project’s timeframe.

“Winder manufacture is certainly a complex engineering task, with the final product comprising a drum, two brake carriers and two brake discs, as well as a shaft, gear box, couplings, bearings and bearing bases,” he says.

After the welding process is completed, the drum goes through full non-destructive testing (NDT) and dimensional inspection to ensure that it conforms to the drawing specifications, and that the requirements of the customer are met. This large component is then sent for stress relieving, after which the gussets and stiffeners are removed and another full NDT and dimensional inspection conducted.

“All this testing is done to ensure the integrity of the material has not been compromised at any stage during the manufacturing process,” says Berry. “The large fabrication is then marked up to ensure machining allowances are within specification, and joint faces are pre-machined on the horizontal boring machines, making use of temporary holes.”

Parnis Manufacturing’s facility is equipped with horizontal borers which have capacities of up to 5,5 metres longitudinal travel and a height of 2,5 metres. The drum is then assembled with temporary fasteners and is inspected once again. Following this process, it is set up for further pre-machining on the drum, leaving material for the final machining phase.

“The drum is then dismantled and final machining of the joint faces – with joint holes – is conducted,” he says. “Final assembly is done followed by final machining using the vertical boring machine.”

Vertical boring capacity at Parnis Manufacturing extends to a table size of 4,5 metres, a turning diameter of 5,3 metres and a turning height of 3,2 metres, with a maximum load of up to 50 tonnes. Other equipment at the company’s facility includes milling machines with 4,5 metre longitudinal travel and a height of 1,8 metres, as well as overhead crane lifting capacity of 50 tonnes (tandem).

“We mark off hole positions for the brake disc carriers, as well as for the positions of the shaft, and then drill and ream for brake and shaft carriers,” he says. “A simultaneous process is carried out for the two brake carriers, after which shot blasting and painting can be done. The components are trial assembled before being packed for shipment.”

Berry highlights the depth of expertise in mine winder fabrication and refurbishment which continues to reside in South Africa, and emphasises the value of close communication with the customers during construction, to ensure that the final quality product is perfectly to specification.

Parnis Manufacturing tackles not only new winders, but also has an established track record for the repair and complete refurbishment of mine winders. Outlining the refurbishment process, he says the work includes stripping down, cleaning and building up of worn areas, as well as extensive machining.

Trunion machining underway at Parnis Manufacturing’s facility in Johannesburg

“This is all done on the strength of comprehensive dimensional reports and in close consultation with customer,” he adds. “The machining of the main winder shaft, for instance, requires the customisation of all the related components in line with new size requirements.”

Items like white metal bearings and seals have to be procured in accordance with the exacting tolerances of the reconditioned shaft. The facility even has capacity to refurbish double drum winders, which comprise clutching equipment, drum bushes, stub shafts and various other components.

“It is important to remember that customers expect the refurbished equipment to function as new, so our artisans and technicians must be at the top of their game to get the most out of our reconditioning facility,” says Berry. “Where possible, we also work closely with original equipment manufacturers to ensure that the right quality procedures are followed to achieve the best quality result.”

Parnis Manufacturing’s engineering capability covers the design, fabrication, machining and manufacture of medium to heavy equipment, which includes crushing equipment, mining skids, e-houses, mills and mill heads.


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.”


An established track record for quality manufacture resulted in Parnis Manufacturing securing a contract to fabricate modular electrical houses (E-House) destined for a mine in Africa.

The continued trend to make use of E-Houses has seen a marked increase in the demand for a company that can manufacture these structures to the necessary quality standards. This is according to Gary Colegate, general manager at Parnis Manufacturing, who says that the latest unit was shipped to the customer at the beginning of the third quarter this year.

Contracts for E-Houses are typically secured by either EPCM contractors or electrical OEM companies, and most have neither the facilities nor the capability to undertake such large fabrication work.

Parnis Manufacturing operates a comprehensively equipped manufacturing plant south of Johannesburg and has the ability to tackle a wide range of engineering projects. Colegate says that most E-Houses comprise a base frame upon which insulated panels are installed to form the basis of the wall and roof structure. The interior is then populated with the requisite electrical equipment and auxiliary systems which include HVAC, fire detection and suppression, furniture and fixtures, and gas systems as well as all cabling reticulation.

“Because E-Houses are custom built for individual customer requirements, it is essential that close communication between all parties is maintained, and this includes the dovetailing of all activities within our facility to ensure that the installation of electrical and other systems can be completed in line with the construction programme,” Colegate says.

The E-Houses in question are intended to serve not only as an electrical control room, but also include office space and toilet.

Established in 1975 by CEO Mario Guerini, Parnis Manufacturing is focused on the fabrication and machining of medium to heavy engineering components for a variety of local industries. It also undertakes container conversions.

The base of the E-house prior to wall assembly.