Pumps refurbishment solutions provider Mechanical Rotating Solutions (MRS) has expanded its premises, in Pretoria, to accommodate a marked influx of refurbishment orders from the mining industry.

“While a new pump has a quick turnaround time for buying and selling, refurbishment orders need workshop space of between one to six weeks. A new workshop, with a receiving bay, sandblasting facilities, tool room, and pumps workshop, as well as various storerooms, was erected,” says MRS CEO Franscois Steenkamp.

The workshop area comprises 1 000 m2 under roof and was completed during December last year. This forms part of a bigger R13-million expansion project which includes storerooms, sandblasting facilities, as well as state-of-the-art office space.

No new technologies are currently being used in the workshop, owing to the amount of refurbishment work that needs to be completed, however, previously outsourced work such as sandblasting and a certain amount of engineering works are now being done in-house to ensure a faster turnaround time and better quality control.

During the first quarter of this year, MRS received a significant increase in refurbishment orders, compared with new installations for its pumps division during the same period for 2018.

Steenkamp notes that strikes, as well as the risks of load-shedding and inconsistent government policy, are negatively impacting on the wider local mining industry; therefore, clients in the mining industry are paying more attention to selecting products that offer greater longevity and benefits, such as energy savings and decreased maintenance costs.

“The process of pumping highly abrasive fluids and solids puts equipment under constant strain. Ultimately, this leads to corrosion and erosion on the main pump components, such as impellers, casings and shafts,” Steenkamp explains.

He adds that engineered polymer coatings, such as MRS’s Belzona product offering, includes a selection of paste-grade materials designed to offer repair solutions for various applications.

The Belzona coating provides a simple and cost-effective way of restoring the original profile and protecting pump components from future damage.

Many pump refurbishments are the result of the substrate having been affected by severe erosion and corrosion. “While replacing the pump seems ideal, maintenance staff are now not only repairing wear and restoring the dimensions of badly eroded areas but also improving on the original design aspects of the pump components.”

Components that have been damaged, such as components on cast-iron and stainless steel pumps, can be rebuilt using Belzona to provide mechanical strength back to the substrate. Once rebuilt, Belzona Supermetalglide is used as a coating on the components of the refurbished pump, resulting in increased pump longevity.

“It is possible to decrease the power consumption of a pump and improve its hydraulic properties by changing the pump surface finish. The smoother the pump walls, the more fluid turbulence will be reduced and, subsequently, the energy required for the pump to transport the fluid through the hydraulic passage,” Steenkamp explains.

Further, Belzona 1341 is a two-part epoxy coating designed to improve pump performance through using hydrophobic technology to repel process fluids and reduce turbulent flow. Efficiency increases of up to 7% have been recorded on new equipment and up to 20% on refurbished equipment.

Pumps can also lose energy, owing to the effects of drag and surface roughness, which are made worse by erosion and corrosion that can, however, be reduced by applying a protective coating to the surface.

“The Belzona range has been formulated to ensure that water simply slides off the pump because of its hydrophobic nature. Abrasion wear is also minimised by Belzona’s blend of lubricant agents and abrasion-resistant fillers,” he maintains.

The Belzona 1341 Supermetalglide ensures that frictional drag is reduced without changing the equipment’s fluid flow characteristics.

Prominent Coal Refurbishment

Steenkamp stresses that the most active mining industry in terms of refurbishments in the first quarter was the coal sector.

Coal mining is particularly strenuous for pumps and their internal components, as coal slurries contain liquid and solid waste. The waste would include several minerals, chemicals, rock particles and dirt that, combined, give slurry highly abrasive, viscous and specific chemical properties.

“Owing to the high wear caused by the particular chemical and physical properties, coal slurries necessitate high-quality and -performance pumps. With a high replacement rate of pumps as a result of this, mining companies are turning to refurbishment instead of replacing the pumps.”

Steenkamp adds that another factor contributing to the increase in the refurbishment of pumps is the general decline in the gold sector. Hampered by a protracted strike in 2018, South African gold production shrank for the eighteenth consecutive month in March this year, with output decreasing by 18% from a year earlier.

Although MRS was quite active in supplying and refurbishing companies in the gold mining sector, this decline has enabled the company to focus on supplying to the coal sector.

Steenkamp maintains that the most significant benefit from the increase in refurbishment orders is the site expansion.

“While the company’s mechanical seals and pipe couplings division has grown enormously over the past ten years, its expertise in pump refurbishment has certainly added a new dimension to augment new pump sales,” he concludes.