Industrial solutions provider Mechanical Rotating Solutions (MRS) commissioned an underground double configuration flameproof pump set in August, at a colliery in Mpumalanga, to dewater its shortwall coal mining operations.

The pump set is used to dewater unmined areas at a rate of 60 m3/h, says MRS MD Franscois Steenkamp.

He notes that pumps are often used to transfer hazardous liquids such as flammable, combustible, toxic and corrosive chemicals; thus, certain design and operating practices should be followed.

“With safety being the key concern for all industries, explosion and flameproof pumps are systems specially designed to enclose parts of the pump that could ignite vapours, resulting in an explosion of the transfer media or surrounding atmosphere. The MRS-commissioned pump set combines flameproof panels with two single-stage suction centrifugal pumps.”

These pumps are constructed to enclose the parts that could ignite the material being transported or that are present in the surrounding area. The flameproof pumps are also designed to operate at a lower temperature than similar standard pumps, Steenkamp explains.

“What gives our clients further peace of mind is that, with these units, replacement parts and spares that conform with flameproof specifications are readily available and can be delivered and installed within a very short turnaround time.”

Further, he explains that contaminated air in coal mining or mining in general – referred to as mine damps – is often released during mining operations, including the drilling and blasting stages. Contaminated gases build up in a confined space, as they are unable to disperse, which can lead to explosions.

Therefore, pumps that are not fit for purpose could have disastrous consequences, as a small spark could ignite the contaminated gases.

The company supplies and installs pumps specifically designed and customised for the areas in which they operate; they also adhere to various regulations as prescribed by the mining industry.

To improve the life span, as well as the efficiency of the supplied flameproof pump set, MRS coated the wet end of the pump (the impeller and casing) with Belzona 1341 Supermetalglide.

“This engineered coating is a two-part epoxy coating using hydrophobic technology designed to improve efficiency of pumps, pipes, valves and other fluid handling equipment. Belzona 1341 further protects against erosion and corrosion,” says Steenkamp.

This “high-performance coating” has proven to reduce energy consumption, provide chemical resistance and lower maintenance costs, he adds.

“When offering customers a solution on a flameproof pump, why not also offer them the ability to minimise downtime, extend pump life and produce at a higher efficiency?”

Moreover, Steenkamp explains that it is possible to decrease the power consumption of a pump and improve its hydraulic properties by changing the pump’s surface finish.

“The smoother the pump walls, the more the fluid turbulence will be reduced and, consequently, less energy required for the pump to transport the fluid through the hydraulic passage,” Steenkamp concludes.