With the South African mining industry being vulnerable to fire breakouts and explosions, local mechanical seals, pumps and complementary pumps product supplier Mechanical Rotating Solutions (MRS) CEO Franscois Steenkamp says fires at mines are reported year in, year out.

He tells Engineering News that fires are often caused by poor ventilation, high temperatures, gas build-up in confined spaces, equipment malfunctions, electrical faults and spontaneous combustions, making fire mitigation at mines crucial.

Steenkamp says there has been an uptick in demand for Straub pipe couplings – particularly for fireproof Straub Fire Fence pipe couplings – driven by greater demand among mines, as well as shipbuilding and offshore companies.

As the couplings provide a solution for firefighting pipework and pipe systems that require increased fire-protection requirements, Steenkamp encourages mines to incorporate the couplings into fire suppression systems that incorporate deluge, water spray, water mist or fire system sprinkler options.

“While misaligned or damaged conveyor belts are often the source of frictional heating, which can lead to fires, some fires – especially at coal mines – are difficult to detect. It is in this instance where your fire suppression system design is of utmost importance,” he notes.

The Straub Fire Fence system – distributed locally by MRS – is based on the standard types of the Straub-Grip and Straub-Flex series, which combine all the advantages of the Straub pipe couplings with fire protection, providing simple, compact, “state-of-the-art” pipe connections while requiring no special tools or pipe-end preparation.

Its innovative progressive sealing effect ensures that when the pressure in the pipe rises, the contact pressure on the sealing lips increases, owing to the flow through the pressure equalisation channel.

The progressive anchoring effect further ensures that when the axial tensile load on the pipe rises, owing to increased internal pressure or external influence, the teeth continuously penetrate deeper into the surface of the pipe to compensate.

Additionally, the Straub Fire Fence system offers improved crush resistance, owing to its being lighter than conventional pipe couplings.

It also incorporates an intumescent plastic that is firmly bonded to the outside of the casting. Under the influence of heat, intumescent materials increase in volume and decrease in density, which produces an isolating heat shield that protects the assembly part.

Hence, in the event of a fire, the intumescent fire-protection coating expands, protectively enclosing the coupling. During this process, the coupling retains its full operational capability without any limitations.

“To minimise the threat of fires in mines, several steps can be taken such as proper training, regular inspections and proper ventilation. “Crucial, however, is the use of fire-resistant materials, in not only the building materials used in mines but also the equipment and machinery,” says Steenkamp.

Services

MRS has been actively marketing the Straub Fire Fence system since 2022, with the company having completed its most recent installation of the couplings for a petrochemical plant in February this year. The couplings were used as part of the design of a passive fire suppression system.

MRS supplies various coal mines, in Mpumalanga, with turnkey pump systems, as well as supplying mines with underground double configuration flameproof pumpsets for the purpose of dewatering shortwall coal mining operations.

MRS pumpsets combine flameproof panels that are incorporated into two single stage suction centrifugal pumps. The centrifugal pumps are made to enclose the parts that could ignite the material being transported or found in the surrounding area.

The flameproof pumps supplied by the company are designed and manufactured to contain explosions and prevent any flames or heat from escaping that could ignite contaminated gases released in the air.

Meanwhile, MRS has also delivered flameproof mobile pumpsets to collieries in Mpumalanga.

“By incorporating flameproof panels and manufacturing mobile trolley units, MRS is able to offer individual mobile pumpsets that are explosion-proof and designed to withstand the most demanding conditions.

“This mobile versatility is increased as every pump model has the capability of easily converting between high-head and high-volume performance, with an easy change of the impeller and wear plate,” concludes Steenkamp.