Weba Chutes Systems, a leading local manufacturer of custom engineered chute systems, has secured a contract to supply four chutes to Sibanye-Stillwater's Marikana operation in South Africa. These systems will replace existing conventional chutes that have been underperforming and failing to meet the required standards set by Sibanye-Stillwater.

The four surge bin discharge chutes supplied by Weba Chute Systems will be responsible for feeding UG2 ore with a chrome content of 25% onto a vibrating feeder at the Marikana operation. The vibrating feeder operates at a peak capacity of 250 tons per hour, conveying fines with a maximum lump size of 90 mm and a bulk density of 3.8t/m³.

According to Dewald Tintinger, Technical Manager at Weba Chute Systems, the existing conventional chutes at the concentrator had been causing frequent blockages as well as exhibiting high wear, both of which was unacceptable. "As always when faced with such situations our objective is to custom engineer a chute system that will address these issues and consistently perform according to the required specifications in the long term," he says.

Render from the 3d scan data taken during the site survey showing the current transfer configuration.

These Weba chutes will be manufactured from 6 mm 350 WA mild steel plate, and will incorporate Weba chute quick release lips for enhanced efficiency.

Tintinger says that Weba chutes are renowned for their reliability and durability under the most demanding operational conditions with a typical lifespan of up to 10 years in the field. Many installations have, however, surpassed this lifespan, continuing to deliver optimal performance.

Render from the 3d scan data taken during the site survey showing the relationship between the current equipment on site.

"We continue to receive worldwide recognition for the unique Weba chute concept which is based on the principle of material impacting on surfaces that already contain material, ensuring efficient material flow," he says. "One of the key requirements in transfer chute design is guiding and controlling the material throughout the system and we achieve this by leveraging our cascade or “supertube” concept, which ensures material-to-material contact at all times. Our chutes are engineered to precisely control the direction, flow and velocity of conveyed material, considering factors such as belt width, belt speed, material sizes, shape and throughput.”

By creating this cascade effect, the generation of dust and fine particles during material transfer is significantly minimised leading to a marked reduction in unwanted dust and noise pollution with associated improvements in health and safety.

Showing an engineer in the process of designing a transfer chute.

Achieving the correct and appropriate chute design is crucial, and Tintinger emphasises that the company doesn’t just simply manufacture chutes. “We assess both current and historical data to fully understand the specific requirements and this enables us to identify the critical factors that need to be addressed for a specific application.

“Weba Chute Systems has seen remarkable growth and this further solidifies our position as an international market leader in this field. This statement is also underpinned by the increasing number of retrofit projects we are currently undertaking which indicates that conventional chutes often fail to meet expectations," he says.

Transfer chutes being fabricated at Weba’s workshop in Germiston

Tintinger attributes this to the prevailing belief that chutes are merely platework. Leveraging innovative technology, Weba Chutes Systems established the benchmark for custom engineered transfer points that address the inherent limitations of conventional chute design.

While Weba chutes have primarily been applied in the mining industry for the transfer of materials such as copper, gold, iron ore, diamonds, coal and platinum, the company has noted a growing demand from other sectors including aggregates and sand quarrying, power generation, steelmaking, cement production and food processing.