Pilot Crushtec says Africa’s only locally manufactured, fully mobile double-roll crusher, the DoppiaTrac DR400, continues to perform well in the field of mobile coal crushing.
The DoppiaTrac DR400 now has a decade of success in the field, according to the company, achieving production rates of 300-400 t/h.
“We designed the DR400 from the ground up to give us the flexibility to produce a truly great crushing solution,” Jorge Abelho, Director, Technical Support at Pilot Crushtec, said. “It has proved itself through its combination of throughput, reliability and economy.”
The machine’s ability to reduce the generation of fines is thanks to the double-roll crusher. While a horizontal shaft impact crusher creates more coal fines due to impact energy, the double-roll crusher forces material through a constant gap, according to the company.
Pilot Crushtec Sales Engineer, Ben Armitage, said: “The crusher uses just enough energy to break the material down to the size of the gap. The DR400 generates less than 5% of 0-6 mm fines, compared to around 12% created by impact crushers – depending on coal hardness and crushing ratios.”
The DR400 boasts a large hopper that is readily fed by loaders or excavators. To increase the average production rate, the unit can be interlocked as part of a crushing train. Connected with a Metso LT106 jaw crusher, the two units can communicate to synchronise the feed rate. This optimises throughput by automatically adjusting the rate of material moving between the machines. The on-board hydraulic rock breaker on the Metso LT106 also allows oversize material to be quickly broken, avoiding blockages and preventing downtime, according to the company.
Crushing efficiency is enhanced by feeding material into the crushing chamber at exactly the same speed that the drums are spinning, Pilot Crushtec explains. This minimises attrition and friction, even at high throughput rates.
Armitage said: “The safety features on the DR400 ensure that it is compliant with demanding safety protocols applied by mining companies. These include full guarding around all moving parts, access points, nip points and crushing points – as well as pull cords and emergency stops to quickly isolate the unit when necessary.”
He explained that the efficient Volvo engine delivers the lowest kW per tonne of any mobile double-roll crusher working in the coal sector. Depending on coal characteristics, the engine’s 160 kW output can convert to a ratio of just 0.4 kW/t.
“The fuel consumption is also a significant factor for operators, and this crusher can run on as little as 17 litres per hour,” Armitage says. “This is achieved with a hydraulic load sensing system and an optimised crusher chamber design, which reduce the power needed to crush the coal.”
The quality and simplicity of the DR400 is demonstrated by the fact that over 25 of these machines are currently in operation around South Africa – one of which exceeds 22,000 hours of operation. Pilot Crushtec says it supports the DR400 through its service levels, stock holding and after-market offerings.