Specialist underground mining contractor PYBAR Mining Services has set a new industry best-practice benchmark for removing large diameter reamers safely in an underground environment.
In a safety and cost-efficiency initiative that can be applied globally, PYBAR Mining Servicesutilized an Enerpac SL100 Hydraulic Gantry to provide a safe and efficient way to lift and position the heavy load, where traditional cranes will not fit, and permanent overhead structures are not an option.
Raise bore reamers are used in underground mining worldwide to excavate a circular hole between two levels of a mine, without using explosives. The removal of raise bore reamers has traditionally been a hazardous, complex, costly and time-consuming process.
PYBAR Mining Services Raise Bore and Shaft Lining Manager, Phillip Viljoen, explains that in the raise bore industry, there are two known methods of removing large diameter reamer heads, once the reaming of an underground shaft is complete.
“The first method is to lower the reamer head to the base of the shaft and use a thermal lance to cut the drill string and drag the reamer away from the hole, but this method exposes the worker doing the job to the possibility of falling rocks – a hazard that’s difficult to control,” says Mr Viljoen.
“The second method is to install breast plates in the backs above the reamer head, at the top of the hole, and use air hoists to lift the reamer out of the hole. Steel beams are then placed across the hole, which the reamer is lowered down onto, dragged forward away from the hole, disassembled, and removed. This method is time-consuming, expensive, and complex in the controls required to ensure safe completion of the job,” he said.
“We’ve used the air hoist method before, but due to the costs and complexity of the job we were undertaking, we sought an improved and fit-for-purpose solution, so we worked with Enerpac to develop and safely test the SL100 Reamer Lifting Gantry system, which has become a safety win for the whole raise bore industry.”
Mr Antony Cooper, Enerpac Asia-Pacific Marketing Manager, says “The SL100 Hydraulic Gantry System was key in the success of removing the raise bore reamers in an underground environment. It provided a more efficient way of removing large diameter reamers in an underground environment, and enhanced safety at the same time.”
“The SL100 Hydraulic Gantry is operated remotely, with the Intelli-Lift wireless control system, which is included with all Enerpac hydraulic gantries. The Intelli-Lift controller offers superior safety and control by removing employees from the shaft area during reamer lifts. When the reamer is lifted out of the shaft, the reamer is trammed away from the open shaft, which is then covered with a hole cover to create a safe working area,” said Mr Cooper.
“Essential to the safety and performance of the Enerpac Super Lift gantry range are the skid-tracks it sits on. Skid tracks, available in 3m and 6m sections, are critical to setting up a gantry safely. Skid tracks reduce ground-bearing pressure and ensure the gantries are aligned during travelling,” he said.
Enerpac SL100 Hydraulic Gantries
The cost-effective Enerpac SL-Series Super Lift Gantries provide best-in-class control and high capacity utilising telescopic cylinders offered in 2 or 3 stages. The SL100 Hydraulic Gantry offers higher lifting capacities (up to 110 tonnes) than previously in gantries of this type, while providing accurate load positioning on a compact 610 mm (2 ft) track gauge.
Designed for safe lifting in confined or limited-access spaces, such as underground mining applications, the SL-Series Gantries are easy to mobilise and demobilise. All Enerpac gantries are delivered with job-specific performance properties and control systems to ensure optimum stability and safety.
Innovative and advanced features include:
• Self-contained hydraulics
• Wireless Intelli-Lift controls
• Synchronous lifting and lowering
• Self-propelled wheels or tank rollers with synchronised travel
The lift is controlled by the Enerpac Intelli-Lift wireless control system, which removes the need for workers to be near the shaft area, and instead allows them to be in a safer location during the lift.
The SL100 is designed and tested to meet ASME B30.1-2015 safety standards and is Lloyds witness tested to 125% of maximum working load, to ensure safe, reliable operation.
In addition to comprehensive testing and safety features, the SL100 Gantry is backed in the field by the global Enerpac organisation, which has 50 years’ experience in high pressure (700 bar, 10,150 PSI) hydraulic equipment. Enerpac has a global ‘Goal Zero’ initiative in which they strive for zero safety incidents to occur while using Enerpac tools worldwide.