The Century Mine in the Gulf of Carpentaria — the world’s second largest zinc mine — has changed over to steel-bodied Enerpac hydraulic torque wrenches for maintaining its heavy vehicle fleet.
Alloy-bodied hydraulic wrenches weren’t up to the heavy duty task of keeping the 45-strong fleet of Komatsu 830E 240-tonne haul trucks maintained and operational.
“We have about four trucks in our maintenance workshop at any one time, undergoing major overhauls or having breakdowns repaired. We need strong and reliable tools,” said workshop engineer Wesley Lloyd.
“There were dramas with the previous wrenches, which didn’t stand up to the hydraulic pressure required. The tool bodies twisted and leaked oil over our hands. This ultimately could have become potentially dangerous so because of our safety-first priority, we decided to try something different.
“We were already using Enerpac hydraulic cylinders at the mine, so we asked the company to demonstrate their torque wrenches. The results were good. The Enerpac tools can handle the required force.”
Among the haul truck bolting applications performed by the hydraulic wrenches are dismantling and reassembling the front suspension struts, removing and replacing the vehicle nose cones, and servicing the pivot eyes between the rear wheels and the chassis.
The bolt sizes vary, with the 12 bolts on the front suspension struts being 2 inch, and other sizes at the rear.
Century Mine now has three of the versatile W Series of low profile Enerpac hexagonal drive torque wrenches, driven by Enerpac 3000 series air powered pumps.
The W series hexagonal wrenches for low clearance bolting applications weigh from only 1.4-5kg yet have terrific and precisely repeatable torque from 2712-20337 Nm.
They are complemented by the versatile S series of double-acting square drive wrenches, which extends from 2.7-31kg with outputs of 1898-34437 Nm.
“The hydraulic wrenches perform to expectations, with no flexing of the tool body. They sustain their shape, without oil leaks,” Lloyd said.
“The wrenches are no more expensive than the other type we used and there’s also not much weight difference. We thought they would be heavier, being made from steel, but this is not the case, as they aren’t as large.
“The compact tool head means we have more access space in tight spots where it can be hard to get a positive grip on the bolt. This also speeds up the job, since we don’t have so much manipulation to do,” he said.
The Century Mine wrenches are serviced by Enerpac, which offers quick turnaround through Townsville and on-the-ground technical backup from Enerpac Territory Manager Andrew McCall.
Features of the W series torque wrenches include:
• Fast operation from large nut rotation per wrench cycle (30 degree rotation angle) and rapid return stroke. No tools are needed for changing heads.
• Innovative pinless wrench construction incorporating quick release cylinder and automatic crank engagement. Robust design with minimal parts for easy on-site maintenance without special tools.
• Cylinders and low profile heads engineered for ultra-slim compact low clearance tooling with small nose radius.
• Hexagon range 36-115 mm (one and seventeen sixteenth inches to four and five eighths).
In both the hexagonal and square drive wrenches, constant torque output provides high accuracy across the full stroke.
An in-line reaction foot ensures accuracy by reducing internal deflections in the hexagonal drives, while uni-body construction ensures accuracy in the square drives by reducing internal deflections.
The W and S Series of hydraulic wrenches — complemented by Enerpac’s advanced pumping technology and more than 50 years of application expertise — are designed for maximum durability, reliability and safety, with rigid steel design and outstanding power to weight ratios.
The wrenches address the needs of major areas of industry, including mining and energy, infrastructure construction, manufacturing, pipelines, mobile machinery, tracked and heavy vehicles, craneage and fixed plant.