Tough machines for a tough industry

In the mining industry, every minute of downtime results in lost income, and one loose fastener can cost a small fortune. This is why Joy Global doesn’t compromise when it comes to bolt security.

At an open-cut mine, virtually no other sound is audible amongst the constant grind of large, heavy-duty machinery smashing, crushing and drilling into solid rock. With minerals buried deep underground, undisturbed for millions of years, it takes a lot of force to extract them. The machines and vehicles on an average mining site are exposed to some of the harshest operating conditions imaginable, including lifting extreme loads and being subjected to constant vibration. As they continue to chip away at the earth’s surface, the whole landscape is radically changed, creating a deep, man-made canyon.

To describe mining as ‘big business’ is a huge understatement. There are whole industries that rely on a steady supply of raw resources. There are entire nations and communities who rely on the mining industry for their livelihoods. In fact, the continued development and industrialisation of human civilisation is based on our ability to dig deep and extract resources from beneath the earth’s surface.

With so much riding on the end product, any hindrance or delay has major consequences, so it’s imperative that everything works smoothly. “Every minute is quantifiable in dollars,” says Nicholas Dame, Senior Engineer at Joy Global Surface Mining. “A one hour delay can cost thousands in lost income, so uptime is extremely important.”

For over 125 years Joy Global’s P&H products have been recognised as amongst the most reliable and productive in the industry. In fact, more than ninety percent of the world’s surface mines use P&H brand equipment. The company’s success is built on its ability to understand the excessive demands of the industry, and build machines that can deliver continuous production. The company prides itself on its fastidious attention to every component, including bolts and nuts. For all their horsepower and ability, even the biggest machines are only one loose bolt away from inaction.

For a number of years, P&H products have used Nord-Lock washers to connect the gearbox to the boom on its electric shovels – an area subjected to heavy vibration. Previously, a fastening solution with a special anti-vibration thread had been used. However, this required a unique tap. When the boom was shipped, it was necessary to fill the tapped holes with lubricant in order to prevent corrosion. Since the assemblers did not have access to the unique tap, they had to use a standard thread tap to remove the corrosion protectant, which also resulted in removal of the thread. When operational, it was not possible to see what type of thread was inside the hole.

“Nord-Lock eliminates this concern completely and allows a quick spot-check to ensure proper installation,” says Nicholas Dame. “It is a proven, low risk solution that gives a good sense of security. It is also less cumbersome and time-consuming. We were using washers anyway, so it was easy to replace it and use a Nord-Lock washer pair instead to eliminate the risk of loosening.”

Joy Global’s latest and largest electric mining shovel – the P&H 4800XPC – is a 135 ton machine. Compared to its predecessor, the 120 ton 4100XPC AC, it can provide up to 20 percent increased productivity with a five percent reduction in cost per ton.

For the P&H 4800XCP, Joy Global decided to make the transition to Nord-Lock X-series. “I see this as the latest version of what is already a very good product,” adds Dame. “It has the same properties with the added benefit of removing relaxation out of the equation.”

In addition to Nord-Lock washers on its gearboxes, Joy Global also use Superbolt tensioners on its crawlers – an area that can be prone to malfunction. “This is another fastener that’s easy to work with,” continues Dame. “Because they’re standard bolts, field assemblers are familiar with them and can fasten them quickly. They’re easily tensioned within minutes.”

With all critical joints secured, P&H machines can do what they do best – maintain production in one of the world’s most important and demanding industries.


About: Leading manufacturer of surface mining equipment with more than 125 years experience in the industry.
Part of: Joy Global Inc.
Founded: 1884

Commercial benefits

  • Proven security – resistant to vibration and significantly reduces risk.
  • Easy to install – does not require tapped holes.
  • Visual – easy to identify whether the bolt has been secured or not.