Safer, faster unblocking for crusher at Roadstone quarry

Quarry eliminates risky manual work with WEG-powered crusher unblock system...

In demanding quarrying environments, crushers must withstand heavy loads, abrasive material and harsh outdoor conditions — while always maintaining continuous production. These pressures led Roadstone Ltd., a leading aggregates producer in Ireland, to partner with the motion control specialist Technidrive to modernise its primary jaw crusher system. To achieve this, the companies combined WEG’s drive and motor technology with Technidrive’s innovative control software. The result? A safer, more reliable solution that eliminates hazardous manual unblocking and dramatically reduces downtime.

Quarries are among the most demanding of industrial environments. Machines must process heavy, abrasive material around the clock in dusty, vibration-heavy conditions that place severe strain on equipment. Any unplanned stoppage can grind production to a halt.

This was the dilemma faced at Allen Quarry that is operated by Roadstone and located in Kilmeague, County Kildare, Ireland. Put simply, the quarry faced repeated failures in its primary jaw crusher. When the machine stopped, full of rocks, the resulting blockage meant hours of manual unblocking by site staff. The primary risk was serious injury from working in close proximity to unstable, heavy rock material while manually unblocking the jammed crusher.

To address these issues, Roadstone partnered with Northern Ireland-based motion control specialist Technidrive. Technidrive’s engineers had a solution: an automated crusher unblock system.

An immovable blockage

The quarry’s Nordberg C140 primary jaw crusher is fed directly from blasting, which makes it the first point of entry for material into the plant. When the crusher stopped under load, tonnes of blasted rock could become lodged between the jaws, creating an immovable blockage.

”When the crusher blocked, we had to manually clear it,” explains Tim Cullen, assistant manager at Roadstone. “That meant at least five people with lifting gear, plus hours of dangerous work. Even with strict procedures, you still had hazards like falling rocks, manual handling and working in confined areas.”

Cullen stresses that safety was the primary concern, “Downtime reduction was an added bonus at the end of the project. For us, the main concern was health and safety, we wanted a way of removing those risks completely.”

Roadstone had long been aware of the possibility of a technical solution. In fact, the journey began with a YouTube video.

“We’d actually seen Technidrive’s system in action years ago — our national electrical manager sent me a video back in 2017 or 2018,” explains Tim Cullen. “I saved it, thinking if we ever got the chance to implement it, we would.”

The opportunity to install the system finally came in early 2024, when scheduled maintenance created a window for action. Technidrive supplied a proven, pre-engineered system tailored to Roadstone’s site — a plug-and-play solution built around WEG’s variable speed drive (VSD) and motor technology.

Technology plus expertise

To address Roadstone’s issues, Technidrive supplied its proven crusher unblock system — a solution it had already developed and deployed at other sites. Built around WEG’s CFW11 VSD, the system automates what had previously been hazardous manual work.

“If a jaw crusher stops under load, you’re left with stone wedged between the jaws,” explains David Strain, technical director at Technidrive. “Traditionally, you’d need breakers or winches. Our system uses the WEG CFW11 drive to dynamically accelerate and reverse the motor, rocking the jaw back and forth. By timing these accelerations, it uses the stored energy in the crusher’s counterweights to break through the blockage.”

The software, written by Technidrive, monitors torque, current and bus voltage, ensuring the process is powerful enough to clear blockages but controlled enough to avoid tripping the system. In practice, the procedure takes just a few minutes and is fully automated.

Roadstone received the solution as a pre-assembled panel containing switchgear, the WEG CFW11 drive and local controls. Installation took place during scheduled maintenance in March 2024.

“It was plug-and-play,” said Cullen. “We installed the panel in our switch room, connected the cables, and Technidrive came to the site for commissioning. We integrated it with our SCADA system, so now the operator just presses one button labelled ‘jaw unblock’. Nobody even needs to leave the control room.”

The project also included a major motor upgrade. Roadstone replaced its 200 kilowatt slip ring motor, which required regular brush gear and starter maintenance, with a 200 kilowatt WEG W22 Premium Efficiency squirrel cage motor. The W22 is designed for heavy industry, with features such as reinforced bearings, insulation for vibration resistance and high ingress protection against dust.

“The W22 is ideal for quarry duty. It’s robust enough to handle vibration and dust, and when paired with the WEG drive, it provides higher reliability, efficiency and motor protection,” says Marek Lukaszczyk, WEG UK & Middle East Marketing Manager.

“Beyond that, the combination delivers long-term benefits such as reduced maintenance requirements and a lower total cost of ownership — which are crucial factors in such demanding, around-the-clock environments.”

Transforming safety and productivity

The impact was immediate. A blockage that once took half a day to clear with five people can now be resolved in three minutes by a single operator, without anyone approaching the crusher. Meanwhile, downtime is reduced from up to six hours to just minutes, with safety risks virtually eliminated.

“The difference is incomparable,” said Cullen. “From a health and safety perspective, we’ve eliminated the risk entirely. No one is exposed to falling rocks or confined working conditions. From an operational perspective, we’ve gained hours of production time every time a blockage occurs. It’s a win on every front.”

The solution has proven itself not just in Ireland, but worldwide. Technidrive has delivered crusher unblock systems in Australia, Indonesia and across Europe, working with both end users and original equipment manufacturers.

“Adding this system to any jaw crusher is a no-brainer,” said Strain. “We’ve designed it as an off-the-shelf package that can be installed quickly and supported remotely through our TechniCare platform. For quarries, it transforms both safety and productivity.”

At Roadstone, the collaboration has already sparked further discussions with Technidrive about additional automation projects, including level control for crushers and the replacement of other slip ring motors with modern WEG drive-and-motor combinations.

“Quarrying is a tough industry where downtime is costly and safety is paramount,” concluded Cullen. “This project shows that with the right partners and technology, you can achieve both.”