Conexpo Achieves Production Goals With Less Downtime And Maintains Product Quality With New Bespoke McLanahan Screen

Conexpo NI Ltd, located in Northern Ireland, has been processing high Polished Stone Value (PSV) aggregates since 1991. Under the joint leadership of Managing Directors Jonny McCluskey and Stephen McCluskey, the company is now one of the premier suppliers to asphalt producers across the south of England, and even into Northern Europe, exporting 1.2 million tonnes per year through the Port of Belfast.

Conexpo focuses on producing and delivering consistent, durable and certified aggregates for the maintenance of some of the most demanding highway infrastructure, where production capacity, timing and product quality are critical.

CHALLENGE

Conexpo’s customers depend on a robust supply to ensure quality aggregates get delivered on time. Highway surfacing projects are expensive, tightly scheduled and often completed during night or weekend road closures, placing immense importance on product consistency, on-time delivery and reliability of supply.

Conexpo owns and operates three high PSV quarry sites, all in close range to the Port of Belfast. The Ballygowan quarry sits on 50 million tonnes of gritstone reserve, an extremely rare sandstone formation known for its durability and high skid resistance. Unlike many aggregates that polish over time, this gritstone continually renews surface texture as traffic wears away the stone, making it highly sought after for road surfacing.

However, the hardness and abrasive nature of this material creates challenges when crushing and screening the mineral to produce finished aggregates.

“Over the last seven years of the plant running, we have experienced a lot of wear-related problems due to the hardness and abrasion of the material,” Jonny McCluskey explained. “This led to downtime and maintenance with the screening equipment,”
Within a few years, the screen producing the final product sizes displayed excessive wear. The increased maintenance demands and unplanned downtime impacted the production volumes of the operation. It became evident that replacing the final screen was essential to maintain an uninterrupted supply of in-spec material to its customers.

Conexpo needed a screen that could withstand the abrasiveness of the gritstone while still achieving the highest standards of quality and production. Conexpo contacted McLanahan to explore a new screening solution that would fit into the existing screening infrastructure at its Ballygowan site.

SOLUTION

Seeking a more suitable and reliable solution, Conexpo partnered with McLanahan to address the persistent screening challenges specifically suited for the abrasive gritstone application.

McLanahan’s engineering team worked closely with Conexpo’s production team to fully understand the site conditions, material properties and performance requirements.

This approach allowed McLanahan to incorporate lessons learned from similar applications while directly addressing operational issues of the previous screen. The new screen was designed to fit precisely where the previous unit had operated.

Within a few days, the McLanahan engineers shared a suitable design solution: a McLanahan 8’x20’ Triple-Deck Horizontal Screen with Production Performance Optimization Drive (ProPOD) Technology. This new, replaceable vibrating drive mechanism is designed for superior performance and service.

The ProPOD Technology simply bolts onto the Horizontal Screen and is joined together by a simple drive shaft. Removal for servicing is quicker and easier than traditional single piece shafts. This design also allows for more clearance between decks.

The ProPOD vibrator mechanism is a compact exciter system designed for quiet, reliable operation and maximum uptime. 

The mechanism offers a wide range of adjustable speed and stroke combinations to suit different screening applications, while oversized bearings deliver enhanced durability and long service life.

The whole screen unit was designed to fit directly into Conexpo’s existing plant layout, replacing the previous unit and significantly minimizing downtime. Installation was carefully planned and efficiently completed within 48 hours.

RESULTS

The McLanahan Horizontal Screen with ProPOD Technology was the perfect solution for eliminating the maintenance and downtime issues Conexpo had experienced with its previous screen, allowing the company to continue to process gritstone and produce high PSV aggregates efficiently.

“We are very pleased with how this machine has been able to replicate our production requirements,” said McCluskey. “With the aggregate that we produce, it’s very important that we maintain product gradings with no variation in the finished product.”

Along with helping achieve a cost-effective solution, the McLanahan team offered Conexpo support throughout all phases of the process.

“We really appreciated the way the communication was continuous through the design, manufacture and installation of the screen,” McCluskey said. “There was a lot of interaction with each other, both by video calls and in person. We were very impressed with the 3-D imagery of the design and the software that was used; we felt we had already seen the screen before it was even manufactured.”

According to McCluskey, the transition to the McLanahan Horizontal Screen has been seamless, delivering reliable performance without compromising the quality aggregates that customers depend on.

“It was a risk to move to another screen manufacturer, knowing our end product might change, but it’s been seamless from start to finish,” McCluskey explained. “The problems that had previously frustrated for so long were considered in the final design.”

By combining Conexpo’s deep understanding of its mineral with McLanahan’s engineering expertise and collaborative approach, the project led to a bespoke screening solution capable of supporting a long-term aggregate supply to help maintain critical highway infrastructure.