The new machine left the SHM plant at Beckley, West Virginia, in early November, with onsite commissioning scheduled for mid-month.

Not only is it the tenth highwall mining unit that the company has sold during 2006, but SHM No.51 is also the first machine to feature a wholly new PLC-based operating and control system.

Based on the Siemens programmable logic control unit, the system offers some major advantages over that previously used on the company’s highwall miners.

As well as the system being more compact, with less hard wiring involved, it offers a new level of internal diagnostics, enabling operators to troubleshoot any problems that may occur faster and more accurately than before.

The graphics-based display also means the system has greater international applicability, allowing simpler access for SHM equipment users worldwide.

The highwall miner to be delivered to Twin State also features SHM’s newly developed right-angle return conveyor, which allows the rear-discharge machine not only to stockpile cut coal sideways on the bench, but brings the coal back to the bench centre. This provides the operator with additional flexibility in terms of stockpiling, especially in narrow-bench applications where “on-the-ground” tonnage capacity may be limited.

Other recently introduced upgrades included on SHM No.51 include the company’s PTM (pushbeam-transfer mechanism) system, which saves time during pushbeam handling on the machine, more powerful traction motors for faster tramming between set-up positions, and linear-position sensors mounted internally within each hydraulic cylinder, offering greater accuracy and protection.

SHM president Steve Antoline said highwall mining in the US continued to contribute to the economy by providing low cost coal.

“SHM is now building on this foundation by focusing on expansion into international markets, bringing coal producers worldwide the benefits of using this unique, proven technology.”