Published in the August 2007 American Longwall Magazine

Eli Schmader, an engineer for the Pennsylvania manufacturer, said low maintenance, reliability, low noise and absent emissions are the main factors that send mines to batter-operated machines. However, cost is an important factor in the decision, as it is higher, as well as downtime for battery charging - sometimes up to eight hours - unless crews wish to do battery change-outs before shifts.

While the downtime is not a factor for a diesel machine, and no batteries are needed, such units have their own problems. Noise and increased ventilation are big considerations; regulations also require the exhausts of the complex-designed machines are tested every 100 hours, which takes time.

In Brookville's own research and development efforts, Schmader said diesel is being given more attention because of customer feedback. "Customers are asking for diesel units across the board," he said.

"Even though there seems to be more daily maintenance on a diesel machine, it is still more cost effective than the replacement and charging of batteries. If you also take into consideration that in some cases, a battery fleet has to be twice as large as a diesel fleet (run one battery unit while the other is being charged) or an expensive trolley system has to be added and maintained, diesel units are by far the cheaper alternative."

The company continues to market units under both power platforms, with either two-wheel or four-wheel-drive capabilities. Capacities also vary from the 4-5 man jitney-foreman's vehicle to a 14-18 person carrier with a 6 tonne yield locomotive potential.

Most of Brookville's line includes the company's standard construction features, including heavy-duty frames, fire suppression systems, storage compartments and liquid-cooled wet disc brakes. Electric units feature flexible elements such as 30-100HP motors and battery trays that make change-outs easy. All diesel units comply with the newest federal emissions regulations.

Seams all over the nation are getting thinner while emissions regulations are becoming stricter. Schmader said Brookville is staying ahead of the curve on both fronts at the drawing board.

"We are currently designing and building cutting edge low height rail and rubber tired diesel powered machines for the newer low seamed mines coming into production," he said. "The mining trend at this time seems to be pushing for more efficient, cleaner running diesel powered equipment."