In a 24-hour period on April 10 and 11 2014 the Pinnacle Mine longwall produced 35,724 short tons from the Virginia Pocahontas No. 3 Seam, in a seam height of just 56 inches along the 980-foot longwall face.

Pinnacle operates a Cat Gleithobel GH1600 Longwall Plow System.

A previous record was set by this system at Pinnacle in August 2012 when 32,430t were mined in a 24-hour period.

The latest record was set by the same system, mining its second panel after a comprehensive rebuild was performed by Carter Machinery, the Cat Dealer in that area.

The rebuild encompassed a complete rebuild of the headgate and tailgate armoured face conveyor drive, the headgate and tailgate special AFC pans, the stageloader drives and return end, the complete crusher, and all gearboxes for the plow, AFC and stageloader.

Caterpillar global mining sales and support division president Chris Curfman said Carter acquired the rights to sales and aftermarket support associated with the former Bucyrus mining products, both surface and underground, in 2013.

“Supporting and rebuilding a longwall plow system was a new experience for the Carter service team,” he said.

“However, given the record production results attained by the rebuilt system at Pinnacle, it’s obvious that they are up to the challenge of supporting the underground product lines at the same high standards and quality level that they have been delivering for many years on the traditional Cat surface mining products.”

The Cat automated longwall plow system at Pinnacle is the only one operating in the US.

The longwall system has 2 x 800/400 horsepower of installed power for the plow with two operating speeds of 395/197 feet per minute and 2 x 800 horsepower installed power for the AFC.

Each roof support in the system has a total leg cylinder capacity of 715t with an operating height range of 35 to 77.5 inches and is equipped with its own PMC-R electrohydraulic roof support control.

Other units from the Cat Programmable Mining Control family are used for overall face automation and visualisation and also for drive control.

The longwall is equipped with a PF4/1132 face conveyor, a PF4/1542 stageloader and a SB0815 V-belt crusher with a 300 horsepower motor.

To set the new record the cutting depth was calibrated to cut 140mm at a speed of 395 feet per minute when traveling towards the headgate and 250mm traveling at 197 feet per minute to the tailgate.

The depths and speeds are customisable and were selected to optimise loading of the face conveyor.

Caterpillar global mining products division president Tom Bluth said that without the efforts and dedication of the Pinnacle team, this record would not have been possible.

“To safely deliver that kind of output from such a thin seam is remarkable,” he said.