Published in the December 2005 American Longwall Magazine

Vast mountains of coal dominate the landscape as the Century mine complex comes into view, settled across the Ohio Valley town of Beallsville, about an hour south-west of Wheeling, West Virginia.

American Energy’s Century Mine is one of the operations owned by Murray Energy, which boasts the second largest fleet of longwall mining units in the United States and is the largest private family-owned coal producer in the country.

Step onto the property and two distinct items stand out immediately: every inch of the property is pristine, both above and below ground. Mine management believes that if you can’t manage trash, chances are other manageable items are neglected.

The second factor prominent at Century is the faces you see, as the average age of workers at the operation is an unheard-of 29 years.

Century superintendent and mine manager Ryan Murray said the youth of the operation, which began longwall mining in April 2002, lends itself to this demographic, especially given that the average miner in the United States is 48.9 years of age, according to a recent SME survey.

At the time of construction, the Century Mine was the largest economic development in the state of Ohio for many years. According to a Pennsylvania State University study, 11 jobs in the community are created for every direct mining job at the Century Mine.

Ryan Murray, the son of Murray Energy Corporation founder, chairman and chief executive Robert E Murray, insists their business is blind to the fact that their last name is shared.

In fact, he refers to the elder Murray as “Mr Murray”, saying: “Mr Murray has accomplished a great deal in his 50-year career and, whether or not I am his son, the responsibilities of the job are very real. Our family shares a vision to continue to grow.”

He and the Century staff have an obvious respect for their owner and leader.

Supervisors travel the underground workings in modified golf carts, while the vast majority of employees travel in Goodman man buses and Johnson Industries rides.

Century’s seam height is a comfortable 61in, but entering the area is a different story – the ride of about three miles to the active panel requires a little maneuvering to avoid low areas while riding in the elevated seat of the golf cart.

Murray points out that a renovation of a new track entry is under way, as the original main entry development was built to sustain operations for a much shorter time. Now, with a modified mine plan adopted three years ago, the operation has expanded to more than 27 panels serviced by these mains, among additional reserves which will allow steady production over the next 30 years. What was meant to be somewhat temporary is being renovated to match the strong, stable surroundings of the rest of the mine.

Depth of cover at the mine varies due to topography, but generally ranges between 300ft and 700ft. Strata control is provided by Jennmar in the form of 8ft point anchor bolts, along with supplemental cable bolting and rib bolting as needed; spacing is accomplished in a diamond pattern for cable bolting and 4-by-4 bolt pattern for the 8ft bolts.

Murray said the mine’s geological issues were fairly predictable.

“The immediate roof is comprised of 3ft to 10ft of shaley claystone that grades upwards into 1ft to 3ft of shaley limestone,” he said.

“This is overlain by a massive laminated limestone that typically ranges in thickness between 8ft and 15ft. Cover is moderate and the coal bed is fairly uniform, ranging in thickness between 58 inches and 64 inches over most of the property.”

Murray said pre-mining consisted primarily of core drilling.

“While gate entries are being developed, detailed in-mine mapping is conducted, and for coal quality, channel samples are taken at 500 to 1000ft intervals.”

Three entries are driven for development, using place-change mining with continuous miners. Typical pillar dimensions at Century are 150ft by 78ft, with both 90-degree and 60-degree cross cuts.

In terms of support, cable bolting is used in the tailgate of the gate roads with 9-point cribs. There is occasionally the need for additional supplemental bolting, as well as mesh placement in areas where little to no roof control exists. Wooden headers are also used on an as-needed basis.

Joy 14CM15 and 12CM15 scrubber miners are the machines of choice for the mine’s roadway development. Century also employs 10SC32A shuttle cars, Fletcher Roof Ranger II and DDR roof bolters, 580 scoops by Eimco and DBT (ex-Long-Airdox) 848 Uni-haulers, with one spare per section.

For removal, the operation’s 3000 ton per hour gates are effective in getting product to the 4200tph main line for delivery. Century’s yearly average overall for gate road production is 130ft per shift. The highest recorded average for one full month of production is 181ft per shift, and the mine’s record for a single shift’s production is 315ft.

Century is especially proud of its longwalls – from production to people working the face to the future outlook. The mine recently mined what may arguably be one of the longest panels in the industry at 19,000ft, with panel widths that average 900ft.

When a panel is complete, as it was in October 2005, the longwall changeover process is a fairly rapid 6-8 days. Recovery of all pieces is vital to the move, and according to mine management nothing is ever left behind. Portable Z-drills were used to bolt the face during the moves, said Murray.

The Century longwall face is supported by 181 x two-leg, 500-ton Joy shields, powered by Compac Valve MS31 electrics. The face crew monitors the 59in cutting height by the Joy 7LS1A shearer with 12,470hp/4160V installed power as it takes an average 19,000 clean tons per day from the Pittsburgh seam.

Longwall equipment utilization is 95% on average. Production from the face is carried away at a rate of 2400tph with a Joy face conveyor boasting two 800hp, 4160 volt motors. The AFC belt is 890mm wide and the 42mm chain speeds along at 303ft per minute. Joy’s name plate can also be found on the 1024mm BSL and crusher.

The Century longwall prescribes to a predictive maintenance plan and operates with a service cycle conducted on the longwall every shift. The shift schedule runs with four crews at three shifts per day (48 hours for each worker per week with a six-on, two-off schedule), 359 days per year.

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