For years local citizens of the small town of Cumberland, OH, have been telling people about Big Muskie that resided on the banks of the Muskingum River.
Before you grab your bait and pole, however, you should know that Big Muskie isn’t a fish but rather the world’s largest earthmover.
The giant machine was put out of service after 32 years of service last year.
After 13 years of stripping coal in Meigs Creek, near Cumberland, the Central Ohio Coal Company needed a way to remove more overburden and expose coal faster. As an additional requirement, the machine would have to be able to dig almost 61 meters (200 ft.) into the ground.
In 1965 the Bucyrus-Erie Company of South Milwaukee was called in to help.
As an example of the problems encountered in the design of Big Muskie, consider the stress on a moving boom reaching out over 91.4 meters (300 ft.) from its base.
The primary loads on the dragline boom were simple compared to the complex stresses and strains encountered in the drive shafting and other parts of the machine. The stresses and shock loading induced by the millions of digging, hoisting, swinging and propelling cycles were tremendous.
The hoist rope, suspension and suspended loads on the boom resulted in a compressive force vector down the boom, while swing torque and the slope on which the machine rides resulted in side loads at the boom point.
The boom was filled with an inert gas (nitrogen) to about 690 kPa (100 psi).
Any pressure loss was shown by a lowering of pressure on a gauge. Some fluctuations were due to temperature, but an alarm sounded when pressure dropped below a preset level. A sonic pickup device detected escape.
After two years of planning Bucyrus-Erie finally began construction and two years and 300,000 man-hours later Big Muskie began operation. The final price tag on the project was $25 million.
When completed the machine was 46 meters (151 ft.) in length that is equal to the width of an eight lane highway, weighed a total of 121,500 metric tons (13,500 tons) and a height of 7 meters (22 ft. 6 in.).
The bucket alone weighed 293 metric tons (325 tons) and could hold 17 cubic meters (22 cu. yds.), which could hold 12 cars or 100 members of a high school band.
The machine was capable of digging a pit 56 meters (185 ft.) deep and could dump the overburden two-city blocks away.
Due to its massive size the machine was built in Milwaukee, WI, and shipped to Ohio.
That trip consisted of transporting 33 pieces weighing between 45 and 72 metric tons (50 and 80 tons) in 340 rail carloads and 260 truckloads.
The units were then welded together. The frame, made of 57 parts, revolved on the base atop 128 roller bearings each 55 centimeters (22 in.) in diameter.
To move the machine itself Bucyrus-Erie developed a system that, in effect, gave Big Muskie a pair of oversized 18- by 6- meter (65 by 20 ft.) shoes. The machine rose off the ground via four hydraulic cylinders that were more than 1.8 meters (6 ft.) tall and would move 4 meters (14 ft.) with each step.
Other specifications of Big Muskie include the following:
• Number of drums — 2
• Hoist and drag rope sizes — 12.7 centimeter (5 in.) diameter
• Revolving frame width — 25 meters (83 ft.)
• Rope weight — 46.2 lbs./ft.
• Swing motor size — 932 kilowatts (1,250 hp)
• Number of swing motors — 10
• Hoist motor size — 1,491 kilowatts (2,000 hp)
• Total machine horsepower at peak demand- 46,680 kilowatts (62,600 hp)
• Hydraulic oil capacity — 98,418 liters (26,000 gal.)
During its heyday Big Muskie operated 24 hours a day every day of the week, except for Christmas day, and removed about two and a half million cubic meters (three million cu. yds.) of overburden a month.
Due to the decrease in the demand for high-sulfur Ohio coal in the early 90s, Big Muskie was taken out of service. The retirement was made permanent as the result of the Surface Mining Reclamation Act passed by Congress. The act required that all highwall strip mines be reclaimed and all machines taken off the site of abandoned mines.
In spite of a grass-roots group who tried to keep the machine intact, American Electric Power (AEP), owner of the machine, hired Mayer-Pollock Steel to dismantle Big Muskie.
The company was founded in 1888 and since its inception has been owned and managed by five generations of the Pollock family. The corporate offices are located in Pottstown, PA. The company has an established industry presence within the ferrous and non-ferrous industries serving a variety of steel mills and foundries. In addition its operation includes industrial demolition and dismantling, rigging, hauling and the sale of used equipment.
On May 20 of last year the company used high explosives to cut the 12.7-centimeter (5 in.) cables that held the boom up.
AEP announced the bucket would be maintained as a monument to the men and women who worked the mines of southeastern Ohio. The bucket will become the centerpiece of a display that will tell visitors about the mighty machine, surface mining and reclamation in the area.
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